WiremanWireman · Service & power quality troubleshooting · 2023 NEC ·
Service & power quality
Lost legs, open neutrals, low or high voltage, surges.
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Half the house is outSome circuits dead, others fine, and 240 V appliances won’t run. Usually a lost leg.Up to 2 stepsNo power to the whole buildingEverything is dead. Find out fast whether it’s the utility, the meter, or the main.Up to 4 stepsOpen or loose service neutralLights brighten and dim as loads switch, electronics die, or current shows up on water pipes. Find where the neutral is failing.Up to 4 stepsVoltage too high or too lowMeasured voltage outside the normal range, or sagging under load. Service, feeder, branch circuit or a system mismatch.Up to 3 stepsSurges and electronics keep failingTVs, routers, boards and drivers dying. Sort out surges, high voltage, a bad neutral and grounding differences between systems.Up to 3 stepsLights dim when the A/C startsA blink or a long dip every time the compressor starts. Normal inrush, a hard-starting compressor, or too much resistance in the supply.Up to 3 stepsNeutral overheating from harmonicsA hot neutral or transformer with balanced phases. Triplen harmonics from electronic loads adding on a shared neutral.Up to 4 stepsMeter base problemsBurned jaws, water in the socket, a dead or damaged meter, or a lost leg at the meter. What’s yours and what’s the utility’s.Up to 2 stepsUtility side or customer side? Who fixes whatFind the service point and sort the problem: utility, customer or shared, and what to do first.Up to 2 steps