Checking customer voltage with customer CB off (wired)

Procedure

Prepare the multimeter to measure 1.0 V ac or less.
Measure the voltage between each pair of voltage pins on the mainline power cable connector at the DC-UPS end.
- For single-phase (200 - 240 V) ( A to B ). See Figure 1.
- For three-phase high voltage (380 - 415 V) ( A to B , B to C , C to A ). See Figure 2.
Did any voltage measure more than 1.0 V ac?
- Yes, inform the customer that one or more voltage pins on the customer supply measured greater than 1.0 V ac even though the circuit breaker is off. Do not continue until the voltage is less than 1.0 V ac.
- No, continue with step 3.
Figure 1. Single-phase mainline power connector at DC-UPS end

Figure 2. Three-phase high voltage (380 - 415 V) mainline power connector at DC-UPS end
Measure the voltage between each voltage pin and the ground pin on each mainline power cable connector at the DC-UPS end.
- For single-phase (200 - 240 V) ( A to C Ground, B to C Ground). See Figure 1.
- For three-phase high voltage (380 - 415 V) ( A to Ground, B to Ground, C to Ground). See Figure 2.
Did any voltage measure more than 1.0 V ac?
- Yes, inform the customer that one or more voltage pins on the customer supply measured greater than 1.0 V ac even though the circuit breaker is off. Do not continue until the voltage is less than 1.0 V ac.
- No. For three-phase high voltage (380 - 415 V), go to step 4. For single-phase continue with Checking customer voltage with customer CB on (wired).
Measure the voltage between the Neutral pin to the ground pin on each mainline power cable connector at the DC-UPS end.

Did any voltage measure more than 1.0 V ac?
- Yes, inform the customer that the neutral line measured greater than 1.0 V ac even though the circuit breaker is off. Do not continue until the voltage is less than 1.0 V ac.
- No. Continue with Checking customer voltage with customer CB on (wired).