IBM NETVISTA 2251, Hardware Maintenance Manual

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Safety inspection guide
The intent of this inspection guide is to assist you in identifying potentially unsafe
conditions on these products. Each machine, as it was designed and built, had
required safety items installed to protect users and service personnel from injury.
This guide addresses only those items. However, good judgment should be used to
identify potential safety hazards due to attachment of non-IBM features or options
not covered by this inspection guide.
If any unsafe conditions are present, you must determine how serious the apparent
hazard could be and whether you can continue without first correcting the
problem.
Consider these conditions and the safety hazards they present:
v
Electrical hazards, especially primary power (primary voltage on the frame can
cause serious or fatal electrical shock).
v
Explosive hazards, such as a damaged CRT face or bulging capacitor
v
Mechanical hazards, such as loose or missing hardware
The guide consists of a series of steps presented in a checklist. Begin the following
checks with the power off, and the power cord disconnected.
1. Check exterior covers for damage (loose, broken, or sharp edges).
2. Power-off the computer. Disconnect the power cord.
3. Check the power cord for the following:
a. A third-wire ground connector in good condition. Use a meter to measure
third-wire ground continuity for 0.1 ohm or less between the external
ground pin and frame ground.
b. The power cord should be the appropriate type as specified in the parts
listings.
c. Insulation must not be frayed or worn.
4. Remove the cover.
5. Check for any obvious non-IBM alterations. Use good judgment as to the safety
of any non-IBM alterations.
6. Check inside the unit for any obvious unsafe conditions, such as metal filings,
contamination, water or other liquids, or signs of fire or smoke damage.
7. Check for worn, frayed, or pinched cables.
8. Check that the power-supply cover fasteners (screws or rivets) have not been
removed or tampered with.
Chapter 9. Related Service Information
131