Page 1 Plastic Molding Module (Cat. No. 1771-QDC) Inject Mode...
Page 2 Reproduction of the contents of this copyrighted publication, in whole or in part, without written permission of Allen-Bradley Company, Inc. is prohibited. Throughout this manual we use ATTENTION and Important to alert you to the following:...
Page 3 Summary of Changes Summary of Changes Summary of Changes We revised this publication to include changes due to upgrading the 1771-QDC/B module to a 1771-QDC/C. For These Changes Refer to Page(s) Loss of sensor detection 3 5, 3 10 input range changed back to 0.00 to 10V dc A 3, A 4 Added the section, Record I/O Ranges.
Page 4: Table Of Contents
Table of Contents Summary of Changes ......Use This Preface ....... . Manual Objectives .
Page 5 Table of Contents Jog Your Machine ....... Chapter Objectives ........About Jogging .
Page 6 Table of Contents Determine Word Values for Worksheet 8 B ....8 14 Enter and Download your Worksheet Values ....8 15 Determine and Record Setpoints for Plastication Profile (PPC) .
Page 7: Use This Preface
Preface Use This Preface Manual Objectives Use this preface to familiarize yourself with this manual so you can use it effectively. This manual shows you how to apply the QDC module to your molding machine in the minimum length of time. Since this manual is task oriented, we recommend that you perform these tasks in the following order: Perform this task:...
Page 8: Audience
Audience In order to apply the QDC module to a molding machine, we assume that you are an: injection molding professional experienced programmer with Allen-Bradley PLC-5 processors hydraulics designer or technician Use of Terms We use these abbreviations: Abbreviated Name:...
Page 9 Preface Command Blocks Command blocks provide the parameters that control machine operation. They are transferred from the PLC processor to the QDC module by means of block transfer write (BTW) instructions in software ladder logic. Their abbreviations are: Acronym: Description: Module Configuration Block Jog Configuration Block Injection Configuration Block...
Page 10: Related Publications
Preface Word and bit Numbering The QDC module stores data in command and status blocks. Each word location in a command or status block is identified by an alphanumeric code containing the block acronym and word number. For example, word 09 of the Module Configuration Command Block (MCC) is identified as MCC09.
Page 11 Preface Take time now to familiarize yourself with the Reference Manual, publication 1771-6.5.88. The five sections, in brief, include: summary of each data block used by the QDC module (abbreviated command and status blocks) programming error codes returned by the QDC module for each data block, and recommended procedures to correct these errors detailed listing and explanation of each command word and bit used by, and each status word and bit returned from, the QDC module...
Page 12: Overview Of Inject Mode
Chapter Overview of Inject Mode Chapter Objectives This chapter presents an overview of the 1771-QDC Plastic Molding Module in the Inject mode. We present a summary of Inject features followed by sample applications. Important: This manual assumes you have already read your Plastic Molding Module Application Guide, publication 1771-4.10, and have...
Page 13 Chapter 1 Overview of Inject Mode Figure 1.1 Inject Operation of a Typical Machine Cycle Transition to Injection Pack Hold Pack or Hold Clamp & Eject Operation Post- Plastication Pre- Decompression (Reload) Decompression Injection Phase You can vary the velocity of the ram (screw), or the pressure driving it, so the leading edge of the melt moves through the mold cavity at the desired speed.
Page 14 Chapter 1 Overview of Inject Mode With this Profile You Control Injection With up to 11 Segments Distributed over the Velocity vs. Position Speed Length of the shot Pressure-limited [1] Speed, with a maximum Length of the shot Velocity vs. Position pressure Pressure vs.
Page 15 Chapter 1 Overview of Inject Mode Flash Prevention Example - With a velocity profile (figure 1.4 part 1), the pressure may reach a peak and flash the mold at ram (screw) position segments (part 2) that correspond to events such as: the initial surge (2.a) when the melt front enters a constriction in the mold cavity (2.b) You can remedy this (part 3) by decreasing the ram (screw) velocity at...
Page 16 Chapter 1 Overview of Inject Mode Injection to pack Transition The QDC module ends the injection phase and automatically starts the pack or hold phase when it detects the first of up to four events occurred: Ram (screw) position exceeds a preset limit Ram (screw) pressure exceeds a preset limit Cavity pressure exceeds a preset limit Injection phase elapsed time exceeds a preset limit...
Page 17 Chapter 1 Overview of Inject Mode Example Benefits of Profiling the Pack Phase Molten plastic may cool unevenly in the mold causing variations in density with the end result of warpage and distortion as shown in Figure 1.6. Figure 1.6 Uneven Cooling in Pack Phase Pack Profile Higher density...
Page 18 Chapter 1 Overview of Inject Mode Hold Phase The QDC module controls the hold phase with a pressure vs. time profile. You create the profile based on controlling hydraulic pressure against the ram (screw), or by controlling pressure within the mold cavity resulting from hydraulic pressure against the ram (screw).
Page 19 Post-decompression movement is complete. Screw Speed Beginning with the 1771-QDC/C revision of the module, you can control and monitor screw RPM only when you have configured the QDC module for the singular Inject mode. None of the other mode combinations allow...
Page 20: Install The Qdc Module
Chapter Install the QDC Module Chapter Objectives This chapter guides you through the following installation procedures: record I/O ranges set module jumpers key your I/O chassis install your QDC module wire I/O devices to your QDC module ground your system plan for E-Stops and Machine Interlocks Record I/O Ranges To match your QDC module to your I/O devices, record the I/O ranges of...
Page 21: Set Module Jumper Plugs
Chapter 2 Install the QDC Module Set Module Jumper Plugs Before installing the QDC module, you must select with jumper plugs the I/O ranges that you recorded on Worksheet 2-A. Access and Position the Jumpers Access the jumpers and set them as follows: ATTENTION: To avoid damage to internal circuits, observe handling precautions and rid yourself of any electrostatic charge.
Page 22 Chapter 2 Install the QDC Module Figure 2.1 Jumper Locations on the QDC Module's Circuit Board RIGHT LEFT BOTTOM 10908 I Important: We define jumper plug positions as left, right, top, and bottom. This represents the position of the jumper plug on the 3-pin connector as relative to the sides of the circuit board shown above.
Page 23 Chapter 2 Install the QDC Module Table 2.A Jumper Settings Jumper Function Setting Run/Calibrate (Appendix G) Calibrate = right Run = left [1] I/O Density Standard = top [1] Do not use bottom position Input 1 (Screw position) Input 2 (Screw pressure) Voltage = right [1] Input 3 (Screw RPM) Current = left...
Page 24: Key Your I/O Chassis
Chapter 2 Install the QDC Module Key Your I/O Chassis Use the plastic keying bands, shipped with each I/O chassis, for keying I/O slots to accept only one type of module. This is done to prevent the inadvertent installation of the wrong module into the wrong slot. The QDC module is slotted in two places on the rear edge of the circuit board.
Page 25: Wire The Qdc Module
Chapter 2 Install the QDC Module Failure to remove power from the backplane or wiring arm could cause module damage, degradation of performance, or injury. Place the module in the plastic tracks on the top and bottom of the slot that guides the module into position. Important: Be aware that Pro-Set 600 expects your QDC module to be placed in slot 0 of I/O rack 0 when operating in inject mode.
Page 26 Chapter 2 Install the QDC Module Figure 2.3 I/O Wiring and Grounding Input 1 Screw Customer Position – Sensor Customer – – Input 2 Screw Pressure Sensor To Valve 1 – Output 1 Amplifier Valve 1 Input 3 – – Screw Sensor Output 2...
