Circuit Protections; Thermal Fuse (Sw902); Lamp Cover Switch (Sw901); Fuse (F601) - Panasonic PT-VX500U Service Manual

Circuit Protections

This projector provides the following circuit protections to operate in safety. If the abnormality occurs inside the pro-
jector, it will automatically turn off by operating one of the following protection circuits.

Thermal fuse (SW902)

There is a thermal fuse (SW902) inside of the projector to detect the
internal temperature rising abnormally. When the internal tempera-
ture around lamp reaches near 113˚C, the thermal fuse will open to
cut off the power supply to the lamp power circuit.
If the thermal fuse opens, the projector cannot turn on. Thermal
fuse replacement is required.

Lamp cover switch (SW901)

The lamp cover switch (SW901) cuts off the drive signal to the lamp
circuit when the lamp cover is removed or not closed completely.
After opening the lamp cover for replacing the lamp assy, place the
lamp cover correctly otherwise the projector can not turn on.

Fuse (F601)

A fuse is located inside of the projector. When the ON(G)/
STANDBY(R) indicator is not lighting, the fuse may be opened.
Check the fuse as following steps.
The fuse should be used with the following type;
Fuse Part No.: 423 035 3004
TYPE T8AH 250V FUSE
LITTEL FUSE INC. TYPE 0215008.MXEP
or
Fuse Part No, : 424 007 3909
TYPE 8AH 250V FUSE
SKY-GATE, Ltd. TYPE SG5013008P-R
How to replace the fuse
1. The fuse is placed on the AC 1ST FILTER board. Remove the
cabinet top, MAIN&AV board following the "Mechanical Disas-
sembly" .
2. Take the fuse off , and replace the old one with the specified
type.
Thermal fuse
(SW902)
-7-
Lamp cover switch
(SW901)
Fuse
(F601)