Meter Maintenance
Domain 9: Meter Maintenance
This domain tests preventive and corrective maintenance within authorization limits.
Core rules
- Routine checks: clean cover, display, terminal tightness, seal integrity, battery or clock, communication and earthing.
- Do not open the meter body or calibration seal in the field; replace the meter or send it to an authorized laboratory.
- Tighten terminals to the specified torque; loose terminals cause overheating, voltage drop and burnt meters.
- Record meter number, seal number, reading, test results and replacement reason.
- Maintain spare meters, test equipment and calibration records.
Worked example
A terminal shows discoloration and a burning smell. Isolate the supply, prove dead and inspect the cable and terminal. If the meter terminal is burnt, replace the meter rather than only re-tightening it. Record the final reading and seal number, then update the consumer record. Reasoning: heat damage changes contact resistance and may recur; replacement restores safety and traceability.
Traps that cost marks
- Cleaning electrical parts with water.
- Using incorrect terminal torque.
- Resealing a meter without authority.
- Losing the removed meter's final reading.
- Ignoring a low-battery or clock warning on an electronic meter.