4
DBM20A V2.9 software for smart alternators of Euro 6d-Temp
vehicles
In the past, the alternator charged the starter battery as soon as the engine was running. Classic dual
battery systems such as the IBS-DBS or IBS-DBR, also known as VSR, Voltage Sensing Relay, charge
the auxiliary battery easily and reliably during this time.
Voltage-reducing alternators have been installed for several years, which charge normally when the
vehicle is started and reduce the charging voltage to around 13.3V over the travel time. Among other
things, this prevents the battery from being fully charged after a short time. When charging heavily
discharged auxiliary battery, this can lead to them no longer being fully charged. In some vehicles, an
ATO-Type diode can be installed in series to the alternator fuse, which increases the charging voltage
by 0.6V in classic battery systems and guarantees a fully charged starter and auxiliary battery again.
In recent years with various exhaust gas scandals, the vehicle industry has started to use smart
alternators, which only charge when no load is on the engine (downhill, gear change, braking and
sometimes shortly after the vehicle starts) and thus allegedly reduce exhaust emissions. A DC/DC
charging booster is used here, which continuously ensures a good constant charge on the auxiliary
battery.
The new IBS-DBM20A with software V2.9 and additionally installed LinkStartKit or IBS-DBS dual
battery system activates the dynamic Smart Alternator detection. The measurement of various latest
vehicles has shown that some smart alternators can switch between classic, voltage-reduced and smart
alternator charging. The IBS system monitors the alternator and changes from classic to smart charging
and shortens the charging time if possible. A DC/DC charging booster can only charge up to its
maximum charging capacity. The IBS-DBM20A with installed relay charges with the relay while the
alternator fully charges, whereby the full charging capacity of the alternator brings the auxiliary battery
to approx. 80% charge in a short time. The charging booster with the 3 to 4 charging stages (bulk,
absorption, equalize, float) finishes the charge. On long journeys, the DBM20A changes to float charge
mode at the end of charging to avoid an overcharging of the auxiliary battery.
In combination with lithium batteries, the DBM20A limits the start current to approx. 0.2C
Vehicles with a current sensor to ground
For vehicles with a current sensor to earth, the -Pole connection of the auxiliary battery (Aux)
must be connected directly to the -Pole of the starter battery (Main) and not to the chassis of the
vehicle. All additionally installed consumers must be connected directly to the +/- pole of the additional
battery connected. For individual vehicle brands, the presence of the additional battery can be activated
in the system settings.