Page 27 Chapter 2 Install the QDC Module Table 2.B I/O Terminal Designations Transducer I/O Designation Terminal Screw position Input 1 (+) Screw pressure Input 2 (+) Input common Screw RPM Input 3 (+) Cavity pressure Input 4 (+) Valve 1 Output 1 (+) Output common Valve 2 Output 2 (+)
Page 28: Ground And Shield Your I/O Devices
Chapter 2 Install the QDC Module Ground and Shield Analog inputs and outputs are sensitive to electrical noise interference. Your I/O Devices Take care to shield them properly. Guidelines: Use 22-gage (or larger) twisted-pair cable, 100% shielded with drain wire, such as Belden 8761 (or equivalent). For cable distances over 50 ft, use 18-gage cable such as Belden 8760 (or equivalent) Ground the cable shield at one end only;...
Page 29 Class A and B conduit by at least 1 foot where conduit runs must cross, cross them at right angles For additional grounding recommendations, refer to the Allen-Bradley Programmable Controller Wiring and Grounding Guidelines, publication 1770-4.1.
Page 30: Plan For E Stops And Machine Interlocks
The next page shows an illustration of a typical grounded PLC power distribution circuit. For ungrounded systems or for more information on grounding and wiring guidelines, refer to Allen-Bradley publication 1770-4.1, Programmable Controller Wiring and Grounding Guidelines. 2-11...
Page 31 Input Device To minimize EMI generation, you should connect a suppression network: for 120V AC, use Allen-Bradley cat. no. 700-N24; for 220/240V AC, use cat. no. 599-KA04. To minimize EMI generation, you should connect a suppression network: for 120V AC, use Allen-Bradley cat.
Page 32: Configure The Qdc Module's I/O
Chapter Configure the QDC Module's I/O Chapter Objectives Your QDC module needs to know the characteristics of your ram (screw) sensors. In this chapter, we describe how you determine these characteristics and download them to the QDC module. Topics include: signal ranges from pressure, position, and RPM sensors minimum and maximum sensor signals corresponding to minimum and maximum pressures, positions, and RPM...
Page 33 Chapter 3 Worksheet 3 A Select Module Parameters Code: Example: If you select Inject operation with English units: MCC02 = 00000000 00001000 Select I/O Ranges for your Sensors Next, configure the QDC module’s I/O ranges to match the machine sensors and valves. Refer to Worksheet 2-A from chapter 2 which you filled out when setting the QDC module’s jumpers.
Page 34 Chapter 3 Worksheet 3 B Select Input Ranges for your Sensors Code: Example: If you select an input range of 4-20mA for all four inputs, MCC03 = 11111111 10101010. Worksheet 3 C Select Output Ranges for your Valves Code: Example: If you select 0-10 vdc for all four output ranges, MCC04 = 11111111 01010101.
Page 35: Determine Initial Sensor Configuration Values
Chapter 3 Determine Initial To determine initial sensor configuration values, refer to Table 3.A and Sensor configuration Values specifications that accompanied your sensors, valves, and cylinders. Write down applicable values on Worksheet 3-D. Important: You must enter floating-point numbers and percentages as integers, so we recommend that you write them in Worksheet 3-D in the following format: Use an assumed decimal point position that depends on the range value.
Page 36 Chapter 3 Category: If your: Then Use a Value Equal to: Worksheet 3 D Determine Initial Sensor configuration Values Input Line Control Pro Set 600 Value Description Units Word Address...
Page 37: Download Mcc Values To The Qdc Module
Chapter 3 Download MCC Values Use this download procedure now and later in this chapter. The procedure to the QDC Module requires you to complete the following general steps: enter MCC values into the PLC-5 data table download them to the QDC module (PLC-5 processor in run mode) correct any data entry (programming) errors Next we describe the general steps: Enter MCC Values into Your PLC 5 Data Table...
Page 38 Chapter 3 Important: Pro-Set 600 software downloads all command blocks when your PLC-5 processor enters run mode after a valid MCC block is accepted. All programming errors reported in SYS62 (N40:214) are referenced to the MCC block until SYS01-B08 = 1. Correct Any Data entry (Programming) Errors in MCC Upon receipt of the MCC block, the QDC module tests data for data-entry errors, such as a value out of range.
Page 39: Use Set Output Operation To Move The Ram (Screw)
Chapter 3 Use Set Output Operation To finish configuring the QDC module, you actuate the ram (screw) with to Move the Ram (Screw) the QDC module’s set-output operation that applies percentage values to your QDC module’s outputs to move the ram (screw) in a controllable fashion.
Page 40: Complete Your Sensor Configuration
Chapter 3 Actuate the Ram (screw) with Set output Operation Enter values that result in no motion in these DYC words Output: In Data Word: At Pro Set 600 Address: Enable set-output operation by entering a 1 in DYC01-B08 (Pro-Set 600 address B34/392).
Page 41 Chapter 3 Worksheet 3 E Final Sensor configuration Values Input Line Control Pro Set 600 Value Description Units Word Address 3-10...
Page 42 Chapter 3 Determine Values for the Ram (Screw) Position Sensor ATTENTION: Incorrect values entered in DYC09 through DYC12 may result in rapid ram (screw) motion and potential damage to your barrel or seals of your injection cylinder. To complete the configuration for your ram (screw) position sensor, do the following and enter the results on Worksheet 4-E: Important: If your position sensor has zero and span potentiometers for setting the zero reference and linear resolution, do so during this...
Page 43 Chapter 3 Determine Values for the Ram (Screw) Pressure Sensor To complete the configuration for your ram (screw) pressure sensor, enter on Worksheet 4-E minimum and maximum pressures and corresponding signal levels from manufacturer’s specifications in MCC17-20. Most applications require no further spanning. If your application requires greater accuracy, follow the procedure below: Release system pressure to obtain minimum ram (screw) pressure.
Page 44 Chapter 3 You may now download your adjusted values to the QDC module using the MCC download procedure presented earlier in this chapter. Determine Values for the Cavity Pressure Sensor (if used) To complete the configuration for your cavity pressure sensor, enter in Worksheet 4-E minimum and maximum pressures and corresponding signal levels from manufacturer’s specifications in MCC57-60.
Page 45: Select Optional Configurations
Chapter 3 With your programming terminal, read the signal level returned in SYS35 (N40:187) from your RPM sensor. You may wish to span your RPM sensor at this time. Record this signal level on line 12 for MCC54. 10. Release all flow and pressure from your screw motor and allow the screw to return to rest.
Page 46 Chapter 3 ignores all profile commands (except set-outputs and jogs) until you jog the cylinder back through the deadband into the safe zone at either end The deadband guards against sensor noise flickering the SWTL alarms and requires the operator to jog the cylinder a set distance away from the software overtravel.
Page 47 Chapter 3 Set Up Maximum RPM and Pressure Alarms, and Time Delays The QDC module continuously monitors screw RPM, ram (screw) pressure, and cavity pressure inputs. When it detects that the process input equals or exceeds a preset alarm setpoint, the QDC module sets an alarm bit.
Page 48 Chapter 3 Configure a Digital Filter for the Position Input from the Ram (Screw) You may enable an optional digital filter on position inputs to reduce electrical noise from a potentiometer-type position sensor or picked up by your input circuits. To determine if you need a digital filter, move the ram (screw) very slowly.
Page 49: Overview Of Remaining Configuration Procedures
Chapter Overview of Remaining Configuration Procedures Chapter Objectives This chapter introduces you to the remaining procedure necessary to successfully configure your QDC module. You must follow the procedures in the order given. Please use this chapter as a guide. Configuration Concepts The QDC module communicates with your PLC-5 processor through data blocks.
Page 50: Special Command And Status Blocks
Chapter 4 Overview of Remaining Configuration Procedures There are two types of command blocks. They are presented in the following table. Type Which Contain Examples Configuration Blocks Information necessary to configure your Valve spanning module to run a certain portion of a profile information for the injection profile Profile Blocks...
