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All information contained within this publication is, to the best of our knowledge, complete and accurate at the time of publication. Rice Lake Weighing Systems reserves the right to make changes to the technology, features, specifications and design of the equipment without notice.
The CLS-420 is a rugged, dependable cargo lift scale that can withstand many years of repeated use. When mounted on a forklift, the CLS-420 saves time and money by allowing loads to be weighed immediately instead of carrying the load to a floor scale.
Do not operate or work on this equipment unless this manual has been read and all instructions are understood. Failure to follow the instructions or heed the warnings could result in injury or death. Contact any Rice Lake Weighing Systems dealer for replacement manuals. WARNING Failure to heed may result in serious injury or death.
1.2.1 Battery Disposal When using Lithium-ion batteries, be sure to observe the following precautions for disposal as stated in the material safety data sheet regarding lithium-ion batteries. Figure 1-2. Material Safety Data Sheet - Lithium Ion Batteries...
CLS Classes and ID Plates During the initial sale or installation of the CLS-420, remind the customer that they must have an updated ID plate on the forklift stating the new lifting capacity and center of gravity information. This is required per OSHA rules and regulations.
The indicator front panel consists of a large (1.8'', 44.5 mm), 6-digit, 7-segment LED display and 21 keys. Standard features of the CLS-420 include: • ON/OFF switch to increase battery life and cycle power to the junction box •...
Use front panel setup to change setpoint and UNITS to set the time and date. Entering the front panel setup mode can be done without breaking the seal. CLS-420 Technical Manual...
Indicator Operations Basic 420 operations are summarized below. Toggle Gross/Net Mode Press GROSS to toggle the display mode between gross and net. If a tare value has been entered or acquired, the net value is the gross weight minus the tare. Toggle Units Press to switch between primary and secondary units.
The iQube2 uses a lithium-ion battery. See Section 2.9 on page Wireless communication from the indicator to the iQube2 which is located on the scales angle bracket. Lithium-Ion battery housed in a battery box. Figure 1-5. Wireless Version of Communication CLS-420 Technical Manual...
Junction Box The latest CLS-420 includes an updated version of the iQube2 junction box. This design is built to allow service technicians to easily service the unit in the field. It also replaces the older style j-boxes, originally used in the CLS- 420.
Section 2.3 on page The CLS-420 is shipped from the factory with the scale already calibrated to the indicator. Minimal recalibration and adjustments may be necessary once the scale is installed onto the fork lift. Calibration steps are contained in Section 3.2 on page...
2.1.1 Unpacking One Scale Configuration Follow the instructions in Figure 2-2 for unpacking a one scale configuration. Scale Hardware component box Protective wood covering Wood shipping pallet Front pallet support Exploded view of components Hardware component box plastic banding Front pallet Protective wood covering...
DO NOT clip the plastic band from scale two until scale one is installed Step 6: Clip plastic bands from scale two. Step 7: Remove protective wood covering for second scale. Scale two is ready for installation. Figure 2-3. Shipping Pallets for Two Scales CLS-420 Technical Manual...
Some diesel models also provide 24 volts and electric forklifts provide 36 to 48 volts of power. The CLS-420 has a 9-36 VDC and a 10-60 VDC power supply option. Refer to the forklift user manual for its grounding specifications.
Failure to properly torque the bottom plate retaining bolts may result in bodily harm or damage to WARNING equipment. 8. Adjust the shim bolts so there is a minimal clearance between the bottom cleats and the scale carriage of 0.020-inch thickness. This can be measured by using the included feeler gauge. CLS-420 Technical Manual...
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Failure to adjust shim bolts to proper clearance of 0.020 inches may result in binding, poor accuracy or Important improper fit of attachment to forklift. Illustration shown is with part of the flexure removed to show shim bolt location. Shim bolts Scale carriage Bottom cleat retaining bolts...
Used with Scale Cover Assembly PN 162340 Figure 2-7. Connecting The Coiled Cable 1. Loosen the bolt holding the cover to the scale assembly and remove cover. 2. Assemble loop clamp kit to the coiled interface cable. CLS-420 Technical Manual...
3. Route the coiled cable through the clips on backside of carriage toward middle. For proper coiled cable routing, tighten the clips. Set the other end of the cable aside until the power/communication box is installed (See Section 2.8.2 on page 20).
Bonded Washer Bolt Side Brackets Figure 2-9. Mount Kit (PN 131630) To permanently lock the indicator mounting bolts, Rice Lake Weighing Systems recommends using ® Locktite 262. 1. Install side brackets to the mount plate, using isolation bumpers and hardware, in the order shown in Figure 2-9.
The CLS series cargo lift scale will not operate on a positive ground. Refer to the forklift user’s manual for further verify grounding requirements. If using the wireless version of the CLS-420, the CLS scale uses a supplied lithium-ion battery to supply power, Section 2.9 on page 23.
