PW 400 / PW 500 Portable Wheel Load Weigher Installation and Service Manual 37881
Contents 1.0 Introduction .............................................................................................................................. 1 1.1 1.2 1.3 1.4 2.0 Operation .................................................................................................................................. 3 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 3.0 General Description .................................................................................................... 1 Functional Description ...
1.0 Introduction This manual contains operating and service procedures for both the PW 400 and PW 500 Portable Wheel Weighers. 1.1 General Description The PW 400 and PW 500 Portable Wheel Weighers are microprocessor controlled, hydraulically operated, static weighers designed to measure weight applied anywhere within the weighing surface. The weighers are packaged in a rugged, corrosion resistant, lightweight enclosure specifically designed to meet the demand of daily outdoor operation.
1.3 Physical Description Overall length 20 1/2 inches Width, main body 14 inches Width, including handle 17 3/4 inches Width, weighing surface 10 1/2 inches (PW 400); 13 1/2 inches (PW 500) Length, weighing surface 11 inches Height, nominal 3 inches Height, maximum 3-1/8 inches Ramp slope angle 20 degrees Weight, complete unit 46 pounds (PW 400); 50 pounds (PW 500) Weighing capacity 20,000 pounds / 10,000 kilograms Accuracy As per NIST Handbook 44 ±50 Lbs. (0–2,500 lbs.) ±100 Lbs.
2.0 2.1 Operation Portable Weighing Procedures The PW 400/PW 500 Portable Wheel Load Weigher is specifically designed to indicate the weight of an individual wheel resting at any position within the weighing area. The operator must follow the basic principles of portable weighing in order to obtain accurate and reliable results. Improper weighing procedures can induce errors into the weighing process that are no fault of the weigher.
2.4 Wheel Placement Correct wheel placement is necessary for accurate weighing of vehicles. For best results, the ramp approach of each weigher should be firmly seated against the tires and the weigher platform centered with the wheel prior to driving the vehicle onto the weigher. Occasionally the outside tire has such low air pressure that the inside tire of a dual set does not clear the ground. This will give an erroneous reading since the inner tire is bearing part of the load.
ZERO and LCL/TTL Activates or deactivates the display backlighting. Press both buttons at the same time to turn the display backlighting ON or OFF. COMM Communication connector for connecting two or more weighers together for Local/Total function or remote communications. CHGR Connection for input to recharge weigher battery. Maximum charge is 13.5 VDC at 300 mA 2.
2.7 REMOTE OUTPUT MESSAGE “TOT # # # # # LB” MEANING Total weight in pounds. “TOT # # # # # KG” Total weight in kilograms. “REM LOW BATTERY” Battery of interconnected weigher is becoming low. Recharge at first opportunity. “REM RECHARGE” Battery of interconnected weigher is too low to provide accurate weight indication. Recharge before use. “REM ZERO ERR” Failure of interconnected weigher to zero. “REM OVER-RANGE” Output of interconnected weigher exceeds its capacity.
Following is the procedure for connecting four weighers together for total operation: 1. Turn off the weighers to be interconnected. 2. Attach a communication cable from weigher #1 to weigher #2. 3. Attach a communication cable from the breakout receptacle of the first cable to the #3 weigher. 4. Attach a communication cable from the breakout receptacle of the second cable to the #4 weigher. 5. Turn the weighers on. 6. Press the LCL/TTL button on any weigher. 7. The display will show “WAITING FOR COMM” . 8.
3.0 Maintenance The PW 400/PW 500 weigher is designed to give many years of trouble-free service. However, in cases where a large number of portable weighers are in constant use and facilities are available, it may be desired to perform in-house maintenance rather than returning units to the factory. By carefully following instructions, normal maintenance and repairs can be easily accomplished. 3.
3.2 Removing the Platform Snap rings (see #8 in Figure 2 below) are sealed at the factory with silicone sealer to ensure proper environmental protection of electronics. Before disassembly, remove seals with a pick or another sharp instrument. 1. Place weigher on a flat surface, bottom down. 2. Insert a 5/32” Allen wrench into the head of set screws (51) and, by rotating in counterclockwise direction, loosen both set screws one full turn. 3.
3.5 Removing the PC Board Use the following procedure to remove the PC board: 1. Remove the platform (see Section 3.2) and display cover (see Section 3.4). Wear a grounded wrist strap to prevent electrostatic discharge damage to PC board. 2. Unplug connectors J1, J2, J3, J5, J6 and J7. Take care to prevent damage to the connectors and wiring harness. 3. Remove four screws at PC board corners. 4. Lift out PC board.
