Battery-to-battery charger VCC 1212-50 CI - optimal charging even on short journeys
12V to 12V | 50A charging booster | EURO 6 | Lead-acid, Gel, AGM and lithium batteries | IU1oU2 charging curve | 9 charging programs
The new VCC 1212-50 CI is the successor to the proven VCC 1212-50 and introduces a significant further development: the integration of the CI-BUS interface.
As a fully automatic battery charging converter (booster), the VCC 1212-50 CI has been specially developed for mobile use in motorhomes, boats and also special-purpose vehicles. It reliably charges the leisure battery while driving from the alternator via the starter battery.
Unlike a conventional split-charge relay, the battery-to-battery charger specifically adjusts the charging voltage according to the selected charging program – both upwards and downwards. This makes it particularly suitable for vehicles complying with EURO 6 and 6+ standards, where the alternator voltage can fluctuate significantly.
Nine selectable charging programs cover various battery technologies – from conventional lead-acid, Gel and AGM batteries to modern lithium LiFePO4 batteries. They ensure unattended, rapid and gentle full charging from any state of charge, followed by automatic charge maintenance and battery care.
Even on short journeys, the battery is supplied with the full charging current. Connected 12V loads are automatically supplied at the same time – even when the onboard electrical system is heavily loaded. The integrated automatic power control always ensures the required level of safety and maintains the vehicle's ability to start.
General sizing recommendation: To avoid overloading the alternator, it should ideally have twice the rated output of the charging booster. For a 50A charging booster, an alternator rated at a minimum of 100A is therefore recommended.
Features:
- 12V to 12V / 50A
- integrated CI-BUS
- for lead-acid, Gel, AGM and LiFePO4 batteries
- compensates for cable losses and alternator voltage fluctuations
- for vehicles complying with EURO 6 and 6+ standards
- 9 selectable charging programs
- protection of connected 12V loads against overvoltage and voltage fluctuations
- high charging performance even on short journeys
- full charging on longer journeys
- no intervention in the starter circuit
- unattended charging – integrated protection functions
- connection for battery temperature sensor (included in delivery)
- compact design, low weight
What advantage does the CI-BUS offer with the VCC 1212-50 CI?
In an increasing number of caravans and motorhomes, modern CI-BUS onboard management systems provide centralised control of a wide range of devices and functions within the onboard network – a trend reflecting the continuing digitalisation of the recreational vehicle industry. Innovative solutions such as wireless control of heating, air conditioning and other onboard equipment via laptop, tablet or smartphone are increasingly becoming part of everyday travel – providing greater convenience as well as improved energy efficiency.
With its integrated CI-BUS, the VCC 1212-50 CI integrates seamlessly into modern onboard management systems and is therefore ideally equipped for today's and tomorrow's connected onboard technology. Connection to a CI-BUS onboard management system for displaying all relevant data on a central vehicle display is made via the 9-pin plug-in terminal strip and must be integrated into the CI-BUS onboard management system!
The CI-BUS was launched in 2011 under the leadership of the Caravaning Industrie Verband (CIVD) as a common industry standard for the caravan industry. It represents future-oriented technology and flexible solutions and has been continuously developed ever since, providing the foundation for a connected and convenient onboard electrical system of the next generation.
Which charging modes does the VCC 1212-50 CI offer?
The device contains 9 charging programs for different battery types stored in the unit, which can be conveniently selected using the four slide switches. Unless the battery manufacturer specifies otherwise, the appropriate charging program can easily be determined using the operating manual and the technical data – particularly the U1 and U2 voltages. All charging programs automatically take into account possible parallel and buffer operation with connected 12V loads on the leisure battery.
Please always observe the battery manufacturer's charging specifications for all batteries!
Lead batteries (acid, Gel, AGM):
Four specially adapted charging characteristics with corresponding charging voltages and integrated temperature compensation ensure optimal and gentle charging of lead-based batteries.
- Lead Acid: Universal charging characteristic for lead-acid batteries according to DIN 57 510 / VDE 0510 for charging and maintaining the charge of leisure (onboard) batteries. U1=14.40V / 2…6h | U2=13.50V / 24h | U3=13.20V / continuous
- Gel: Adapted to sealed, gas-tight Gel/dryfit VRLA batteries with fixed electrolyte, which generally require longer U1 holding times. U1=14.40V / 6…12h | U2=13.80V / 48h | U3=13.50V / continuous
- AGM 1 14.4V: Adapted to sealed, gas-tight AGM (Absorbent Glass Mat)/lead-fleece VRLA batteries with a specified charging voltage of “14.4V”. U1=14.40V / 1.5…5h | U2=13.50V / 24h | U3=13.20V / continuous
- AGM 2 14.7V: Adapted to sealed, gas-tight AGM (Absorbent Glass Mat)/lead-fleece batteries, Lead Crystal, VRLA with a specified charging voltage of “14.7V or 14.8V” as well as “Lead Crystal” batteries (14.7V). U1=14.7V / 1.5–5h | U2=13.6V / 24h | U3=13.20V / continuous
LiFePO4 batteries:
Five specially adapted charging characteristics with corresponding charging voltages and temperature monitoring ensure optimal and safe charging of modern lithium batteries.
