Ericsson BML 161 51/021, Руководство по обслуживанию

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Fuse replacement
To replace the fuse, perform the following steps:
1. Remove the battery sleeve (see Battery Sleeve Removal).
2. Disassemble the charger (see Case disassembly proce-
dure).
3. Remove the Charger Control Board (see Charger Control
Board removal procedure).
4. Remove the Power Supply (see Power Supply removal
procedure).
5. Remove the two screws (item 29) on the power connector
side of the Power Supply.
6. Separate the Power Supply Cover (item 6) from the Power
Supply Case (item 4) exposing the circuit board (item 18)
and fuse F1.
7. Replace fuse with a like item; Bel Fuse Inc., 5TT1 IA
250V UL/CSA.
8. Reassemble charger using steps 1 through 6 in reverse
order.
TROUBLESHOOTING PROCEDURES
Rapid Charger
The first step in trouble shooting the Universal Rapid
Charger is to make a careful visual inspection of the unit for
signs of burning or overheating of components. Also check
for loose connections and cracked components. If there is no
evidence to indicate the location of the failure, the next step
is to troubleshoot by voltage measurements and/or signal
tracing. For this purpose, functional diagrams are provided.
QUICK CHECKS:
•
Check fuse F1
•
Check AC power cord
•
Check commercial power line voltage
•
Check using a known good battery pack
•
Check battery sleeve charging contacts
•
Check battery sleeve connections to connector PCB
•
Check inside connections between connector PCB
and control PCB
•
Inspect for cold solder joints, solder bridges or pat-
tern cuts
CHECKING PROCEDURES
The following procedures will aid in isolating failures
to field/shop replacable assemblies. The procedures do not
attempt to isolate failures to the component level.
FAULT CONDITION l: Charger does not charge, as indi-
cated by CHARGE (Red) indicator not lighting.
1. Check output voltage of the power supply. + l3Vdc 0.5
Vdc at CN2 pin 1.
If the output voltage is out of range, the power supply
assembly is defective and must be replaced.
2. With a known good battery as a load, check the output
yoltage of the Charge Control assembly. Voltage at
CNIOI pin 5 should be 6.l5Vdc to 10.SVdc. If the voltage
is greater than 10.SVdc, there is the possibility the battery
load is not properly connected to the charge control as-
sembly. Check connections between CN102 pin 5 to the
" + " terminal of the charger sleeve, as well as continuity
to the battery charging contact. Similarly check for conti-
nuity between the ground return CN102 pin 5 and the "-"
terminal of the sleeve/battery terminal. Check for dirt on
both charger and battery contacts.
3. Check the supply voltage to the CPU. Voltage atIC103
pin 42 should be + 5 Vdc 0.25 Vdc.
This voltage is the output of the regulator circuit contained
on the Charge Control Assembly, if the voltage is incor-
rect the Charge Control PCB must be replaced.
FAULT CONDITION 2: Charger does not charge, as indi-
cated by the CHARGE (Red) indicator flashing at a slow
rate.
1. If the battery voltage is below 6.l5Vdc, the battery may
be either excessively discharged or contains one or more
shorted cells. Under these conditions the charge control
circuit normally enters a pre-charge mode or trickle
charge. If this condition persists with a known good
battery and there is continuity between the battery and
CNl 01, then a failure in the charge control circuitry is
indicated and the PCB must be replaced.
If the battery load is excessively discharged, the charge
control assembly is operating correctly by supplying the
pre-charge trickle charge to the battery. Under this condi-
tion, if the battery is good, the trickle charge will raise the
battery voltage above 6. l5Vdc in less than 10 minutes.
Once the voltage reaches 6.15Vdc, the charger will auto-
matically switch to the normal rapid charge rate which
will be indicated by the constant CHARGE (Red) indica-
tor.
AE/LZB 119 1643
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