Page 51 Chapter 4 Overview of Remaining Configuration Procedures Overview of Remaining Configuration procedures detailed in the next several chapters are outlined Configuration Procedures below. The procedures are sequential in nature: configuration information determined in initial chapters is needed in later chapters. Step Procedure Information that you enter:...
Page 52: Enter Data Table Values And Download Command Blocks
Chapter 4 Overview of Remaining Configuration Procedures Enter Data Table Values and We refer to these procedures throughout this manual whenever you must: Download Command Blocks enter data table values download command blocks Enter Values into Your PLC 5 Data Table With your programming terminal, enter worksheet values into your PLC-5 data table as follows: Switch the PLC-5 processor to...
Page 53 Chapter 4 Overview of Remaining Configuration Procedures Learn the following procedure because you will use it often. For the block you want to download (subject block), get its ID number from Table 4.A and enter it into DYC61. Table 4.A Information Required to Download a Command Block Subject Pro Set 600...
Page 54 Chapter 4 Overview of Remaining Configuration Procedures Start the download procedure by setting the corresponding download bit (Table 4.A) in your PLC-5 data table. Watch the bit you set in step 3 and wait for Pro-Set 600 software to reset it to zero. This indicates the PLC-5 processor has transferred the block to the QDC module.
Page 55: Jog Your Machine
Chapter Jog Your Machine Chapter Objectives This chapter describes how to: configure all jog block values necessary to jog your ram (screw) test jog values and make changes, if necessary configure values which may indirectly affect clamp and eject jogs About Jogging Jogging your machine is similar to operating it in set-output operation: You apply percentage values to your QDC module’s outputs to obtain the...
Page 56: Determine Initial Jog Values
Chapter 5 Jog Your Machine Determine Initial Jog Values Worksheet 5-A lists all words in which you must enter values to successfully configure your QDC module for jogging the ram (screw). Use it to record: initial values Enter initial values just sufficient to jog in the desired direction. Keep this information in mind: The numbers you enter are %-signal output.
Page 57 Chapter 5 Jog Your Machine Worksheet 5. A Ram (screw) Jog Configuration Values Enter Your Initial Values Here Control Block Pro Set 600 Value Description Units Word Address Inject, Forward Jog JGC17 N40:73 Set Output Values Output #1 % Signal Output JGC18 N40:74 Output #2...
Page 58 Chapter 5 Jog Your Machine ATTENTION: A value of 0 entered in your data table does not necessarily correspond to zero pressure or flow. For an output configured + 10VDC, an output of 50% corresponds to zero volts signal output (see graph). Amplifier electronics or spool offsets may also be designed such that zero volts signal input does not result in no flow or pressure.
Page 59: Write Ladder Logic
Chapter 5 Jog Your Machine Write Ladder Logic Take time now to develop ladder logic (independent of Pro-Set 600 software) to jog the ram (screw) with the QDC module. You need to monitor switches on your operator control panel, and set corresponding command bits.
Page 60 Chapter 5 Jog Your Machine Figure 5.1 Example Jog Programming Rung 6:1 DYC02-B15 | EMERGENCY ********* | STOP EXECUTE | CONDITION ALL STOP EXISTS COMMAND +––––] [–––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––( )–––––+ Rung 6:2 CYCLE | MANUAL |DIRECTION DYC01-B10 CONTROL | SCREW |SOLENOIDS ********** | SELECTOR | FORWARD |ALIGNED TO EXECUTE...
Page 61: Jog Your Ram (Screw)
Chapter 5 Jog Your Machine Jog Your Ram (Screw) Jog your ram (screw) in forward and reverse directions. Experiment with values you entered in the jog configuration block (JGC) until you obtain the desired jog operation. You must download the JGC to the QDC module each time you change a value in the command block to implement the new value.
Page 62 Chapter 5 Jog Your Machine Worksheet 5. B Clamp & Eject Jog Configuration Values for QDC Module in Inject Mode Enter Your Initial Values Here Control Block Pro Set 600 Addr. Value Description Units Word Clamp, Forward Jog JGC33 N40:89 Set Output Values Output #1 % Signal Output JGC34...
Page 63 Chapter 5 Jog Your Machine Write Ladder Logic If your hydraulics require it, take time now to develop ladder logic to Assist with (independent of Pro-Set 600 software) so the QDC module (in inject mode) Clamp & Eject Jogs can assist jogging the clamp and ejector. Otherwise, omit the rest of this chapter.
Page 64: Jog Your Clamp And Ejector
Chapter 5 Jog Your Machine Figure 5.2 Example Programming for Assisting Clamp and/or Ejector Jogs Rung 6:5 CYCLE |DIRECTION DYC01-B12 CONTROL | MANUAL |SOLENOIDS ********** | SELECTOR |CLAMP JOG |ALIGNED TO EXECUTE | (A/S/M) IN| FORWARD |MOVE CLAMP UNASSIGNED | “MANUAL”...
Page 65: Select Command And Status Bits To Sequence
Chapter Select Command and Status Bits to Sequence Machine Operation Chapter Objectives In this chapter, we provide you with tables of command and status bits that you use to write ladder logic to: implement manual functions such as jog, set outputs, and stop step your QDC module through machine cycles We suggest how to assess your logic requirements and based on those requirements how to use bit tables to write your machine’s sequential...
Page 66: Use Command And Status Bit Tables
Chapter 6 Select Command and Status Bits To Sequence Machine Operation Use Command and Status Use the following tables to select command and status bits when writing Bit Tables ladder logic to control manual functions and machine sequencing. Table 6.A Command and Status Bits for Manual Control To Initiate this action Set this bit...
Page 67 Chapter 6 Select Command and Status Bits To Sequence Machine Operation Table 6.C Status and Command Bit Interaction for Automatic Functions For this During execution At completion At completion, if this Profile/Movement this bit in B34 is this bit in B34 is command bit is This status bit is RESET...
Page 68 Chapter 6 Select Command and Status Bits To Sequence Machine Operation Table 6.F Status Bits Category Bit Status Pro Set QDC Block (when = 1) B34/___ Address Jog Status executing screw rotate jog SYS01 B09 executing inject cylinder forward jog SYS01 B10 executing inject cylinder reverse jog SYS01 B11...
Page 69 Chapter 6 Select Command and Status Bits To Sequence Machine Operation Table 6.G Command and Configuration Bits Category Function Enabled Pro Set QDC Block (when = 1) B34/___ Address Non profiled execute set output DYC01 B08 Action Commands execute screw rotate jog DYC01 B09 execute inject cylinder forward jog DYC01 B10...
Page 70: Load Initial Configuration Values
Chapter Load Initial Configuration Values Chapter Objectives This chapter helps you determine, enter, and download configuration setpoints required to tune the QDC module. You will refer to this chapter frequently when tuning the QDC module in chapter 9. We give you information to: assign outputs for control valves select the type of PID algorithm set values for Expert Response Compensation...
Page 71: Use These Worksheets
Chapter 7 Load Initial Configuration Values Use These Worksheets The following table lists command blocks and corresponding worksheets for recording your initial values that you use to configure the QDC module. To configure the QDC module Use this with this configuration block Worksheet Page Injection Configuration Command Block (INC)
Page 72 Chapter 7 Load Initial Configuration Values This page is purposely blank so that the following 2-page worksheets will be on facing pages.
Page 73 Chapter 7 Load Initial Configuration Values Worksheet 7 A Injection Configuration Command Block (INC) Control Word INC01 Bxx Pro Set 600 Addr. B38/bit Value INC Block Identifier Control Word INC02 Bxx Pro Set 600 Addr. B38/bit Value Code: Selected Ram Selected Ram Ram PID Your value...
