Rice Lake RL1800 Series, Руководство по установке

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RL1800 Series Weigh Module Kit
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4.0 Troubleshooting
If system powers up and displays some type of stable digital readout that varies with the
load on the system, system problems are most likely caused by factors other than the load
cells. Load cells are usually blamed for a malfunctioning system, however, 90% of the
time the problem is mechanical.
If system can be calibrated but does not return to zero, loses calibration or demonstrates
non-linearity or non-repeatability, see Table 4-1 for possible causes and refer to the
following list of checks.
1. Check load cell module for debris restricting load cell movement or debris
between scale and structure.
2. Check overload stops for proper clearance.
3. Ensure tank/vessel and modules are plumb, level, and square at critical areas.
4. Check all piping and conduit for connections that restrict vessel movement.
5. If check rods are used, loosen all connections to finger-tight for testing.
6. Check load cell cables for physical or water damage.
7. Check all electrical connections, especially in the junction box.
If the problem is not found:
1. Check possible indicator malfunction by using a load cell simulator to input a
known good signal into the indicator.
2. Disconnect each load cell’s signal leads at the junction box and check individual
load cell outputs with a multimeter.
3. Check input/output impedances for comparison with load cell manufacturer’s
specifications.
If a problem still cannot be isolated:
1. Reconnect all but one load cell.
2. Replace the load cell with a load cell simulator. Alternate so that each load cell
is individually disconnected and replaced with a simulator. If there is a problem
with a particular load cell, the symptom should disappear when that load cell is
not to the simulator.
Symptom Possible Cause
No return to zero Mechanical binding or debris in seals or under load cells;
may have lost system calibration
Non-linearity Thermal expansion or deflection under load causing binding or side load
Non-repeatability Loose load cell mount; drifting caused by moisture;
load cell overload or shock damage; mechanical binding
Lost calibration Out of level or plumb; moisture problem; mechanical binding
Drifting readout Moisture in junction box, cables, or load cell; mechanical binding
Table 4-1. Troubleshooting