User Manual

Power Cabinet Initial Power Up – continued

July 1999

2-5

SC 4812ET BTS Optimization/ATP – CDMA LMF

PRELIMINARY 2

Power Up Tests

Table 2-3 lists the step–by–step instructions for Power Up Tests.

Table 2-3: Power Up Tests

Step Action

1 Probe the output voltage test point on the DMAC while pressing the 25° C set button on the TCP.

The voltage should read 27.4 +

0.2 VDC. Adjust Master Voltage on DMAC if necessary. Release

the TCP 25° C set button.

2 Depending on the ambient temperature, the voltage reading may now change by up to + 1.5 V

compared to the reading just measured. If it is cooler than 25C, the voltage will be higher, and if

it is warmer than 25C, the voltage will be lower.

3 Close the three (3) Main DC breakers on the Power Cabinet ONLY. Close by holding in the reset

button on the front of the PDA, and engaging one breaker at a time.

4 Measure the voltage between the + and – terminals at the rear of the Power Cabinet and the RF

Cabinet, observing that the polarity is correct. The voltage should be the same as the measurement

in step 2.

5 Place the probes across the black and red battery buss bars in each battery compartment. Place the

probe at the bottom of the buss bars where the cables are connected. The DC voltage should

measure the same as the previous step.

Battery Charge Test

Table 2-4 lists the step–by–step instructions for testing the batteries.

Table 2-4: Battery Charge Test

Step Action

1 Close the battery compartment breakers for connected batteries ONLY. This process should be

completed quickly to avoid individual battery strings with excess charge current

NOTE

If the batteries are sufficiently discharged, the battery circuit breakers may not engage individually

due to the surge current. If this condition is observed, turn off the DMAC power switch, and then

engage all the connected battery circuit breakers, the DMAC power switch should then be turned

on.

2 Using the DC current probe, measure the current in each of the battery string connections to the

buss bars in each battery cabinet. The charge current may initially be high but should quickly

reduce in a few minutes if the batteries have a typical new battery charge level.

3 The current in each string should be approximately equal (+ 5 amps).

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