Thermo 4862, Руководство по эксплуатации и техническому обслуживанию

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SECTION 10 - BACKUP TROUBLESHOOTING
(FOR QUALIFIED SERVICE PERSONNEL ONLY)
DANGER! ELECTRIC SHOCK HAZARD
EXISTS DURING MOST TROUBLESHOOTING
PROCEDURES. SERVICE PERSONNEL MUST
USE PROPER SAFETY PRECAUTIONS.
Note: Troubleshooting should be performed using at least par-
tially discharged batteries. A normally functioning charger will
automatically shut down if batteries are fully charged. Batteries
pulled from stock should have a full charge when new.
10.1 CIRCUIT DESCRIPTION
a. When voltage is applied to J1 or J2, relays RL1 and RL2
are energized and connect the batteries to the charger
circuit. Charger chip U2 monitors battery voltage. If
charging is needed, U2 regulates the output of power
transistor Q1 that feeds current into the batteries. Pin 10
of U2 (open collector) is pulled to ground and the charg-
ing LED D3 (see Figure E) is ON.
Note: U1 will be warm to the touch whenever the charger is on.
QI will be warm to the touch when batteries need charging and
yellow charge LED is on.
b. If batteries are fully charged, charger chip U2 will regu-
late Q1 to maintain a float maintenance voltage of about
29.3V to the batteries. Pin 10 of U2 goes high and the
float LED is ON. See Figure E.
Note: Q1 should be cool to the touch when batteries are fully
charged and green float LED is ON.
10.2 CIRCUIT CONDITIONS WHEN CHARGING
Measure battery voltage before starting charge. When
charger is plugged in, an audible click of the relays should be
heard.
a. If operating properly, battery voltage should start to rise
when charger is plugged in. Voltage should rise at a rate
of about 1 volt per hour. Battery voltage may rise quick-
er if batteries are near full capacity. Battery voltage dur-
ing charging may be near 32 volts DC just before charg-
ing cycle is complete.
If the battery voltage doesn't start rising:
1. Check for 12VDC at U1
2. Check for proper resistor values RI-R7
3. Check for blown Q1 or U2.
4. Check for blown fuse (see Figure E)
10.3 CIRCUIT CONDITIONS WHEN IN FLOAT MODE
Charger enters float mode when batteries are fully charged.
Battery voltage should level off to between 29.0 - 75.7VDC at
25°C. Green LED should be ON and battery voltage should
stop rising.
a. If ambient temperature is significantly lower than 25°C,
battery voltage may be slightly higher. Float voltage is
automatically adjusted at -48mv/°C. Float voltage at
15°C may be between 29.5 - 30.3VDC.
b. If ambient temperature is significantly higher than 25°C,
battery voltage may be slightly lower. Float voltage at
37°C may be between 28.4 - 29.2VDC.
If the battery voltage doesn't stop rising or doesn't finally
settle into proper float voltage:
1. Check for proper resistor values R1-R7
2. Check for blown Q1 or U2.
10.4 CIRCUIT CONDITIONS WHEN BATTERY BACKUP
IS IN USE
Relays will de-energize and batteries will connect to J4-4
and J4-5. If main power switch of roller unit is on, batteries
will run motor with voltages up to 24V. Control pot connected
to J3 regulates battery voltage to motor.
If motor doesn't run, check:
1. Control pot turned up
2. Blown U4
3. Wrong or missing R13.
10.5 FUSE REPLACEMENT (SEE FIGURE E)
Locate the fuse holder marked F1 on the battery backup
board. Replace with type below:
1 1/4 X 1/4 3AG 250V, 0.5AF
FACTORY INSTALLED BATTERY BACKUP
CATALOG NUMBER 349017- PARTS LIST
Item No. Description Wheaton P/N
1 SCREW, #6-32 X 1/4" LG., PPHM 052239
2 PCBA, BATTERY BACKUP 052686
3 BRACKET, BATTERY BACKUP 052684
4 BATTERY, 12V, 3.4 AMP 052685
5 WIRE SET, BATTERY BACKUP 052687
Model 4862 Cell Roller_________________________________________________________Battery Backup Troubleshooting
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