Cpu - Teledyne T360 Operation Manual

Troubleshooting and Service
8.5.8.5. CONTROL INPUTS – REMOTE ZERO, SPAN

8.5.9. CPU

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The control input bits can be tested by the following procedure:
1. Connect a jumper from the +5 pin on the Status connector to the x5V on the
Control In connector.
2. Connect a second jumper from the '-' pin on the Status connector to the A pin
on the Control In connector. The instrument should switch from SAMPLE
mode to ZERO CAL R mode.
3. Connect a second jumper from the '-' pin on the Status connector to the B pin
on the Control In connector. The instrument should switch from SAMPLE
mode to SPAN CAL R mode.
4. In each case, the T360 should return to SAMPLE mode when the jumper is
removed.
There are two major types of failures associated with the CPU board: complete
failure and a failure associated with the Disk on Module (DOM). If either of
these failures occur, contact the factory.
For complete failures, assuming that the power supplies are operating properly
and the wiring is intact, the CPU is faulty if on power-on, the watchdog LED on
the motherboard is not flashing.
In some rare circumstances, this failure may be caused by a bad IC on the
motherboard, specifically U57, the large, 44-pin device on the lower right hand
side of the board. If this is true, removing U57 from its socket will allow the
instrument to start up but the measurements will be invalid.
If the analyzer stops during initialization (the front panel display shows a fault or
warning message), it is likely that the DOM, the firmware or the configuration
and data files have been corrupted.
Teledyne API Model T360/T360M Operation Manual
07272B DCN6552