Precautions and notices – Philips 107B7 User Manual

Page 7

17” CDT Color Monitor 107B7

2. Precautions and notices

2-1.Safety precautions

1. Observe all caution and safety related notes located inside the display cabinet.

2. Operation of the display with the cover removed, may cause a serious shock hazard from the display power

supply. 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 who are not so equipped should be kept away while handling picture tube. Keep picture tube away

from the body while handling.

4. The picture tube is constructed to limit X-RAY radiation to 0.5 mR/HR. For continued protection, use the

designated replacement tube only, and adjust the voltages so that the designated maximum rating at the

anode will not be exceeded.

5. Symbol“ “ means safety relative parts. The use of substitute replacement parts which do not have the

same characteristics as specified in the parts list may create shock, fire or explode etc.

6. Symbol“ ” means X-ray relative parts. Before replacing any of these components please read the parts

list in this manual carefully to avoid creating higher anode voltage or x-ray. Especially for sealed controls,

such as VR902 and FBT screen VR etc, which were sealed by the manufacturer once their optimum

position has been set, please don’t dismantle them as your likes, otherwise you will break or damage the

component. If you need replace the parts with sealed control, please adjust the relative VR to make sure the

B+ voltage about 53.5.0V and well seal it with A+B glue or equivalent, which you can not move away with

one screw driver

7. 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, such as screw heads.

Test method for current leakage is described as follow.

(a) Plug the AC line cord directly into rated AC outlet (do not use a line isolation transformer during this

check).

(b) Use an AC voltmeter having 5000 ohms per volt or with more sensitivity in the following manner:

Connect a 1500 ohms 10 Watt resistor, paralleled by a 0.15UF, AC type capacitor between a known

good earth ground (water pipe, conduit, etc.) and the exposed metallic parts simultaneously. Measure

the AC voltage across the combination of 1500 ohms resistor and 0.15UF capacitor.

part.

(d) Voltage measured must not exceed 0.5 volts RMS. This corresponds to 0.35 milliamp AC. Any value

exceeding this limit constitutes a potential shock hazard and must be corrected immediately.