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TPCMQ48 SERIES
INSTALLATION & OPERATING MANUAL
Manual No. tpcmq48-4
tpcmq48-man-rev4-0116.indd
18.0 MAINTENANCE
No routine maintenance is required on the TPCMQ48 series except for periodic cleaning of dust
and dirt around the front ventilation grill. A small vacuum nozzle should be used for this purpose.
19.0 SETUP AND TESTING
19.1
The TPCMQ48 can be initially tested mounted in a rack or on a test bench. If two or more
units are to be tested in a rack, they should first be individually tested in Position 1 (left
side) of the rack.
19.2
With the input power source turned off, connect input power wires to the DC input terminals
of the mating interface board, the TPCMQ48 mating connector or in the case of a power
shelf the input terminal block. Make sure that the safety ground wire is connected. Do not
touch the output terminals when DC input power is present.
19.3
Connect a resistive power load across the proper output pins, terminals or bus bars. The load
should be 20% to 50% of the full load value and can be either a power resistor or electronic
load set to the resistive mode. Make sure that the power resistor has adequate heat sinking
and cooling.
19.4
Connect a color-coded, twisted pair (22 or 24AWG) from the remote sense pins to the load.
The +Ve Sense must go to the positive side of the load and the –Ve Sense to the negative
side of the load. Also connect the Enable pin to the -Ve Sense. This must be done for the
unit to operate. When using the mating interface board or a power shelf, the Enable pin is
automatically connected to -Ve Sense. The units are then controlled by the Inhibit inputs.
19.5
Checking Front Panel LEDs
- With the TPCMQ48 module on the bench or in Position A
of the power shelf, turn on (or plug in) the power source. The two LEDs should be on. If
either is not the case see section 8.2 on page 8 of this manual to determine a possible cause.
19.6
Checking the Output Voltage
- Measure the output voltage at its load with a digital voltmeter.
The voltage should be within ±1% of its nominal value.
19.7
Checking the Inhibit Input
- Unplug the input power source. Connect a wire from the
Inhibit input to Standby Return. Turn the input power source back on. The Output power
Good LED should be off and the Input Power Fail LED should be on. Check the output
voltage with a digital voltmeter. It should read zero volts.
19.8
Checking the Input Power Fail and Output Power Good Signals
- Next check the voltage
on the Input Power Fail pin with respect to Standby Return. The voltage should be a logic
LO, +0.5V or less. Finally, check the voltage on the Output Power Good pin with respect
to Standby Return. The voltage should be a logic HI, approxi5V. These signals
need pull-up resistors to 5VStandby using 10K Ohm resistors.
