Emerson Rosemount CCO 5500, Reference Manual

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3. If the blade is not spinning, measure the supply to the chopper motor voltage at the
test points M+ and M- on the circuit board (
Figure 5-5 ).
The voltage should read approxmately 1 Vdc. If the voltage is good, replace the
chopper motor. If the voltage is not 1 Vdc, the source unit electronics are suspect.
6.4 LED indications
If you suspect instrument malfunction, there are LEDs within the instrument indicating
various power rails and equipment operations.
LEDs Description
Control unit LEDs
5 V, -15, +15 Situated top/left of processor. Should all be ON ,
indicating that the power supplies to the instru-
ment are functioning correctly.
M-DIR Should operate approximately every 4 seconds.
SOL_MDRV Supply to the solenoid that drives the filter into
the optical path within the receiver pulses every
time the M-DIR changes (approximately every 2
seconds).
+V1, -V1, and +12 V Middle bottom left of board. All should be
ON
.
Power supplies to the isolated analog current
output.
+12 V Bottom left of board. Should be ON . Indication
of the isolated supply for the plant status input.
PS Bottom left of the board. In normal operation,
this LED should be
OFF . During plant-off periods,
however, if the plant status is being used, this
LED illuminates, and the rolling averages are not
updated.
Receiver LEDs
+V and -V These LEDs should be
ON
indicating that the
power supplies within the unit are functioning
correctly.
Source LEDs
+V and -V These LEDs should be
ON
indicating that the
power supplies within the unit are functioning
correctly.
Troubleshooting
Reference Manual 97