Circuit Protections; Thermal Switch; Fuse; Lamp Cover Switch - promethean PRM-30A 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 switch

There is the thermal switch (SW90) inside of the projec-
tor to detect the internal temperature rising abnormally.
When the internal temperature reaches near 85˚C, the
thermal switch opens to stop the operation of the power
supply circuit.
The thermal switch can be reset itself automatically
when the internal temperature becomes normal.
When the internal temperature reaches near 55˚C, the
thermal switch returns automatically.

Fuse

A fuse is located inside of the projector. When the POW-
ER indicator is not lighting, the fuse may be opened.
Check the fuse as following steps.
The fuse should be used with the type listed right;
How to replace the fuse
1. T he fuse is placed on the filter board behind the main
board. Remove the cabinet top, terminal cover, AV
cover and main board.
. T ake the fuse off, and replace the new one with the
specified type.
Thermal switch
(SW90)
Lamp cover switch
(SW901)

Lamp cover switch

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 ass'y, place the lamp cover correctly
otherwise the projector can not turn on.
Fuse Part No.: 323 021 7804
tYPe t6.3AH 250V FuSe
LItteL FuSe INC. tYPe 21506.3
Fuse Part No, : 423 034 4101
tYPe t6.3AH 250V FuSe
Hollyland Co, Ltd. tYPe 50Ct063H
-5-
Fuse
(F601)