Lenovo 10YC, Hardware Maintenance Manual, Page: 10 / 106

– Stand on suitable rubber mats (obtained locally, if necessary) to insulate you from grounds such as
metal floor strips and machine frames.
Observe the special safety precautions when you work with very high voltages; these instructions are in
the safety sections of maintenance information. Use extreme care when measuring high voltages.
• Regularly inspect and maintain your electrical hand tools for safe operational condition.
• Do not use worn or broken tools and testers.
• Never assume that power has been disconnected from a circuit. First, check that it has been powered-off.
• Always look carefully for possible hazards in your work area. Examples of these hazards are moist floors,
nongrounded power extension cables, power surges, and missing safety grounds.
• Do not touch live electrical circuits with the reflective surface of a plastic dental mirror. The surface is
conductive; such touching can cause personal injury and machine damage.
• Do not service the following parts with the power on when they are removed from their normal operating
places in a machine:
– Power supply units
– Pumps
– Blowers and fans
– Motor generators
and similar units. (This practice ensures correct grounding of the units.)
• If an electrical accident occurs:
– Use caution; do not become a victim yourself.
– Switch off power.
– Send another person to get medical aid.
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 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:
• Electrical hazards, especially primary power (primary voltage on the frame can cause serious or fatal
electrical shock).
• Explosive hazards, such as a damaged CRT face or bulging capacitor
• Mechanical hazards, such as loose or missing hardware
The guide consists of a series of steps presented in a checklist. Begin the checks with the power off, and the
power cord disconnected.
Checklist:
1. Check exterior covers for damage (loose, broken, or sharp edges).
2. Power-off the computer. Disconnect the power cord.
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M710q Hardware Maintenance Manual