Bosch LW 30 E Manual Del Usario página 17

8.6 Testing the option board
8.6
Disconnect the mains plug
Detach the option board
from the housing cover
and remove it from the unit
Connect the charger to the
mains via the isolating
transformer
Set mains switch to "2"
(back-up mode)
Termi-
nal no-load voltage
approx. 14.4 V DC
no
?
yes
Set mains switch to "0"
Set the test resistor R to
L
max. resistance
Connect the battery clips
to test circuit A in
accordance with the
adjacent circuit diagram
Set mains switch to "I"
Reduce the resistance of
the test resistor R
L
until I = 30 A
L
Termi-
nal no-load voltage
approx. 14.4 V DC
no
?
yes
Set mains switch to "0"
Disconnect the mains plug
Disconnect the battery
Exchange the option board
9
English
Test circuit A
I
L
+
A=
+
R
V=
L
B
-
U < 13 V (discharge if necessary)
B
Set mains switch to "0"
Disconnect the mains plug
Disconnect the battery
Plug in the option board
and screw it tight
8.7
8.7 Testing the regulating transistor V1
8.7
Disconnect the mains plug
Desolder the base and
emitter terminal of the
regulating transistor
U
B
Test the regulating
transistor with a multimeter
or suitable test circuit (see
Table)
Transistor defective ?
no
Set mains switch to "0"
Disconnect the mains plug
Disconnect the battery
Solder on the base and
emitter terminal of the
regulating transistor
8.8
Connection
polarity
B C E
+ –
+ –
– +
– +
+ –
– +
17
yes
Set mains switch to "0"
Disconnect the mains plug
Disconnect the battery
Desolder the collector
terminal of the regulating
transistor
Exchange the regulating
transistor
9
Resistance
Measuring voltage
approx. 2 V
high ( > 1 MΩ)
high ( > 1 MΩ)
low
low
high ( > 1 MΩ)
high ( > 1 MΩ)