Precautions And Notices; Safety Precautions - Tatung CM-14SAS Service Manual

1. PRECAUTIONS AND NOTICES
1-1. SAFETY PRECAUTIONS
<1>
<2>
<3>
<4>
<5>
Observe all.cautions and safety related notes iocated inside the display cabinet and on the display
chassis.
Operation of these displays outside the cabinet or with the cover removed, involves a shock hazard
from the display power supplies. Work on the display should not be attempted by anyone who is
not thoroughly familiar with precautions necessary when working on high voltage equipment.
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 handling picture tube. Keep picture tube
away from the body while handling.
The picture tube is constructed to limit X-RADIATION to 0.5mR/HR at 300 microamperes 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.
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 Fig. 1-1, 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.
CONNECT TO
EXPOSED METAL PARTS
MEASURING CIRCUIT
RESISTANCE = 2000 ohms
Fig 1-1 AC LEAKAGE CURRENT TEST CIRCUIT