Do not route power cable close to fan blades. Do not route power cable close to objects that generate heat such as exhaust pipes. Figure 2-13. Areas to Avoid When Running Power Cable CLS-420 Technical Manual...
2.8.3 Power Cable to Battery Connection 1. An in-line fuse is included with the CLS-420. The fuse comes enclosed in an in-line fuse holder with a terminal connector. Connect the fuse assembly to the power cable assembly using the terminal connectors.
4. Check for proper signal cable clearance as the side shifter (if used), is moved back and forth. 5. After the power hook-up is completed, plug the power connector into the power/communication box. Do not obstruct the view of OSHA labels on the forklift when routing cables. CLS-420 Technical Manual...
2.8.5 Grounding Except for the power cord, all cables routed through the cord grips should be grounded against the indicator enclosure. 1. Install the grounding clamps on the grounding bar, using the ground clamp screws. Do not tighten the screws at this time.
The CLS scale uses a supplied lithium-ion battery to supply power to the indicator when using a wireless version of the CLS-420. The lithium-ion battery is located on the top of the cover plate in a painted enclosure. Replacement part numbers are as follows: Part No.
2.11 Charging the Lithium-Ion Battery The lithium-ion battery comes with a two-bay, level-3 stand alone smart battery charger, a DC power jack and AC power cord as shown in Figure 2-22. To calibrate the battery pack, press the button on front label.
• Never use a modified or damaged charger • Use only with the specified products Storage • Store in a cool, dry and well ventilated area Disposal • Regulations vary for different regions. • Dispose of in accordance with local regulations CLS-420 Technical Manual...
CLS-420 Calibration and Configuration While the functionality remains the same for a standard 420 digital weight indicator, there are certain setup options that need to be changed for the proper functioning of the CLS-series cargo lift scale. the specific setup (menu) options, which include calibration, serial, program and print formatting are in the configuration section of this manual.
CLS-420 Calibration The CLS-420 indicator can be calibrated using the front panel calibration procedure which consists of the following steps: • Zeroing the scale inclinometer LEFT TINE • Zero calibration • Entering the test weight value (left fork tine) • Calibration of cell #1 •...
To calibrate the indicator, the forklift tines must be in place as test weights are placed upon them. Use a level to ensure that the forklift tines are level prior to calibration. The test weight used to calibrate the CLS-420 cannot be greater than 2500 lb. To calibrate the indicator using the front panel, do the following: 1.
Digital Filter Cutout Threshold – specifies the filter threshold, in display divisions. When a specified number of consecutive scale readings (DFSENS parameter) fall outside of this threshold, digital filtering is suspended. if NONE is selected, the filter is always enabled. 10DD 20DD 50DD 100DD 200DD 250DD Table 3-2. Configuration Menu Parameters CLS-420 Technical Manual...
Units – specifies primary units for displayed and printed weight. Values are: lb=pound; kg=kilogram, oz=ounce, TN=short ton; T=metric ton, g=gram Primary Default: lb Secondary Default: kg Indicators sold outside North America are configured with KG for both primary and secondary units NONE Table 3-3. Format Menu CLS-420 Calibration and Configuration...
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Only) choices via keyboard To toggle between primary and secondary units, press the UNITS key. Multipliers are pre-configured within the indicator. Manual entry is only necessary when NONE is selected under UNITS. Table 3-3. Format Menu (Continued) CLS-420 Technical Manual...
3-5, illustrates the different serial settings used for CLS functionality and a basic 420 indicator. 2LCELL The SSCALE parameter on the serial menu must be set to 2LCELL for use with the CLS-420 Cargo Lift Scale. If it is set to OFF, then the 420 indicator will function with a standard 420 calibration menu.
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0-255, in tenths of a second (10 = 1 second). ECHO OFF - EDP Echo – enables or disables echoing of the serial commands sent to the indicator. ON - Printer Table 3-6. Serial Menu Parameters (Continued) CLS-420 Technical Manual...
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Allows selection of time format and separator. See level three parameter for descriptions. TIMFMT Time Format – specifies the format used to display or print the time 24HOUR or 12HOUR TIMSEP Time Separator – specifies the time separator character COLAN or COMMA Table 3-7. Feature Menu Parameters CLS-420 Calibration and Configuration...
Front panel access to setpoints. Specify OFF if setpoints will not be tested. ON enables operator to turn setpoints on/off, change value, or change BANDVAL via front panel entry during weigh mode. Table 3-8. Setpoint Menu Parameters CLS-420 Technical Manual...
The P EDP command returns the current displayed weight value to the EDP port, along with the units identifier. If the indicator is in an under-range or overload condition, the weight value is replaced with (overload) or &&&&&& :::::: (under-range). CLS-420 Calibration and Configuration...
