BSS Audio FDS-318, User Manual

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!!! CAUTION - Important Notes !!!
SERVICE SECTION
!!! 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.
The primary of the mains transformer is protected against high voltage spike
interference by two voltage dependent resistors. These provide a short circuit
to voltage peaks in excess of their maximum rating.
Should the unit be inadvertently connected to 3 phase line/line voltages, or to
240V when selected to 120V, or any other incorrect voltage, these suppressors
are likely to fail in a protective short circuit mode. This will be demonstrated
by repeated mains fuse failure when powering up the unit.
Even in this case of extreme overvoltage the unit is protected against failure,
and the simple removal of these suppressors will allow the unit to be used
again. It is important that they are replaced as soon as possible to ensure
continued protection.
The two VDRs are mounted on a small circuit board attached to the rear panel
of the 120/240V selector switch.
Ensure that the unit is disconnected from the
mains power before removing the suppressors.
Figure 12.1 indicates the location and specification for the suppressors.
12.2 Transient
Suppressor
Replacement
Figure 12.1 Suppressor
location
The internal DC fuses are located around the mains transformer, and are
labelled FS1, FS2 and FS3.
The unit should be disconnected from the mains supply before the lid is
removed.
12.3 Internal DC
fuse check