Instructions Manual

Pub. #OM17-MSP3
6-30
Figure 12.2 External Controller circuit board (metal cover removed)
2. Turn off power to External Controller, remove clear lid and remove and replace any fuse
that has failed.
3. Check voltage with a digital voltmeter at power supply connection
All functions must be engaged during this test. In manual mode turn on wash pumps and cycle
sampler shoe hydraulics while holding voltmeter leads on power supply connector shown in Figure
3. Keep moisture from entering External Controller. It may be necessary to reposition the spray
nozzles or shield the overspray from the Controller. It is critical that the pumps are under full load
(pumping water through the nozzles) during this test. Be careful to not let your fingers or voltmeter
leads touch any other component inside the External Controller.
POWER (12V)
FUSE 2 (10A)
and its LED
FUSE 1 (500 mA)
and its LED
5V 2
12V C
5V
Figure 12.3 Using
voltmeter to check
voltage at External
Controller power supply