Ericsson 19A704647P1, Руководство по обслуживанию

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ADJUSTMENTS
This power supply has an output voltage level adjustment.
Potentiometer R13 varies the amount of output voltage fed
back into the control loop, thus allowing precise adjustment of
the output voltage level. This level is to be maintained at 13.8
VDC for use with low power base stations.
INSTALLATION
The power supply can be mounted using mounting holes
found in the chassis.
The power supply is designed for operation from either a
121 VAC (P1, P2, P11, and P12), or 242 VAC (P3 and P14)
source. Before connecting the power supply, measure the
source voltage and then connect either the 120V or 240V unit
to match the source voltage. Refer to the Modification Proce-
dures for details.
FUSE REPLACEMENT
To replace a defective fuse, use the following procedure:
1. Place ON/OFF switch in the OFF position.
2. Remove cap from fuse holder and replace fuse with
a similar type and size [4 amp, 250V(121 VAC input),
2.5 amp, 250V (242 VAC input)].
3. Replace cap and change ON/OFF switch to ON
position.
If trouble persists, check with a qualified service person.
TROUBLESHOOTING TABLE
SYMPTOM AREA TO CHECK
FUSE
BLOWS 1) shorted output
2) shorted D1, C1, C2, C3, T1, VR1,
RV1, F1
NO OUTPUT 1) shorted output
2) output properly connected
3) overtemperature shutdown
4) failed Q1, Q2, D1, U1, T1, S2
OUTPUT
VOLTAGE
LOW 1) output overloaded
2) U1 failure
OUTPUT
VOLTAGE
HIGH 1) failed VR1, U1, Q3
2) failed overvoltage protection circuit
POWER SUPPLY VOLTAGE
READING
LOCATION READING
anode D1
C1 plus
cathode D2
OUTPUT 35 Vrms
25 Vdc
30 Vdc
+13.1 TO 14.1 Vdc
APPLICATION
19A704647P12 unit includes mounting feet and omits the
mounting bracket. A mating connector and mating male con-
tacts are provided for the 13 Vdc output connector.
19A704647P14 operates from 242 Vac input. A power cord is
supplied less a power plug (customer to provide).
MODIFICATION PROCEDURES
The modification procedure to change from 120 Volt to 240
Volt operation is described. To change back to 120 Volt,
reverse the procedure. Refer also to the Schematic diagram and
to Figure 2 for an internal view of the power supply.
Insure that ventilation holes in the unit are not ob-
structed when the unit is mounted or in operation.
NOTE
LBI-38751
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