PREFACE This Installation and Operation Guide provides installation and operation instructions for the CTI 2451 Eight Channel Thermocouple Input Module for SIMATIC® 405 programmable controllers. We assume you are familiar with the operation of SIMATIC® 405 Series programmable controllers. Refer to the appropriate SIMATIC®...
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CTI 2451 Installation and Operation Guide...
Notes alert the user to special features or procedures. CAUTION: Cautions alert the user to procedures which could damage equipment. WARNING: Warnings alert the user to procedures which could damage equipment and endanger the user. CTI 2451 Installation and Operation Guide...
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CTI 2451 Installation and Operation Guide...
CHAPTER 1. DESCRIPTION The Model 2451 Eight Channel Thermocouple Input Module is a member of Control Technology's family of I/O modules compatible with the SIMATIC® 405 Series programmable controllers. The Model 2451 is designed to translate Type "J" thermocouples, Type "K" thermocouples and millivolt input signals into equivalent digital words which are then sent to the programmable controller (PLC).
"overrange". The first 8 bits (20-27 octal) of the upper 16 bits are used for channel status and are read as X values. Bits 30-37 (octal) are not used. Figure 3 Word Map CTI 2451 Installation and Operation Guide...
Similarily an input below 0 degrees C for Type "J" or 0 degrees C for Type "K" will cause the overrange bit to be set. A temperature of 0.1 degree C will be returned to the PLC for Type "J" and Type "K". Figure 5 Effect of Temperature Input on Module Performance CTI 2451 Installation and Operation Guide...
The module has a resolution of approximately 0.2 degrees C, 0.4 degrees F or exactly 0.02 millivolts. The chart below shows the corresponding input resolution for each of the input configuration modes: Figure 7 Input Resolution CTI 2451 Installation and Operation Guide...
Open the shipping carton and remove the special anti-static bag which contains the module. After discharging any static build-up, remove the module from the anti-static bag. Do not discard the anti-static bag. You will need it for the following configuration procedure. CTI 2451 Installation and Operation Guide...
3. Selecting digital filtering or no filtering for the module 4. Logging the configuration jumper settings for future reference Each of these steps is described in the following sections. CAUTION: DO NOT attempt to calibrate. Figure 8 Jumper Locations CTI 2451 Installation and Operation Guide...
Locate the Digital Filtering Jumper JP34 (see Figure 8). To enable digital filtering, set the jumper in the ENABLED position. Since many analog input signals contain noise, CTI recommends using digital filtering unless maximum response time is required. Figure 9 Factory Configuration Jumper Settings CTI 2451 Installation and Operation Guide...
Thermocouple input signals are accepted through a screw terminal connector block located on the front of the module. Consult the thermocouple manufacturer's recommendations for selecting the input wire Figure 10 Screw Terminal Block Wiring type and size. CTI 2451 Installation and Operation Guide...
Avoid bending the wire into sharp angles. Use wireways for wire routing. When using shielded wires, ground them only at the module end for better noise immunity. Place wires so that they do not interfere with existing wire. CTI 2451 Installation and Operation Guide...
All unused channels should be shorted from the + to the - terminals to prevent saturation of the input amplifier. Failure to do so will result in erroneous readings on adjacent channels. Figure 11 Thermocouple Wiring Example The shields of both thermocouples are connected to terminal 3 GND connector. CTI 2451 Installation and Operation Guide...
All unused channels should be shorted from the + to the - terminals to prevent saturation of the input amplifier. Failure to do so will result in erroneous readings on adjacent channels. Figure 12 Millivolt Wiring Example CTI 2451 Installation and Operation Guide...
(as shown in Figure 14). The data bits from one channel and only one channel are transferred to Figure 14 Active Channel Bits the CPU with each CPU scan. The active channel indicators indentify which channel corresponds to those data bits. CTI 2451 Installation and Operation Guide...
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CPU is synchronous with the CPU scan. That is, the selected channels are presented to the CPU one at a time (one per CPU scan) in a cyclic fashion. Figure 16 Example Measurement CTI 2451 Installation and Operation Guide...
X0-X17 can be read as V-memory location 40400. Refer to the memory map in the Series 405 User Manual for details. NOTE: Only one channel is accessed per CPU scan. The active channel is incremented to the next selected channel following each CPU scan. Figure 17 Ladder Diagram Example CTI 2451 Installation and Operation Guide...
PS ..........01 ..(435) : CPU AND P/S FROM P/C EXIT-F1 READDK-F3 WRITDK-F4 READPC-F5 WRITPC-F6 AU/MAN-F7 CLRBS- CTI 2451 Installation and Operation Guide...
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If the line is listed as an empty slot or shows erroneous data, re-check the module to ensure that it is firmly seated in the slots. Generate the PLC memory configuration chart again. If the line is still incorrect, contact your local distributor or CTI at 1-800-537-8398 for futher assistance. CTI 2451 Installation and Operation Guide...
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CTI 2451 Installation and Operation Guide...
Failed I/O" or "Show PLC Diagnostics" support functions. If after consulting the chart above and you are unable to diagnose or solve the problem, contact your local distributor or CTI at 1-800-537-8398 for further assistance. CTI 2451 Installation and Operation Guide...
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CTI 2451 Installation and Operation Guide...
Common Mode Rejection: Greater than 110 dB @ 60 Hz (digital filtering disabled) Greater than 160 dB @ 60 Hz (digital filtering enabled) Normal Mode Rejection: Greater than 45 dB @ 60 Hz (digital filtering enabled) CTI 2451 Installation and Operation Guide...
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Field Wiring Connector: Accepts 14-26 AWG Mechanical: Size single-wide 405 module Operating Temperature: 0° to 60°C 32° to 140°F Relative Humidity: 5% to 95% non-condensing Shipping Weight: 0.5 lbs. Specifications subject to change without notice. CTI 2451 Installation and Operation Guide...
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USER NOTES CTI 2451 Installation and Operation Guide...
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CTI. Control Technology Inc. reserves the right to make changes to the Product in order to improve reliability, function, or design in the pursuit of providing the best possible Product. CTI assumes no responsibility for indirect or consequential damages resulting from the use or application of this equipment.
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CTI 2451 Installation and Operation Guide...
Failure to observe static control precautions may void the warranty. For additional information on static control precautions, contact CTI's main office at 1-800-537-8398. CTI 2451 Installation and Operation Guide...
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