Precautions And Notices - Nokia 447ZiPlus Service Manual

1-1 SAFETY PRECAUTIONS
1) Observe all cautions and safety related notes located inside the display cabinet and on the display
chassis.
2) Operation of these displays with the cabinet removed involves a safety hazard from electric shock.
Work on the display should not be attempted by anyone who is not thoroughly familiar with
precautions necessary when working on high voltage equipment.
3) Do not install remove or handle the picture tube in any manner unless shatter-proof goggles are
worn. People not so equipped should be kept away while handing picture tube. Keep picture tube
away from the body while handing.
4) The picture tube is constructed to limit X-RADIATION to 0.5MR/HR.at 300 mA anode current. For
continued protection, use the recommended replacement tube only, and adjust the voltages so that
the designated maximum rating at the anode will not be exceeded.
5) Before returning a serviced display to the customer a thorough safety test must be performed to
verify that the display is safe to operate without danger or shock. Always perform an AC leakage
current check on the exposed metallic parts of the cabinet. Proceed as follows.
Connect the monitor power lead to the mains supply, via an isolation transformer, and switch on,
Using the test circuit shown in Fig1-1 measure the AC leakage current between each pole (L and
N) of the supply and all accessible metal parts. The earth leakage current must not exceed 3.5mA

1. PRECAUTIONS AND NOTICES

(Fig 1-1)
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