Table 3-10. Status Codes Returned on the ZZ Command Continuous Output (Stream) Format Figure 3-5 shows the continuous output format sent to the 420 printer port when the STREAM parameter (SERIAL menu) is set to either EDP or PRN. Figure 3-5. Continuous Output Data Format CLS-420 Technical Manual...
Press setup switch and Enter key at the same time to reset configuration and calibration parameters to factory default values. Load cells must be recalibrated before using the indicator (see Section 3.0 on page 27). Table 3-11. Test Mode Menu Functions CLS-420 Calibration and Configuration...
(on) with low voltage (0 VDC) and can be driven by TTL or 5V logic without additional hardware. Use the DIG IN menu to configure the digital inputs. LED’s on the CPU board light when digital inputs are active. CLS-420 Technical Manual...
Section 3.9.3 on page For sealing purposes, this screw does not need to be sealed. Power Connection Coiled Cable Connection Connection Connection Battery Positive 10-36V +V (7.5v) Battery Negative Chassis Ground Table 3-15. Cable Pin Outs CLS-420 Calibration and Configuration...
The module is now set to factory defaults and in wired mode only. Reconfigure by connecting the indicator to a wired Ethernet network using the DeviceInstaller or browser. When complete, set the network mode back to Wireless Only. CLS-420 Technical Manual...
• The module creates a unique DHCP name from its MAC address. See Section 3.9.2 on page • The baud rate of both serial channels is set to 19200 to match the settings of the Mega 8 indicators. • The input and output buffers are always flushed. CLS-420 Calibration and Configuration...
3°. Angle • displays to indicate an overload or under load. Over Under Reset the indicator if any settings become corrupt to return to default settings. See Section 3.9.3 on page CLS-420 Technical Manual...
3.11 Front Panel Display Characters Figure 3-10 shows the 7-segment LED character set used to display alphanumeric characters on the 420 front panel. < & > Figure 3-10. Display Characters CLS-420 Calibration and Configuration...
Parts and Service 4.1 Daily Inspection Checklist Check scale carriage for loose, worn, bent or broken components. Inspect fork tines for damage. Check locking pins on fork tines. Inspect coiled cable for pinched, rubbed, stretched or damaged areas. ...
4.2.3 Junction Box with Quick Disconnects (PN 130826) 10 1 This cable assembly connect to J4 This cable assembly connect to J5 Figure 4-5. Junction Box with Quick Disconnects (PN 130826) Item No Part No Description 130000 Bushing, PG7 Cord Grip 33188 Conn, Ring Terminal 1/4in 36719...
4.2.4 Protective Angle with Battery Box Assembly Part of item 9 Figure 4-6. Protective Angle with Battery Box Parts Illustration CLS-420 Technical Manual...
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15627 Locknut, Black PCN9 97462 PCB Assembly, Battery 97463 Switch, Toggle sealed 126608 Insert, Foam Battery Box 99191 Decal, Rice Lake 15369 Standoff, FEM-FEM 6-32NC 36036 LED, Panel Mount Green 15626 Cable, Grip Black PG9 22087 Screw, Mach 6-32NCx3/8 125482...
CLS-420 Indicator CPU Board Replacement The indicator enclosure must be opened to connect cables for load cells, communications, digital inputs, and analog output. The 420 has an on/off switch for the load cells and processor functions. Before opening the unit, ensure WARNING the power cord is disconnected from the forklift battery power source.
NEMA 4X Polycarbonate Junction Box Maintenance The CLS-420 scale can use a NEMA Type 4X polycarbonate junction box. The junction box is located between the front and back panel of the scale and is covered by a metal cover plate on the top of the scale. Use the following procedures for replacing a junction box on the CLS-420.
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4. Disconnect the wiring from the bottom board. 5. Loosen the screws and standoffs to remove bottom board and replace with new board. 6. Tighten the screws and standoff to secure the new board. CLS-420 Technical Manual...
The bottom board which is shown in Figure 4-17 connects the wiring for both load cells one and two. Table 4-9 lists the wiring assignments for the bottom board. 7. Reconnect the wires to the bottom board per Figure 4-17 Table 4-9.
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KEY (N/C) POS (red) CLOCK (blue) DATA (brown) TEMP (green) NEG (black) Table 4-10. Top Board Wiring Connections J6 wiring is only used in the wireless version of the CLS series and goes directly to the battery box. CLS-420 Technical Manual...
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4.5.2 Junction Box Board Replacement and Wiring – One Board Style (December 2010 and Later) To access the board: 1. Using a Phillips head screwdriver, loosen the junction box cover and set the cover aside. 2. Disconnect the wiring from the board. 3.
Tabulation 10 Pin Receptacle (18) Quick Connect Cable Assembly Wire Color Position on J2 Wire Color Position on J4 and J5 Green Black White Green Blue Black White Empty Brown Orange Empty +3.3V Table 4-11. Wiring Connections CLS-420 Technical Manual...
