Exide Technologies Section 94.40 - Manual (Page 56)

SERVICING THE AT30
52
SYMPTOM PROBABLE
CAUSE
RECOMMENDED ACTION
Front panel is
dead, but ac
and dc
voltages are
present at
TB1 1. Control
boards are not
connected
2. Defective
Main Control
board A1
3. Defective
wiring
1. Make sure the Gate Driver pc board (A15) is firmly
connected to the Main Control board (A1) via plugs (J17 to
P17). Make sure the two signal harness plugs are firmly
inserted into the
Gate Driver board connectors (J25 and J26).
2. If the AC ON indicator is lit, but the rest of the front panel is
dead, replace the Main Control board (A1).
3. Check the two harness wirings to the
Gate Driver pc board
(A15) connectors (J25 and J26) for signs of insulation
damage, burns, etc. Confirm all wires are securely crimped in
the connector.
Front panel
dies during ac
power failure
and dc
voltage is
present at
TB1 1. Defective
power resistor
R3
2. Defective
wiring
1. Use a dc voltmeter to measure the dc voltage from TB1(-) to
J25 pin #
25 on the Gate Driver pc board (A15). It is normally
12 Vdc when the rated output voltage is at TB1(+) and TB1(-).
If it is not, remove all power from the AT30, and measure the
resistance from TB1(+) to J25 pin #
19 (see the table in
Section 3.6 for the proper resistance value). If the resistance is
not within 10% of the table value, replace R3.
2. Remove the safety shield, and check the wiring to and from
TB1 and the Main Control board (A1) for signs of insulation
damage or burns. Repair any damaged wiring.
Charger
output
voltage too
high, not
controllable 1. Defective
SCR
2. R4 or R14 is
defective, or
wrong value
3. Defective
temperature
compensation
probe (optional)
4. Defective
Main Control
board A1
1. Disconnect the wire harness plug from connector J26 on the
top of the Gate Driver pc board (A15) and restart the AT30. If
you are able to measure output current, one of the SCRs is
defective. Replace the rectifier module(s) (A16) as needed.
2. See page 61 of Section 3.5. Locate R4 and R14 on the
Gate Driver pc board (A15). Remove one end of each resistor
and measure its value with an Ohmmeter. See the table in
Section 3.6 for resistance values. If either resistor is not within
1% of the specified value, replace R4 and/or R14 as needed.
3. Remove one of the probe leads from TB8 and measure its
resistance. At 77° F / 25° C the resistance should be about
10K Ohms. If it is not, replace the probe assembly (A10).
4. If the front panel meter shows more than 110% of rated dc
current, the Main Control board (A1) may be defective. Unplug
the system harness connectors (J25 & J26) from the Gate
Driver pc board (A15). If the output current drops to zero,
replace the Main Control board (A1).