Mounting Instructions and Operating Manual for
Fully Automatic Battery Chargers:
Automatic Charger Pb 1240 SMT 3B Charging Capacity 12 V - 12 V / 40 A No. 3124
Automatic Charger Pb 1250 SMT 3B Charging Capacity 12 V - 12 V / 50 A No. 3125
Automatic Charger Pb 1260 SMT 3B Charging Capacity 12 V - 12 V / 60 A No. 3126
Please read the mounting instructions and the operating manual including the safety
instructions attentively.
Particularly observe page 2 "Safety Regulations and Appropriate Application",
prior to starting connection and start-up.
Fully automatic battery charger with 3 charging ports for high-quality motor homes, intervention and
special purpose vehicles, as well as the marine field.
VOTRONIC chargers of series "Pb - SMT" distinguish by their compact design, low weight (high-frequency switching power
supply, Switch Mode Technology), as well as full charging capacity - even in the event of large fluctuations in the power
supply (undervoltage/overvoltage, sine wave form, frequency).
The intelligent microprocessor charging control with charging programs "IU1oU2oU3" (constant current - constant voltage)
and dynamic charging time calculation ensures automatic, quick and gentle full charging, as well as subsequent 100 %
trickle charge of the connected batteries from any charging state. At the same time, simultaneous supply of 12 V consumer
loads, which are connected in parallel, is ensured or charging of very large batteries (depending on case of application).
Charging Ports and Charging Programs:
1. Main Battery "A (Master)", full charging capacity:
Charging programs 1) - 3) for batteries in lead technology "Lead Acid / AGM 1" - "Motor" - "AGM 2" - "Gel"
Charging Program 4) for batteries in LiFePO4-technology "14.4 V"
Automatic lithium trickle charging 5) of the LiFePO4 battery when the vehicle is stopped (seasonal operation) to
maintain a charging state of 50-80 %, which is advantageous for the battery lifetime. Simultaneous floating of 12 V
consumer loads, such as alarm systems, WLAN etc., as well as the vehicle's starter battery. See page 6.
2. Main Battery "B", full charging capacity, with built-in switchable charging current distributor:
a) Battery type "B = A". Parallel charging B with the same charging programs as battery A 1) – 4). See table 3.
b) Starter battery "B < A". The charging program B is designed for the vehicle starter battery for quick starting ability
and trickle charging by additional components, particularly in case of very high consumer current rates.
3. Signalling/Charging Port "C":
Signalling port 12 V for vehicle engine immobilizer, mains display or as separate auxiliary port 12 V /, 4 A, usable for
support charging and trickle charging of a (lead) vehicle starter battery with overcharge protection. See page 3.
Further Characteristics of the Unit:
The charging voltage is free from peaks and is controlled in such a way, that overcharging of the batteries is excluded.
Fully Automatic Continuous Operation: The charger may be connected continuously to the battery, thus keeping the
full charge. Battery discharge in case of power failure is avoided (separation by safety relay).
Charging aid for deeply discharged (lead) batteries or switched-off LiFePO4 batteries: Gentle preliminary charging of
the (lead-acid, gel, AGM) battery or automatic reactivation of the Li battery, in case of possibly switched-on consumers.
Maintenance Lithium LiFePO4, Auto Wake Up, Maintenance Phase: Regular, automatic activation of the battery cell
equalization charging (balancing) every 10 days to ensure continuous full capacity of the battery.
Battery regeneration in case of extended standstill periods: twice a week to avoid harmful acid accumulation.
Parallel and Floating Operation: In case of simultaneous consumption, the battery will either continue to be charged or
maintained via trickle charging. Calculation and control of the adaptation of the charging times is effected automatically
by the charger.
Unattended Charging: Multiple protection against overload, overheating, overvoltage, short circuit, reverse battery,
incorrect behaviour and back discharge of the battery by electronically controlled gradual reduction down to complete
separation of charger and battery by integrated safety relays.
Connection for Battery Temperature Sensor (Temperature Sensor 825, Order No. 2001, is required):
Lead batteries (acid, gel, AGM): In case of low outside temperatures, full charging of the weak battery is improved by