Page 74 Chapter 7 Load Initial Configuration Values Worksheet 7 A (continued) Injection Configuration Command Block (INC) Enter Your Values Here Control Word Pro Set 600 Addr. Value Description Units INC05 N44:1 1000 Minimum ERC Percentage Velocity Percent INC06 N44:2 1000 Minimum ERC Percentage Pressure Percent INC09 N44:5...
Page 75 Chapter 7 Load Initial Configuration Values Worksheet 7 B Pack Configuration Command Block (PKC) Control Word PKC01 Bxx Pro Set 600 Addr. B38/bit Value PKC Block Identifier Control Word PKC02 Bxx Pro Set 600 Addr. B38/bit Value Selected Ram Selected Cavity Pressure Valve Pressure Valve 000 = Output 1...
Page 76 Chapter 7 Load Initial Configuration Values Worksheet 7 B (continued) Pack Configuration Command Block (PKC) Enter Your Values Here Control Word Pro Set 600 Addr. Value Description Units PKC05 N44:121 1000 Minimum ERC Percentage Cavity Pressure Percent PKC06 N44:122 1000 Minimum ERC Percentage Ram (Screw) Pressure Percent PKC09...
Page 77 Chapter 7 Load Initial Configuration Values Worksheet 7 C Hold Configuration Command Block (HDC) Control Word HDC01 Bxx Pro Set 600 Addr. B38/bit Value HDC Block Identifier Control Word HDC02 Bxx Pro Set 600 Addr. B38/bit Value Selected Ram Selected Cavity Pressure Valve Pressure Valve 000 = Output 1...
Page 78 Chapter 7 Load Initial Configuration Values Worksheet 7 C (continued) Hold Configuration Command Block (HDC) Enter Your Values Here Control Word Pro Set 600 Addr. Value Description Units HDC05 N44:181 1000 Minimum ERC Percentage Cavity Pressure Percent HDC06 N44:182 1000 Minimum ERC Percentage Ram (Screw) Pressure Percent HDC09...
Page 79 Chapter 7 Load Initial Configuration Values Worksheet 7 D Plastication Configuration Block (PLC) Control Word PLC01 Bxx Pro Set 600 Addr. B38/bit Value PLC Block Identifier Control Word PLC02 Bxx Pro Set 600 Addr. B38/bit Value Selected Selected Pressure Valve RPM Valve 000 = Output 1 000 = Output 1...
Page 80 Chapter 7 Load Initial Configuration Values Worksheet 7 D (continued) Plastication Configuration Block (PLC) Enter Your Values Here Control Word Pro Set 600 Addr. Value Description Units PLC05 N44:361 1000 Minimum RPM Control ERC Percentage Percent PLC06 N44:362 1000 Minimum Pressure Control ERC Percentage Percent PLC08 N44:364...
Page 81: Procedure To Determine And Enter Initial Values
Chapter 7 Load Initial Configuration Values Procedure to Determine and Follow this procedure to complete each worksheet: Enter Initial Values Read the text for the subject parameter. Determine your initial value. Important: If you need additional information when determining your initial values, refer to the same configuration blocks in Section 3 of the Plastic Molding Module Reference Manual, publication 1771-6.5.88.
Page 82 Chapter 7 Load Initial Configuration Values Selects: Output #1 Used for RPM Control Output #2 Used for RPM Control Output #3 Used for RPM Control Output #4 Used for RPM Control Record the appropriate bit selections for your valve configurations in the control word of worksheet 7-D.
Page 83: Select The Type Of Pid Algorithm
PID Algorithm When executing pressure or screw RPM versus position or time profiles, the QDC module can use one of two types of PID algorithms: dependent gains (ISA) or independent gains (Allen-Bradley). If B07(B03) = : Then it uses: Dependent Gains (ISA)
Page 84: Set Values For Expert Response Compensatione (Erc)
Chapter 7 Load Initial Configuration Values Important: These recorded PID gain constants and closed-loop tuning procedures in chapter 10 assume the selection of independent (A-B) gains. If, after attempting to tune your pressure loops in chapter 10, you believe you must use dependent (ISA) gain constants, refer to section 3 of the Reference Manual (1771-6.5.88) for information on this option.
Page 85 Chapter 7 Load Initial Configuration Values Table 7.A Set output Setpoints for Unselected Valves If the unselected and the unselected and during profile, and during profile, Then enter valve controls valve type is valve action is you require Pressure Uni directional Direct acting Maximum pressure 9999...
Page 86: Set Your Acceleration/Deceleration Ramp Rates
Chapter 7 Load Initial Configuration Values ATTENTION: A value of 0 entered in your set-output words does not necessarily correspond to zero pressure or flow. If you configured for bi-directional valve operation (–10 to + 10VDC), an output value of 50% gives a zero volts signal output (see graph) while an output value of 0% or 100% gives a maximum signal output .
Page 87: Determine Set Output Values For End Of Profiles
Chapter 7 Load Initial Configuration Values Acceleration Ramp Rates (INC17 20, PKC17 20, HDC17 20, and PLC17 20 The QDC module uses acceleration ramp rates when moving its outputs to a higher setpoint during execution of a profile. They affect both selected and unselected valves.
Page 88: Set Pressure Control Limits
Chapter 7 Load Initial Configuration Values Set Pressure Control Limits Setting pressure control limits lets you span your selected valve outputs for effective control with either direct- or reverse-acting valves. Your machine manufacturer typically provides you with values to configure these limits. Minimum Ram (Screw) Pressure Control Limit (INC41, PKC41, HDC41, and PLC41) The value in this word corresponds to the minimum controllable ram...
Page 89 Chapter 7 Load Initial Configuration Values Selected Ram (Screw) Pressure Valve, Output for Maximum (INC44, PKC44, HDC44, and PLC44) The QDC module uses this word with Maximum Ram (Screw) Pressure Control Limit (word 42) above. Enter the %-signal output that the QDC module uses to drive the selected ram (screw) pressure valve for maximum profile pressure.
Page 90 Chapter 7 Load Initial Configuration Values Selected Cavity Pressure Valve, Output for Minimum (PKC47and HDC47) The QDC module uses this word with Minimum Cavity Pressure Control Limit (word 45) above. Enter the %-signal output that the QDC module uses to drive the selected cavity pressure valve for minimum profile pressure.
Page 91: Set Velocity Control Limits
Chapter 7 Load Initial Configuration Values Set Velocity Control Limits Minimum Velocity Control Limit (INC45) The value in this word corresponds to the minimum controllable ram (screw) velocity during the injection profile. The QDC module uses this word with Selected Velocity Valve, Output for Minimum (INC47) below. The QDC module expects this velocity when setting its selected velocity valve to the percentage output you enter in INC47.
Page 92: Set Rpm Control Limits
Chapter 7 Load Initial Configuration Values Selected Velocity Valve, Output for Maximum (INC48 The QDC module uses this word with Maximum Velocity Control Limit (INC46) above. Enter the %-signal output that the QDC module uses to drive the selected velocity valve for maximum profile velocity. The QDC module expects a velocity equal to INC46 when setting the selected velocity valve to this %-output.
Page 93 Chapter 7 Load Initial Configuration Values Maximum RPM Control Limit (PLC46) The value in this word corresponds to the maximum controllable RPM during the plastication profile. The QDC module uses this word with the Selected RPM Valve, Output for Maximum (word 48) below. The QDC module expects this RPM when setting the selected RPM valve to the percentage output you enter in word 48.
