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__ 2. Have the customer locate and turn off the branch circuit breaker and attach tag S229-0237, which
reads "Do Not Operate."
Note: All measurements are made with the receptacle faceplate in the normally installed position.
__ 3. Some receptacles are enclosed in metal housings. On receptacles of this type, perform the
following steps:
a. Check for less than 1 volt from the receptacle case to any grounded metal structure in the
building, such as a raised-floor metal structure, water pipe, building steel, or similar structure.
b. Check for less than 1 volt from receptacle ground pin to a grounded point in the building.
Note: If the receptacle case or faceplate is painted, be sure the probe tip penetrates the paint and
makes good electrical contact with the metal.
__ 4. Check the resistance from the ground pin of the receptacle to the receptacle case. Check
resistance from the ground pin to building ground. The reading should be less than 1.0 ohm, which
indicates the presence of a continuous grounding conductor.
Note: If measured impedance is greater that 1 ohm and the test instrument used was a digital
multimeter, verify that the grounding impedance is correct by using an appropriately
approved ground-impedance tester.
__ 5. If any of the checks made in substeps 2, 3 and 4 are not correct, ask the customer to remove the
power from the branch circuit and make the wiring corrections; then check the receptacle again.
__ 6. Check for infinite resistance between the phase pins. This is a check for a wiring short.
CAUTION:
If the reading is other than infinity, do not proceed! Have the customer make necessary
wiring corrections before continuing. Do not turn on the branch circuit CB until all the
above steps are satisfactorily completed.
__ 7. Have the customer remove tag S229-0237, which reads "Do Not Operate" and turn on the branch
circuit breaker.
Note: If your power source does not have a standard receptacle, check for voltage using local
procedures.
Measure for appropriate voltages between phases. If no voltage is present on the receptacle case
or grounded pin, the receptacle is safe to touch.
__ 8. With an appropriate meter, verify that the voltage at the outlet is correct.
Note:
v For 200-240 V, the acceptable phase-phase voltage measurement range is 180-254 V.
v For 380-415 V, the acceptable phase-phase voltage measurement range is 342-440 V.
v For 480 V, the acceptable phase-phase voltage measurement range is 432-509 V.
__ 9. Verify that the grounding impedance is correct by using the ECOS 1020, 1023, B7106, or an
appropriately approved ground impedance tester.
__ 10. Have the customer turn off the branch circuit breaker and attach tag S229-0237, which reads "Do
Not Operate."
14
Eserver pSeries 670 Installation Guide
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