Checking customer receptacle ground pin voltage and continuity with customer CB off (plug in)

Procedure

  1. Prepare the multimeter to measure 1.0 V ac or less.
  2. Measure the voltage at the customer's ac power outlet between the ground pin and the building ground. See Figure 1 or Figure 2 or Figure 3 for the ground pin  G .
    Note: The customer circuit breaker that supplies ac voltage to the customer ac power outlet should still be off.

    Is the voltage less than 1.0 V ac?

    • Yes, go to step 4.
    • No, continue with the following step.
    Figure 1. Single-phase, 200 - 240 V, 60A, IEC60309 customer outlet pins
    Single-phase, 200 - 240 V, 60A, IEC60309 customer outlet pins
    Figure 2. Three-phase low voltage (200 - 240 V) phase-to-phase, 60A, IEC60309 customer outlet pins
    Three-phase low-voltage 200-240V phase-to-phase, 60A, IEC60309 customer outlet pins
    Figure 3. Three-phase high voltage (380 - 415 V) phase-to-phase, 30A, IEC60309 customer outlet pins
    Three-phase high-voltage (380 - 415 V) phase-to-phase, 30A, IEC60309 customer outlet pins
  3. Voltage is present at a customer outlet with the customer circuit breakers off.
    DANGER
    Inform the customer that, even though the circuit breaker is off, voltage higher than 1.0 V ac is measured at the failing customer voltage outlet pins. Do not continue until the voltage is less than 1.0 V ac. (1003)
  4. Prepare the multimeter to measure 1.0 ohm or less of resistance.
  5. Measure the resistance between the customer AC power outlet ground pin and the building ground. See Figure 1 or Figure 2 or Figure 3.

    Is the resistance 1.0 ohm or less?