Page 94 Chapter 7 Load Initial Configuration Values Determine Output for Maximum values as follows: 9999 (100%) for uni-directional direct acting valves 0 (0%) or 9999 (100%) for bi-directional valves depending on direction 0 (0%) for uni-directional reverse acting valves If your selected Then the value in word 48 And during the profile, the QDC pressure valve is:...
Page 95: Enter And Download Your Worksheet Values
Chapter 7 Load Initial Configuration Values Watchdog Timer Preset (PLC08) Use the watchdog timer to signal an alarm if the plastication profile takes longer than expected. To inhibit the timer, enter a preset of zero. When the QDC module starts the plastication profile, it: starts the internal timer stops the timer, reports execution time, and resets the accumulated value to zero when it completes profile...
Page 96: Load Initial Profile Values
Chapter Load Initial Profile Values Chapter Objectives This chapter describes how to load setpoints for inject-mode profiles. You determine initial values and enter setpoints into PLC-5 data table for the following profiles: Injection Profile (IPC) Pack/Hold Profile (HPC) Plastication Profile (PPC) Then, you download them to the QDC module.
Page 97: Determine And Record Setpoints For The Injection Profile (Ipc)
Chapter 8 Determine and Record Use Worksheet 8-A to enter setpoints for pressure vs. time and velocity vs. Setpoints position injection profiles. The valve spanning procedures in chapter 9 for the Injection Profile (IPC) require specific values. We have already entered many values for you, and help you determine other values in the text that follows.
Page 98 Chapter 8...
Page 99: Determine Bit Selections For Worksheet 8
Chapter 8 Determine Bit Selections Injection Profile Block Identifier (IPC01) for Worksheet 8 A Bits 07-00 of this word identify it as the first word in a series used to define the injection profile. These bits must be set to 00001001. We recorded these bits on Worksheet 8-A.
Page 100 Chapter 8 Expert Response Compensation (IPC04) -BITS 11, 10, 09, and 08 determine whether you apply Expert Response Compensation (ERC) to injection profiles. ERC is an exclusive algorithm that adjusts for changes in your machine, hydraulics, raw materials, and other process variables. It compensates for abrupt upsets and long term deviations.
Page 101 Chapter 8 Pressure Setpoints (IPC10, 14, 18, 22, 26, 30, 34, 38, 42, 46, and 50) Use these words when configuring pressure vs. position or time profiles. Enter pressure in PSI or Bar. Each pressure setpoint controls the pressure of its corresponding segment. You may use from 1 to 11 segments in your profile.
Page 102 Chapter 8 Time Setpoints (IPC12, 16, 20, 24, 28, 32, 36, 40, 44, and 48) Use these words when configuring pressure vs.time profiles. Enter time in seconds (1 second as 100). Each setpoint controls the time of its own segment. You must use one less time setpoint than pressure setpoints. We recorded 1 second (100) for these time setpoints on Worksheet 8-A.
Page 103 Chapter 8 Transition Setpoints (IPC60, 61, 62, 63, and 64) Use these words when configuring the type of transition from injection to the pack (or hold) profile. The QDC module starts the transition when it detects the first of the following conditions that you enable with a non-zero setpoint.
Page 104: Enter And Download Your Worksheet Values
Chapter 8 -IPC64 determines the position at which the QDC module begins to allow pressure transitions. A non-zero value measured from the mold end forces the QDC module NOT to transition on pressure until the ram (screw) reaches this position. A zero setpoint forces the QDC module to use any non-zero setpoint in IPC62 or IPC63 over the entire injection profile.
Page 105 Chapter 8 Worksheet 8 B Pack/Hold Profile Command Block (HPC) Code: 8-10...
Page 106 Chapter 8 Worksheet 8 B (continued) Pack/Hold Profile Command Block (HPC) Control Word Pro Set 600 Addr. Value Description Units 8-11...
Page 107: Determine Bit Selections For Worksheet 8
Chapter 8 Determine Bit Selections Pack/Hold Profile Block Identifier (HPC01) for Worksheet 8 B Bits 07-00 of this word identify it as the first word in a series used to define the pack/hold profile. These bits must be set to 00001100. We recorded these bits on Worksheet 8-B.
Page 108 Chapter 8 Profile Algorithm (HPC03) The following bits of HPC03 determine whether the pack and/or hold profiles use the ram (screw) or cavity pressure algorithm. -BIT 02 selects the algorithm for the hold profile. -BIT 00 selects the algorithm for the pack profile. 0 = Ram (screw) pressure vs.
Page 109: Determine Word Values For Worksheet 8
Chapter 8 Determine Word Values Cavity Pressure Setpoints (for pack profile: HPC09, 12, 15, 18, and 21) for Worksheet 8 B (for hold profile: HPC26, 29, 32, 35, and 38) Use these words when configuring cavity pressure vs. time pack or hold profiles.
Page 110: Enter And Download Your Worksheet Values
Chapter 8 Profile Offsets (for Pack profile: HPC24 and 25) (for Hold profile: HPC41 and 42) Profile offsets let you shift the amplitude of the entire pack or hold profile up or down, if necessary. You enter these setpoints in PSI or Bar. -HPC24 and 41 determine the offset for cavity pressure profiles.
Page 111: Determine And Record Setpoints For Plastication Profile (Ppc)
Chapter 8 Determine and Record Use Worksheet 8-C to enter setpoints for a backpressure vs. position Setpoints plastication profile. The valve spanning procedures in chapter 9 require for Plastication Profile (PPC) specific values. We have already entered many values for you, and help you determine other values in the text that follows.
Page 112 Chapter 8 Control Word Pro Set 600 Addr. Value Description Units 8-17...
Page 113: Determine Bit Selections For Worksheet 8
Chapter 8 Determine Bit Selections Plastication Profile Block Identifier (PPC01) for Worksheet 8 C Bits 07-00 of this word identify it as the first word in a series used to define the plastication profile. These bits must be set to 00001111. We recorded these bits on Worksheet 8-C.
Page 114: Determine Word Values For Worksheet 8
Chapter 8 Expert Response Compensation (PPC04) -BITS 11, 10, 09, and 08 determine whether you apply Expert Response Compensation (ERC ) to plastication profiles. ERC is an exclusive algorithm that adjusts for changes in your machine, hydraulics, raw materials, and other process variables. It compensates for abrupt upsets and long term deviations.
Page 115 Chapter 8 Backpressure Setpoints (PPC10, 14, 18, 22, 26, 30, 34, 38, 42, 46, and 50) Use these words when configuring backpressure vs. position or time profiles. You enter pressure in PSI or Bar. Each setpoint controls the pressure of its corresponding segment. You may use from 1 to 11 segments in your profile.
Page 116 Chapter 8 The valve spanning procedures in chapter 9 require these initial values. For additional information, refer to the Plastic Molding Module Reference Manual (publication 1771-6.5.88). Time Setpoints (PPC12, 16, 20, 24, 28, 32, 36, 40, 44, and 48) Use these words when configuring either one of the following profiles: backpressure vs time RPM vs time Each setpoint controls the time (in seconds) of its corresponding segment.
Page 117: Enter And Download Your Worksheet Values
Chapter 8 The valve spanning procedures in chapter 9 require these initial values. Where required, we help you select correct final values required by your application in chapter 10. For additional information, refer to the Plastic Molding Module Reference Manual (publication 1771-6.5.88). Enter and Download your After you determine initial values and record them on Worksheet 8-C, you Worksheet Values...
Page 118: Span Your Valves
Chapter Span Your Valves Chapter Objectives This chapter describes how to span your valves using direct-output operation, and verify by running simple open-loop profiles. ATTENTION: Before proceeding, be sure you completed all previous chapters. Failure to do so could result in unpredictable machine motion, with possible equipment damage and/or injury.