IQube2 Junction Box Maintenance/Upgrade The iQube2 junction box is designed for use with the Rice Lake CLS-420 forklift scales and is a replacement for the junction box used on early models of the scale. The load cell connectors have been updated to improve serviceability.
22. Align the iQube2 junction box with the bolt holes in the scale and use an Allen wrench to tighten. 23. Place the cover plate in place and secure with a bolt and washer, and seal the unit. 1. Locktite® is a registered trademark of Henkel Technologies. CLS-420 Technical Manual...
4.6.3 iQube2.3 Cross References When identifying the correct junction box cross referenced part number, please provide the serial number of the scale so the Rice Lake Weighing Systems sales and service departments can track it to the correct top level part number sold.
Load Cell Maintenance This section describes procedures for replacing a load cell. The CLS-420 uses Rice Lake’s load cell, PN 125543. The following instructions must be followed exactly to allow for seamless and easy load cell replacement. Take all necessary safety precautions when installing or replacing the scale parts including wearing safety WARNING shoes, protective eyewear, and using the proper tools.
Use the following steps to replace a load cell. 1. Raise the forklift carriage slightly for fork removal. 2. Slide the forks to the center of the carriage to allow for removal. Set forks aside. Slide forks to the middle of scale carriage Figure 4-27.
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Clean off any paint using a wire brush and oil. 15. Oil the spherical washers using a standard machine shop oil. 16. Disconnect the load cell cable from the junction box. 17. Loosen cable clips and remove the load cell. CLS-420 Technical Manual...
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Detach load cell clip from back plate of scale using a large screwdriver. Figure 4-31. Load Cell Cable Clips 18. Back off upper and lower overload stops using a 1 1/8" wrench. Overload stops looking at top view. Figure 4-32. Overload Stops 19.
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Figure 4-35. Use Chisel to Hold the Load Cell in Straight 25. Install the spherical washer set and hex nut on the bottom flexure rod, ensuring that the thick washer is mounted towards the mounting block. CLS-420 Technical Manual...
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Figure 4-36. Install Spherical Washer Set 26. Insert a flat-bladed screwdriver in the upper mounting block between the hole and the flexure rod, forcing the flexure rod in the same direction of the flexures. Insert the flat-blade screwdriver here to help center the flexure rod.
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37. Place a weight in the center of the fork and check side to side values. The weight values must be equal to complete the load cell replacement. 38. Tighten the overload stops when complete. 39. Calibrate the load cells (See Section 3.2 on page 28). CLS-420 Technical Manual...
4.7.3 Forklift Flexure Troubleshooting - 28" and 34" Models For Part Number 92828 The forklift flexure is designed to protect the load cell from damage in the forklift environment. Use the following steps if the forklift scale is out of tolerance or unable to return to zero on a consistent basis. 1.
LED Functions Below is a list of diagnostic LEDs for the 420. See Figure 4-11 on page 62 for locations on the 420 CPU board. Serial Port Status LED1 (EDP Port) Flashing red = TXD activity Flashing green = RXD activity On steady or off = No activity LED2 (PRN Port) Flashing red = TXD activity...
Load cell errors Test mV/v levels, at 1.5 mV per 1,000 lb, test at 350 ohms Weight inaccurate Tare key has been activated At a stable zero weight, press the TARE key to return scale to normal weighing mode. CLS-420 Technical Manual...
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Symptom Possible Cause Action Scale not returning to zero (0) Forks are touching the ground. Lift forks off ground, press the Zero key. Debris between the scale and the forklift Remove debris carriage. Debris between the front and back scale Remove debris plates.
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May have to grind or torch side of forklift carriage due to previously installed side shift protection method. Scale displaying negative Forks are resting (even slightly) on the Lift forks up off floor. weight floor. CLS-420 Technical Manual...
Table 5-1 lists these messages and their meanings. Error Message Description Solution E A/D A/D physical error Call Rice Lake Weighing Systems (RLWS) Service. EEPERR EEPROM physical error VIREE Virgin EEPROM Use TEST menu to perform DEFLT (restore defaults) procedure, then calibrate scale.
6.0 CLS-420 Specifications communication Power Consumption 1.5 A Printer Port Full duplex RS-232 or active transmit Fusing Internal short circuit protection only 20 mA current loop 2.5 A 5 x 20 mm fuse Both Ports 38400, 19200, 9600, 4800, 2400, Analog Specifications 1200, 600, 300 bps;...
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Specifications subject to change without notice. Rice Lake Weighing Systems is an ISO 9001 registered company. 230 W. Coleman St. • Rice Lake, WI 54868 • USA U.S. 800-472-6703 • Canada/Mexico 800-321-6703 • International 715-234-9171 • Europe +31 (0)26 472 1319 www.ricelake.com...
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