Comtech EF Data RCU108 - Manual (Page 29)

RCU108 1:8 Protection Switch Maintenance
TM066 - Rev. 1 Page 4-1
Section 4 - Maintenance
4.0 Periodic Maintenance
The RCU108 requires no periodic field maintenance procedures. The unit contains no
adjustments. Should a unit be suspected of a defect in field operations after all interface signals
are verified, the proper procedure is to replace the unit with another known working unit. If this
does not cure the problem, faulty cabling or power should be suspected.
A fault in the operation of the RCU108 should become evident through an illogical LED
indication on the front panel. For example, failure of the RF transfer switch will become obvious
when the ERROR LED becomes illuminated. This can be confirmed via the Front Panel of the
Backup Converter using the Switch Fault Menu. In this case, the RCU108 logic has commanded
the transfer switch to a certain position, but the relay remains stuck in the old position.
Verification of the operation of the IF and RF transfer switches can be verified through a DC
continuity check at the BNC and RF connectors at the rear of the RCU108. The RF and IF cables
will need to be removed to perform this test. Failure of either the IF or RF transfer switch can be
verified by checking the voltage to the coils on either relay assembly. The IF transfer switch coil
should have 4.5 Vdc and the RF transfer switch Coil should have 14.0 Vdc across the coil (not to
ground). If a fault in either the RF or IF transfer switch module is suspected, these assemblies
can be changed in the field.