Page 119 Chapter 9 Span Your Valves Span Your Injection We recommend that you first span your injection pressure valve for Pressure Valve optimum pressure performance. You do this in four parts: Confirm critical values Span your injection pressure valves Test valve linearity with a pressure vs. time injection profile Set profile pressure alarms Important: You may omit the subsection Span Your Injection Pressure Valve below if you have information from molding machine OEMs or...
Page 120: Span Your Injection Pressure Valve
Chapter 9 Span Your Valves Span Your Injection Pressure Valve Span your injection valve for smooth operation at the highest desired injection pressure. Do this in the following procedure by finding the optimum values for these words: Minimum Pressure Control Limit INC41 (N44:37) Maximum Pressure Control Limit INC42 (N44:38) Selected Pressure Valve, Output for Minimum INC43 (N44:39) Selected Pressure Valve, Output for Maximum INC44 (N44:40)
Page 121 Chapter 9 Span Your Valves Enable set-output by changing DYC01-B08 (B34/392) from 0 to 1. This forces the QDC module to apply the values in DYC09-12 directly to its outputs 1-4, respectively. Adjust the set-output value DYC09-12 (N40:121-124) that corresponds to the selected ram (screw) pressure valve, and observe actual pressure reported back in SYS26 (N40:178).
Page 122 Chapter 9 Span Your Valves Important: If downloading from your programming terminal, you must download INC first, followed by IPC (chapter 4). To download: Set: B21/7 B21/8 Test Valve Linearity with a Pressure vs. Time Injection Profile Confirm that your pressure setpoints are equal to one-half system pressure in IPC10, 14, 18, 22, 26, 30, 34, 38, 42, 46, and 50 (N44:66, 70, 74, 78, 82, 86, 90, 94, 98, 102, 106).
Page 123 Chapter 9 Span Your Valves To do this, change INC44, download INC followed by IPC with bits B21/7, 8, and repeat steps 3 and 4 as necessary. What You Have Accomplished The open-loop tuning procedure you just completed has defined the: range of ram (screw) pressure during injection end-of-range maximum and minimum signal levels for linear control of the injection pressure valve in open-loop control...
Page 124 Chapter 9 Span Your Valves Span Your Injection Span your flow valve for optimum velocity performance in three parts: Velocity Valve Confirm critical values Span your injection flow valve Test valve linearity with a velocity vs. position profile Important: You may omit the subsection Span Your Injection Flow Valve below if you have information from molding machine OEMs or hydraulic valve manufacturers on spanning the working range of valves.
Page 125: Span Your Injection Velocity Valve
Chapter 9 Span Your Valves Set New Values for the Velocity vs. Position Profile If necessary, refer to chapter 8 for when you determine the following: Velocity vs. position algorithm IPC03 B01 = B00 = 0 B38/96, 97 (chapter 8) Transition setpoints: Time limit IPC60 = above typical...
Page 126 Chapter 9 Span Your Valves ATTENTION: Be sure all machine guards and shields are in place before proceeding. Start by testing for maximum velocity and finding optimum values for INC46 and INC48 . Jog the ram (screw) all the way to the backpoint position. Set machine hydraulics to simulate injection.
Page 127 Chapter 9 Span Your Valves 10. After reaching the point where the maximum velocity starts to decrease, change the signal in INC48 just enough to restore the highest velocity referred to in step 4. Enter a new INC48 and repeat steps 7, 3, and 4 one last time.
Page 128 Chapter 9 Span Your Valves Test Valve Linearity with a Velocity vs. Position Profile Change your velocity setpoints to one-half maximum velocity (0.5 times the velocity in INC48) in these words: IPC09, 13, 17, 21, 25, 29, 33, 37, 41, 45, and 49 (N44:65, 69, 73, 77, 81, 85, 89, 93, 97, 101, 105).
Page 129 Chapter 9 Span Your Valves What You Have Accomplished The valve-spanning procedure you just completed has defined the: range of ram (screw) velocity during any injection profile end-of-range maximum and minimum signal levels for linear control of the injection velocity valve in open-loop control For this When trying to obtain The QDC module drives the selected...
Page 130: Span Your Pack And Hold Pressure Valves
Chapter 9 Span Your Valves Span Your Pack and Hold We recommend that you span your pack and hold pressure valves for Pressure Valves optimum pressure performance in four parts: Confirm critical values Span your pack and hold pressure valves Test valve linearity with a pressure vs.
Page 131 Chapter 9 Span Your Valves Confirm Your Configuration With These Words or Bits Pro Set Addr Worksheet for Hold Pressure QDC module output to which you connected your HDC02 B06, B05, B04 B38/212 214 (chapter 7) pressure control valve Set output values for unselected valves HDC09 12 = your values N44:185 188 All ramping is disabled with zero ramp rates...
Page 132 Chapter 9 Span Your Valves Span Your Pack and Hold Pressure Valves Span your pack valve for smooth operation at the highest desired pressure. Do this in the following procedure by finding optimum values for words: Title of Word Pack Word (Address) Hold Word (Address) Minimum Pressure Control Limit PKC41 (N44:157) HDC41 (N44:217)
Page 133 Chapter 9 Span Your Valves Enable set-output by changing DYC01-B08 (B34/392) from 0 to 1. This forces the QDC module to apply the values in DYC09-12 directly to its outputs 1-4, respectively. Adjust the value of DYC09-12 (N40:121-124) that corresponds to the selected ram (screw) pressure valve, and observe actual pressure reported in SYS26 (N40:178).
Page 134 Chapter 9 Span Your Valves 12. Download your final values for PKC41-44 and HDC41-44 to the QDC module by downloading the PKC, HDC, and HPC blocks. Important: If downloading from your programming terminal, you must first download PKC and HDC, followed by HPC (chapter 4). To download B21/9 B21/10...
Page 135 Chapter 9 Span Your Valves If the observed pressure HPS16 for pack and HPS33 for hold are still not within 20% of setpoints HPC16 and HPC33, your pressure valve is not linear over the desired range of operation. Correct for a non-linear valve by adjusting the Selected Pressure Valve, Output for Minimum: PKC43 for pack or HDC43 for hold as follows: If actuals are at least 20%: And Your Selected...
Page 136 Chapter 9 Span Your Valves Set Profile Pressure Alarms For Ram (Screw) Pressure – After spanning your pack and hold pressure valve, set profile maximum pressure alarm setpoints PKC57 (N44:173) for pack and HDC57 (N44:233) for hold equal to a ram (screw) pressure that should not be exceeded during either profile.
Page 137: Span Your Plastication Pressure Valve
Chapter 9 Span Your Valves Span Your Plastication We recommend that you span your plastication pressure valve for optimum Pressure Valve plastication performance in four parts: Confirm critical values Span your plastication pressure valve Test valve linearity with a plastication backpressure vs. position profile Set the profile pressure alarm Important: You may omit the subsection Span Your Plastication Pressure Valve below if you have information from molding machine OEMs or...
Page 138 Chapter 9 Span Your Valves Before proceeding, observe these warnings: ATTENTION: As with any machine start-up, make sure you installed a test mold in the machine. Programming errors, configuration errors, or hydraulic problems could lead to machine damage or injury to personnel. ATTENTION: Be sure all machine guards and shields are in place before proceeding.
Page 139 Chapter 9 Span Your Valves While observing actual pressure in SYS26 (N40:178) and the output in SYS41-44 (N40:193-196) that corresponds to the selected plastication valve, run a plastication backpressure vs. position profile. Do this by toggling DYC04-B08 (B34/408) from 0 to 1 to 0. With your programming terminal, record: maximum profile backpressure displayed in SYS26 (N40:178) Record here a) ___________...
