Rice Lake SURVIVOR OTR Series, Руководство по установке

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SURVIVOR OTR Flattop Truck Scale
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10.5 Grounding
All ground connections are connected to a single ground point. At minimum, a 10-gauge wire should run from a lug on the scale
to the single-point ground. Most ground locations are near the electrical power panel serving the scale equipment.
10.5.1 Grounding Inspections
1. Verify the ground system of the AC power supply (consult with the local power company if necessary).
2. Check the weighbridge grounds.
3. Check bypass cables at each load cell and clean/remove any corrosion if necessary.
4. Check continuity of the single ground wire back to the AC ground.
To avoid the existence of multiple zero references that can create transient issues with both data lines and weighing
components, single-point grounding is recommended.
10.5.2 Checking a Single-Point Ground
Verify the Ground System of the AC Power Supply
1. Using a multi-meter, check the resistance of the AC outlet ground to the actual AC power ground rod coming into the
building. The multi-meter should read less than 1 ohm.
2. Measure the AC voltage across the ground and neutral of the AC outlet. The result should be 0 volts AC, not to exceed
0.5 volts AC.
Following both of these procedures is recommended; however, completing one of the steps above should allow
an evaluation the quality of the ground. If grounding issues with the AC power supply are discovered, notify the
building owner and/or the power company.
Check the Scale Grounding
1. Make sure the scale and all peripherals are connected to a transient protection device such as an uninterruptible
power supply to deter voltage distortions.
2. Use a bare, 10-gauge copper wire connected to the frame of the scale platform and the grounding lug on the junction
box board, and run the copper wire back to the ground rod provided by the power company. The copper wire can be
buried underground from the scale to the AC ground.
3. Make sure a braided transient bypass cable is positioned across each load cell mount to ensure electrical transients
pass through the bypass cable instead of the load cells.
4. Measure the resistance between the scale sections and the AC ground, the reading should be less than 1 ohm.
Higher readings are typically caused by corroded connections.
5. Check the AC power supplied to peripherals such as remote displays, printers and computers. A remote device may
not have the same AC power source as the indicator. Each device may not be grounded to the same point.
6. Measure the resistance between the AC power ground-points. The multi-meter should read less than 1 ohm.
10.6 Calibration and Testing
A truck scale should be calibrated and tested by a state-licensed service agency using no less than 12.5% of the scale’s
nominal capacity or 25,000 lb of certified test weights. The scale’s calibration interval is determined by the frequency of use.
At minimum, truck scales should be calibrated and tested every six months. Each section of the scale should be tested.
Detailed test reports should be provided for the customer and government authorities.
IMPORTANT