12 •
CHARGING PROGRAM D250T
The D250T will charge the service battery in 4 steps - Bulk, Absorption, Float and Pulse. The last step,
Pulse maintenance, means that the D250T monitors state of charge of the service battery, keeping
the battery fully charged without risk of overcharging. During this step, the D250T will also monitor
state of charger of the starter battery set, sending out voltage to each battery separately to equalize
the two 12V batteries – this will significantly extend battery life. Equalization ends when the service
battery needs charging or when the two batteries in the starter battery set have the same voltage.
STEP 1 BULK
Charging with maximum current until approximately 80% battery capacity.
STEP 2 ABSORPTION
Charging with declining current to maximize up to 100% battery capacity.
STEP 3 FLOAT
Maintaining the battery voltage at maximum level by providing a constant voltage charge.
STEP 4 PULSE
Maintaining the battery at 95–100% capacity. The charger monitors the battery voltage and
gives a pulse when necessary to keep the battery fully charged.
4
3
2
1
PULSE
FLOAT
ABSORPTION
BULK
VOLTAGE (V)
CURRENT (A
)
SMARTPASS 120T FAULT INDICATIONS
Each LED indicator lamp works individually and a flashing light is indicating an error according to
description below.
Note that several combinations can be possible if there is more than one errors. For further details
please refer to the manual - see “FUNCTION INDICATIONS” table.
SMARTPASS 120
+OUT
+OUT
+IN
Reason:
Internal temperature too high and/or current too high in
connection between alternator/starter battery and service battery.
Note that both lamps will flash to even if an error only occurs from
one direction.
Recommendation:
Check service/starter battery with a battery
tester, the service/starter battery may be too deeply discharged
and need reconditioning or replacing. This error can also occur if
the loads are too big and it can help to reduce the use of electric
consumers.
Reason:
Internal temperature too high and/or current too high in
connection from service battery to non-critical consumer. This lamp
will also indicate if battery voltage is too low and the battery guard
is activated, this will disconnect power to the non-critical consumers.
Recommendation:
Reduce the use of electrical consumers,
consider moving the D250T and/or SMARTPASS 120T to a cooler
location with better ventilation or charge the battery.
Reason:
Internal temperature too high and/or current too high in
the connection from alternator to non-critical consumer.
Recommendation:
Reduce the use of electrical consumers and
consider moving the D250T and/or SMARTPASS 120T to a cooler
location with better ventilation.
The indication combination below is indicating overheating error
SMARTPASS 120
+OUT
+OUT
+IN
Reason:
Service battery is overheating.
Recommendation:
Check the service battery with a battery
tester and/or check the installation.