Page 140 Chapter 9 Span Your Valves 10. Compare actual backpressures with your setpoints in PPC10, 14, 18, 22, 26, 30, 34, 38, 42, 46, 50 as follows: Then Actuals are greater than 1. Decrease PLC44 by 10%. setpoints by 20% or more 2.
Page 141 Chapter 9 Span Your Valves What You Have Accomplished The open-loop tuning procedure you just completed has defined the: range of ram (screw) backpressure during plastication end-of-range maximum and minimum signal levels for linear control of the plastication pressure valve in open-loop control For this When trying to obtain The QDC module drives the selected...
Page 142 Chapter 9 Span Your Valves Span Your Plastication We recommend that you span your plastication RPM valve for optimum RPM Valve plastication performance in three parts: Confirm critical values Span your plastication RPM control valve Test valve linearity with a plastication RPM vs. time profile Important: You may omit the subsection Span Your Plastication RPM Control Valve below if you have information from molding machine OEMs or hydraulic valve manufacturers on spanning the working range of valves.
Page 143: Span Your Plastication Rpm Valve
Chapter 9 Span Your Valves Before proceeding, observe these warnings: ATTENTION: As with any machine start-up, install a test mold. Programming errors, configuration errors, or hydraulic problems could lead to personal injury and/or machine damage. ATTENTION: Be sure all machine guards and shields are in place before proceeding.
Page 144 Chapter 9 Span Your Valves Copy initial values PLC09-12 into DYC09-12 (N40:121-124) of your PLC-5 data table with this exception: Important: Enter a value corresponding to zero RPM into the word DYC09-12 (N40:121-124) for output 1, 2, 3, or 4 that drives the selected screw RPM valve.
Page 145 Chapter 9 Span Your Valves While maintaining this minimum RPM, observe the actual set-output value in SYS41-44, (N40:193-196) that corresponds to your screw RPM valve. Copy this value into PLC47 (N44:403), the Selected RPM Valve, Output for Minimum. Modify the value in DYC09-12 (N40:121-124) that corresponds to the screw RPM valve in 5% steps while observing rising RPM in SYS27 (N40:179).
Page 146 Chapter 9 Span Your Valves At completion of the profile, observe the RPM actuals reported for the middle segments in PPS25, 29, and 33 (N44:729, 733, and 737). If the observed RPMs are not within 20% of the setpoints entered in PPC25, 29, and 33, then your RPM valve is not linear over the desired range.
Page 147: Tune Your Machine For Producing Parts
Chapter Tune Your Machine for Producing Parts Chapter Objectives In chapter 9 you ran simple open-loop profiles to span your valves. This chapter presents guidelines to help you adjust parameters in configuration and profile blocks to optimize machine performance for production runs. In this chapter, we consider the following items not covered previously.
Page 148: Closed Loop Control
Chapter 10 Closed loop Control So far, you ran open-loop profiles with the QDC module’s PID and VelFF control algorithms disabled. We suggest that you use open-loop control for: spanning valves troubleshooting machine performance when the machine has no pressure sensors for feedback Important: You can achieve considerably better consistency of finished parts when the QDC module operates in closed-loop control.
Page 149 Chapter 10 Use the highest possible P and I gain constants for repeatable performance without hammering your hydraulics First tune your proportional gain. Then add integral gain. Typically, the integral term will be larger than the proportional term. The QDC module’s pressure algorithm differs from classic PID algorithms. Use an oscilloscope, if available.
Page 150 Chapter 10 Slowly increase the integral term while running machine cycles until profile pressure actuals overshoot profile setpoints. Now decrease the integral term until overshoot disappear. Important: If you cannot make pressures actuals match entered setpoints, verify your Unselected Valve Set-output Values are correct for your application (Refer to chapter 7 and the discussion later in this chapter).
Page 151: Tune Closed Loop Velocity Control
Chapter 10 Important: If you cannot alter your proportional and integral terms so oscilloscope traces quickly level without bouncing, verify your Unselected Valve Set-output Values are correct. Refer to this topic later in this chapter or in chapter 7. Tune Closed loop General Guidelines for Velocity Tuning Velocity Control If your machine will never run velocity profiles, skip this section.
Page 152 Chapter 10 Tune Velocity Loops without an Oscilloscope Before you begin tuning your velocity loop, confirm that you: selected the velocity vs. position algorithm selected closed-loop control zeroed the velocity feedforward term did not change the proportional term that you entered in chapter 7 disabled ERC reset ERC values disabled ramping...
Page 153 Chapter 10 Tune velocity loops with an oscilloscope Before you begin tuning your velocity loops, confirm that you: selected the velocity vs. position algorithm selected closed-loop control zeroed the feedforward term did not change the proportional term entered in chapter 7 disabled ERC reset ERC values disabled ramping...
Page 154: Tuning Considerations For Production Parts
Chapter 10 Tuning Considerations In this section, we discuss the usage and effect of the following items: for Production Parts Profile Requirements Cushion, Shot Size, and Transition Setpoints Unselected Valve Set-output Values Logical Bridges and End-of-profile Set-output Values Decompression Pullback Acceleration and Deceleration Ramp Rates Watchdog Timer and Profile Offsets Pressure Alarm Setpoints...
Page 155 Chapter 10 Important: The injection velocity profile requires one additional velocity setpoint beyond the last non-zero end-of position setpoint, so you must program one more velocity setpoint than position setpoint, such that total velocity setpoints = total position setpoints + 1 If not, the ram (screw) stops at the final end-of-position setpoint (if it does not see a transition beforehand).
Page 156 Chapter 10 RPM Setpoints Use RPM setpoints only for the plastication RPM vs. position (or time) profile to control screw rotational speed and the temperature gradient of the melt. The resulting shear rate produces a barrel re-fill suited to the requirements of the next injection phase.
Page 157: Cushion, Shot Size, And Transition Setpoints
Chapter 10 Minimum Profile Requirements We present minimum requirements for inject-mode profiles. Use this as a starting point for developing your own part-specific profiles. Profile End of Segment Time Velocity Pressure Other Position Setpts Setpoints Setpoints Setpoints Setpoints Cushion, Shot Size, and Shot Size is the amount of molten plastic injected into the mold.
Page 158 Chapter 10 Shot Size (PPC61) Shot size (measured from cushion) is the amount of molten plastic needed to fill the mold (figure 10.3). Determine it with these general steps: Start with a shot size you know will NOT fill the mold. Enter a ram(screw) transition position about 1/2”...
Page 159: Unselected Valve Set Output Values
Chapter 10 Start of Zone for Pressure Transition (IPC64) A non-zero value (measured from mold end) forces the QDC module NOT to transition on pressure until the ram (screw) reaches this zone (figure 10.3). Use this setpoint to prevent nuisance pressure transitions due to pressure spikes during the early phases of the injection profile.
Page 160 Chapter 10 In chapter 7, you determined the signal output percentages required to drive the unselected valves during respective profiles. These values should allow desired ram (screw) control. Although different part set-ups and other process considerations may require that you modify them during a particular profile, you should adjust them only if you are unable to obtain desired closed-loop control by modifying profile tuning constants.
Page 161: Logical Bridges And End Of Profile Set Output Values
Chapter 10 Logical Bridges and In chapter 8, you configured your hold and plastication profiles to stop and End of profile set outputs for no flow or pressure at completion. If your hydraulics and/or Set output Values process require NO changes controlled by your PLC-5 processor before continuing a molding cycle, you may configure the QDC module to logically bridge the following profile/movement pairs as integrated machine phases:...
Page 162: Decompression Pullback
Chapter 10 Decompression Pullback Lengths for Pre- and Post-decompression Pullback (for pre decompression PRC05) (for post decompression PSC05) Pre-decompression separates plastic solidifying in the sprue from the molten cushion remaining in the barrel. The QDC module applies pre- decompression pullback to the ram (screw) after hold, before plastication. Post-decompression guards against drooling molten plastic into the open mold when the clamp is opening.
