Performing A Power-Receptacle Safety-Check - IBM V03 Maintenance Information

4. Check the power cord for:
a. A third-wire ground connector in good condition. Use a meter to measure the third-wire ground continuity
for 0.1 ohm or less between the external ground pin and frame ground. The power connector ground wire
is fastened with a screw and star washer near the power supply. Repair as needed.
b. A second star washer must be between frame ground and the wire lug.
c. The power cord should be the appropriate type, shipped for the 4247 printer.
d. Insulation must not be frayed nor worn.
5. Remove the covers (see Covers).
6. Check that the power supply cover has not been removed nor tampered with.
7. Check for any obvious non-IBM alterations.
8. Check inside the unit for any obvious unsafe conditions, such as metal-filing contamination, water or other
liquids, or signs of fire or smoke damage.
9. Check for worn, frayed, or pinched cables.

Performing a power-receptacle safety-check

A trained service representative or a qualified electrician should perform all checks necessary to ensure safe
operation. These should include the following checks and any other required by local regulations.
v Check the ac voltage at all associated power receptacles (see "4247 Model V03 nominal ac input power
requirements" on page 12).
v Check the ac impedance to ground at all associated power receptacles.
See IBM Electrical Safety for IBM Customer Engineers , S229-8124, for the correct test equipment and procedures
before performing any of the following tasks:
v Checking ac voltage at all associated power receptacles
v Checking ac impedance to ground at all associated power receptacles
v Verifying the safety of any "temporary power tap"
Safety and environmental notices
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