UFC 3-535-01
17 November 2005
14-7.1.2.3
The load should warm up at least 5 minutes before taking readings.
14-7.1.2.4 Use the lowest ratio possible on the current transformer without over-
ranging the current input on the power analyzer. Never connect the airfield load directly
to the power analyzer; output voltages on constant current regulators (CCRs) can
exceed 4,500V.
14-7.1.2.5 If REIL lights are connected to the series lighting circuit, this will cause
fluctuation in the VA and watt readings. Manually shut off the REIL lights before taking
readings, then add REIL load. Note that REIL systems require spare capacity in the
CCR to operate properly. Consult the REIL manual for power requirements.
14-7.1.2.6 Measurements will vary with soil and weather conditions. The best days
for taking readings are when the ground is wet.
14-7.1.3
Use a recording voltmeter or take readings during both day and night at
intervals of one hour to obtain an average supply voltage.
14-7.1.4
If the regulator has input voltage taps, select the tap which most nearly
corresponds to the average supply voltage. The output current on each brightness tap
should be within the current limits of FAA AC 150/5345-10 after any necessary supply
voltage correction is made.
14-7.2
In some current regulators with input voltage taps, the output current will
vary in proportion to input voltage changes. In all cases the output current values must
be within the current limits of FAA AC 150/5345-10.
14-7.3
For regulators which have automatic supply voltage correction instead of
input taps, the output current must be within the current limits of FAA AC 150/5345-10.
14-7.4
The following tests are not mandatory, but will help locate the trouble if the
above test indicates improper operation:
14-7.4.1
De-energize and lock out regulator, disconnect the load, short-circuit the
output terminals with jumper, re-energize regulator observing all safety precautions, and
measure the output current with clamp-on ammeter. If measured values are equal to
nameplate values and within the current limits of FAA AC 150/5345-10, the regulator is
operating satisfactorily. Check the load circuit for faults.
14-7.4.2
Connect load cables (after the circuit has been tested for opens and
grounds, as specified in paragraph 14-5, and inspected to ensure all fixtures are
properly lamped) and measure output current and output voltage simultaneously with
the regulator operating on the highest brightness tap. The significance of the readings is
as follows:
14-7.4.2.1 Satisfactory operation is indicated by correct output current and an output
voltage which is slightly higher than the estimated load voltage and does not exceed the
rated output voltage. The measurement of the load voltage must be compared with the
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