Page 163 Chapter 10 Figure 10.1 Example Injection, Pack, and Hold Profiles with Accl/Decel Ramps Important: When enabled, the QDC module applies ramp rates at the beginning of each profile segment. When moving from one profile to the next, the QDC module never applies ramps until it begins the next profile. With caution, you can use ramp rates to smooth out jerky motion present during large increases or decreases in pressure or flow.
Page 164: Watchdog Timer And Profile Offsets
Chapter 10 Watchdog Timer Profile Watchdog Timer Preset (PLC08) and Profile Offsets Set your plastication profile watchdog timer preset after your machine is running repeatable, quality parts. Set it just longer than the repetitive duration of the profile to warn that a process problem may be developing. For example, warn of a low feed level from the hopper.
Page 165: Pressure Limited Injection Velocity Vs. Position
Chapter 10 Pressure limited Injection Pressure-limited velocity vs. position differs from both velocity and Velocity vs. Position pressure injection control. During normal operation, pressure-limited velocity control acts the same as velocity vs. position control. However, when ram (screw) pressure exceeds a preset, the QDC module changes from velocity to pressure control to guard against flashing the mold.
Page 166 Chapter 10 You control the maximum pressure of the pressure-limited velocity vs. position profile with this setpoint: IPC57 – Ram Pressure Limit for Pressure-limited Velocity Control. When ram (screw) pressure reaches this limit and IPC58 and 59 allow it, the QDC module switches control from velocity to pressure control. Consider the following when determining this setpoint.
Page 167: Expert Response Compensation
Chapter 10 Expert Response The QDC module uses a proprietary, enhanced control scheme called Compensation Expert Response Compensation (ERC). It compensates for changes in your machine dynamics, machine hydraulics, raw materials, and other process variables. It also adjusts the open-loop and closed-loop control algorithms to compensate for abrupt upsets and long term deviations to your process.
Page 168: Troubleshoot With Leds
Chapter Troubleshoot with LEDs Chapter Objectives This chapter helpes you troubleshoot your QDC module using LED indicators. Use LEDs to Troubleshoot The front panel of the QDC module contains three Light Emitting Diodes Your QDC Module (LEDs). Use them for troubleshooting during integration or operation of the QDC module.
Page 169: Module Calibration
We recommend that you re-calibrate your QDC module every two years. To calibrate it yourself, refer to the Reference Manual, 1771-6.5.88 (dated November 1992), for calibration instructions. Otherwise, return it to the factory with this order number: 1771-QDC/(Rev Letter) – CAL. 11-2...
Page 170: Blank Worksheets
Appendix Blank Worksheets Workshet 3 A Select Module Parameters Code: Example: If you select Inject operation with English units: MCC02 = 00000000 00001000 Worksheet 3 B Select Input Ranges for your Sensors Code: Example: If you select an input range of 4-20mA for all four inputs, MCC03 = 11111111 10101010.
Page 171 Appendix A Worksheet 3 C Select Output Ranges for your Valves Code: Example: If you select 0-10 vdc for all four output ranges, MCC04 = 11111111 01010101. Important: Software input/output selections must match the jumper settings for each respective input/output.
Page 172 Appendix A Worksheet 3 D Determine Initial Sensor configuration Values Input Line Control Pro Set 600 Value Description Units Word Address...
Page 173 Appendix A Worksheet 3 E Final Sensor configuration Values Input Line Control Pro Set 600 Value Description Units Word Address...
Page 174 Appendix A Worksheet 3 F SWTL Configuration Values Control Word Pro Set 600 Addr. Value Description Units Worksheet 3 G Alarm and Time delay Setpoints Control Word Pro Set 600 Addr. Value Description Units...
Page 175 Appendix A Worksheet 5 A Ram (screw) Jog Configuration Values Control Block Pro Set 600 Addr. Value Description Units Word Inject, Forward Jog Inject, Reverse Jog Screw Rotate Jog Jog RPM and Pressure Alarms...
Page 176 Appendix A Worksheet 5 B Clamp & Eject Jog Configuration Values for QDC Module in Inject Mode Control Block Pro Set 600 Addr. Value Description Units Word Clamp, Forward Jog Clamp, Reverse Jog Ejector, Advance Jog Ejector, Retract Jog...
Page 177 Appendix A Worksheet 7 A Injection Configuration Block (INC) Code:...
Page 178 Appendix A Worksheet 7 A (continued) Injection Configuration Block (INC) Control Word Pro Set 600 Addr. Value Description Units...
Page 179 Appendix A Worksheet 7 B Pack Configuration Block (PKC) Code: A-10...
Page 180 Appendix A Worksheet 7 B (continued) Pack Configuration Block (PKC) Control Word Pro Set 600 Addr. Value Description Units A-11...
Page 181 Appendix A Worksheet 7 C Hold Configuration Block (HDC) Code: A-12...
Page 182 Appendix A Worksheet 7 C (continued) Hold Configuration Block (HDC) Control Word Pro Set 600 Addr. Value Description Units A-13...
Page 183 Appendix A Worksheet 7 D Plastication Configuration Block (PLC) Code: A-14...
Page 184 Appendix A Worksheet 7 D (continued) Plastication Configuration Block (PLC) Control Word Pro Set 600 Addr. Value Description Units A-15...
Page 185 Appendix A Worksheet 7 E Pre decompression Configuration Block (PRC) Control Word Pro Set 600 Addr. Value Description Units A-16...
Page 186 Appendix A Worksheet 7 F Post decompression Configuration Block (PSC) Control Word Pro Set 600 Addr. Value Description Units A-17...
Page 187 Appendix A Worksheet 8 A Injection Profile Block (IPC) Code: Control Word Pro Set 600 Addr. Value Description Units A-18...
Page 188 Appendix A A-19...
Page 189 Appendix A Worksheet 8 B Pack/Hold Profile Block (HPC) Code: A-20...
Page 190 Appendix A Worksheet 8 B (continued) Pack/Hold Profile Block (HPC) Control Word Pro Set 600 Addr. Value Description Units A-21...
Page 191 Appendix A Worksheet 8 C Plastication Profile Block (PPC) Code: A-22...
Page 192 Appendix A Control Word Pro Set 600 Addr. Value Description Units A-23...
Page 193 Index Symbols **Empty**, E-Stop, 2 11 end-of-segment setpoints, 8 20 tuning, 10 10 ERC, tuning considerations, 10 21 algorithm, select for profile, 8 18 error correction for, data entry in, data audience, blocks, Auxiliary analog inputs, flash prevention, backpressure setpoints, 8 20 gain constants (PID), 7 14...
Page 194 Index I–2 injection profile ramp rates for accel/decel, 7 17 benefits of, set-output values example benefits, end of profile, 7 18 unselected valve, 7 15 install QDC module, velocity control limit, 7 22 installation procedures watchdog timer presets, 7 26 ground the QDC module, worksheets for, install the QDC module,...
Page 195 Index I–3 logical bridges, 8 18 troubleshooting, 11 1 tuning, 10 15 QH module, record I/O ranges, numbering, bit and word, ram pressure setpoints, 8 14 ramp rates accel/decel tuning, 10 16 initial values, 7 18 offset, 8 21 related publications, sign, 8 18 tuning considerations,...
Page 196 Index I–4 tune closed-loop pack and hold pressure, 9 13 pressure control plastication pressure, 9 20 general guidelines, 10 2 plastication screw RPM, 9 25 with an oscilloscope, 10 4 velocity control limits, 7 22 without an oscilloscope, 10 3 velocity setpoints, velocity control tuning,...

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