3.6 Removing the Battery Use the following procedure to remove the battery from the weigher. See Figure 4 for component locations. 1. Remove the 6 screws (70) around the outer edge of the battery compartment cover (69). 2. Lift out battery (66) and unplug connector. 70 69 66 Figure 4 — Battery Removal 3.7 Inspection and Cleaning All weigher parts should be carefully cleaned and inspected prior to assembly to assure proper working conditions.
4. Inspect side load strips (24) for tightness in base and signs of wear. Side strips should be replaced when depth of wear exceeds 0.003 inch. 5. Inspect link retaining pins (47) for tightness in base and signs of wear. 6. At bottom of base assembly, check load strips (19) for tightness in base and signs of wear. Load strips should be replaced when depth of wear exceeds 0.003 inch. 7. Using a torque wrench, tighten diaphragm retaining screws (46) to 50 inch-pounds. 8.
3.14 Reassembling the Platform Use the following procedure to reassemble the weigher platform. See Figure 5 on page 16 for location of numbered parts. 1. Grease and replace lower load strips (19), retainers (17), needle bearings (20), and upper load strips (18), with chamfered corners on upper load strip facing links. 2. Grease platform buttons (43). 3. Carefully insert platform into base. 4. Holding platform and base together, turn the weigher upside down. 5. Insert spring housing (3) and springs (7). 6.
Apply force slowly and symmetrically. A weight applied quickly can far exceed the weigher limit. If using dead weight, align center line of weight to center line of scale. 7. If the weigher indication falls outside the tolerances given in Section 1.3 at any points, recalibrate the weigher following the calibration instructions given in Section 5.0 below. ! Caution 5.0 Calibration Instructions After performing the test outlined in Section 4.
15. This completes the calibration of the weigher. Verify calibration as instructed in Section 4.0, Calibration Verification. If weigher is still outside the tolerances specified in Section 1.3, turn the unit OFF and perform the steps required in Section 3.0, Maintenance. After completing Section 3.0, repeat steps 1 through 15 again. If the weigher is still outside the tolerances, return the weigher to Rice Lake Weighing Systems for adjustment. 16.
6.0 Replacement Parts This section contains an exploded view of the PW 400/PW 500 weigher followed by an associated replacement parts list. Callout numbers on the exploded view correspond to item numbers on the parts list. Some callouts are shown elsewhere in this manual for user convenience. When ordering replacement parts, be sure to include the full part number and quantity required.
13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 34 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 BEARING, Link (1-3/4") PISTON BUSHING, Link ASSEMBLY, Load Strip (2") RETAINER, Load Strip Resilient (2") LOAD STRIP, Upper (2") LOAD STRIP, Lower (2") NEEDLE BEARING, Load Strip ASSEMBLY, Base SUBASSEMBLY, Base BASE, Machined LOAD STRIP, Base Side (1") RING, Diaphragm Retainer GASKET, Base DIAPHRAGM ASSEMBLY, Dial Cover DIAL COVER, Machined LENS, Magnifying SWITCH PLATE
66 BATTERY, 12 VDC Rechargeable 68 GASKET, Battery cover 69 COVER, Battery 70 SCREW, Cover (#6-32 x 1/4 Flat Hd., 82° SS) 71 SWITCH, RST-OFF/ON 72 Communications Connector Assy. 73 SWITCH, Momentary Pushbutton, Zero and LCL/TTL 74 Cable Clamp 75 TAG, RST-ON/OFF, Zero, LCL/TTL 76 CHARGER CONNECTOR ASSY. 77 TAG, Comm. Chgr. 78 GASKET, CONNECTOR 79 CONNECTOR ASSY, Battery wires 80 DISPLAY ASSY. 81 NYLON, # 4 Shoulder Spacer 82 #4 - 40 x 1/2 Phillip Pan Hd. Scr. S.S.
PW 400 / PW 500 Limited Warranty Rice Lake Weighing Systems (RLWS) warrants that all RLWS equipment and systems properly installed by a Distributor or Original Equipment Manufacturer (OEM) will operate per written specifications as confirmed by the Distributor/OEM and accepted by RLWS. All systems and components are warranted against defects in materials and workmanship for one (1) year. RLWS warrants that the equipment sold hereunder will conform to the current written specifications authorized by RLWS.
