Service Section; Transient Suppressor Replacement - BSS Audio DPR 404 User Manual

!!! CAUTION - Important Notes !!!

SERVICE SECTION

13.0 Service Section
13.1 Transient The primary of the input transformer is protected against high voltage spike
interference by two voltage dependent resistors (VDR). These provide a
suppressor
momentary short circuit to voltage peaks in excess of the normal power
replacement
voltage rating.
Should the DPR 404 be inadvertently connected to 3-phase line/line voltages
or to 240V when selected for 120V, or any other incorrect voltage, these
suppressors are likely to fail in a short circuit mode. This will be demonstrated
by repeated mains fuse failure at power up.
Even in this case of extreme over-voltage, the DPR 504 is protected against
failure, and the simple removal of the damaged suppressors will allow the unit
to be used again. It is important, however, that they are replaced immediately
to ensure continued protection.
Before attempting to remove the damaged suppressors, ensure that the unit is
unplugged and totally isolated from any power supply.
Figure 13.1 shows the suppressors location on the voltage selector board.
Fig 13.1 Suppressor
location
!!! WARNING - Refer all servicing to qualified service personnel !!!
Risk of electric shock if the unit is opened.
BSS Audio accepts no responsibility for injury
subsequent to opening of the unit.
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