- LiFePO4 13.2V: Adapted for overwintering or storage of a LiFePO4 battery. 13.20V continuously
- LiFePO4 14.4V heated: U1=14.4V / 0.3–1h | U2=13.8V / continuous
- LiFePO4 14.2V: U1=14.20V / 0.5h | U2=13.60V / 24h | U3=13.40V / continuous
- LiFePO4 14.4V: U1=14.40V / 0.3…1h | U2=13.80V / continuous
- LiFePO4 14.2V heated: U1=14.20V / 0.3…0.5h | U2=13.60V / 24h | U3=13.40V / continuous
Warning: Never charge lithium-ion batteries when their temperature is below 0°C. If the battery has an integrated heater, charging is of course possible once the heater powered by the charging current has warmed the battery to above 0°C.
Additional settings and functions of the VCC 1212-50 CI (6 slide switches)
OUT Limit – max. (reduce charging current to the leisure battery):
On the VCC 1212-50 CI, the maximum charging current can be limited using a switch. This allows the charging booster to be adapted to smaller leisure batteries or reduces the load on an existing electrical distribution block, such as an EBL.
In the “max” switch position, the full charging current range from 0A to 50A is available. When the “OUT Limit” current limitation is activated, the maximum charging current is reduced to 39A.
off – Rev. Charge (auxiliary charging branch can only be used with D+ control):
When the leisure battery is charged externally, for example via a mains battery charger, the integrated auxiliary charging output enables automatic support charging and charge maintenance of the vehicle starter battery. For this purpose, part of the available charging current is regulated, monitored and routed to the starter battery. The auxiliary charging output provides a charging current of up to 3A.
This function is particularly useful during extended periods of inactivity or when there is continuous power consumption from the starter battery, for example by vehicle electronics, lighting or audio equipment. The regulated charging process prevents the starter battery from being overcharged.
When the leisure battery has a sufficient state of charge, the starter battery is automatically charged with a charging current of up to 3A. The auxiliary charging branch should remain deactivated if the starter battery is already supplied via a mains charger, solar charge controller or EBL electrical distribution block with a separate charging output.
IN Limit – max (limit current consumption from starter circuit/alternator):
The two switches can be used to limit the maximum current consumption of the charging converter from the starter battery. This is useful if the alternator, plug connections, cables, fuses or other components in the supply circuit have only limited current-carrying capacity.
The current limitation has the greatest effect under high load when the charging converter provides a high charging current and high charging voltage while the input voltage on the starter battery side is low at the same time. This operating condition can occur particularly when the leisure battery is approaching full charge.
Set the operating mode of the charging converter at the starter battery (IN, input side):
The automatic control (activation) of the charging converter after starting the engine can be carried out in two ways:
- For special applications, voltage-controlled via the increased starter battery voltage while the engine is running (not for EURO 6 vehicles!)
- Recommended: via the vehicle's D+ signal (alternator active) or via vehicle terminal 15 when the ignition is switched on.
Option: Parallel connection of two charging converters:
To increase charging performance for large battery banks or high loads (e.g. air-conditioning operation with lower-powered units), two identical devices can also be connected in parallel. Care must be taken to ensure that both devices are connected as symmetrically as possible using the same cable lengths and cable cross-sections to ensure equal power distribution, and that the charging boosters should not load the alternator by more than 50–60%.
Option: Multiple batteries at the charging output:
Parallel charging of two or more batteries with the same voltage (12V) is permitted. For this purpose, the batteries are connected “in parallel” and the capacities (Ah) of the batteries are added together. The total capacity (sum of Ah) should not exceed the specified maximum battery capacity (depending on the application).
Optional accessories for the VCC 1212-50 CI
LED Remote Control S | 2076 | for current charging converters of the VCC-1212 series or LCD Charge Control S | 1248 | compatible with Votronic charging converters of the VCC series
Even when the device is installed in a difficult-to-access location, you can conveniently keep an eye on it at all times. The monitoring and control unit enables convenient remote monitoring and operation, while the LEDs provide a clear overview of the current device status and charging progress. Thanks to the plug-and-play connection, the control unit is easy to install. The integrated switch also enables control of device-specific functions.
Back Contact Relay 60A / 12V | 2202 (for EBL)
When used in conjunction with an electrical distribution block (e.g. Schaudt), installation of this changeover relay is mandatory. It prevents charging current from flowing back from the VCC via the secondary battery into the starter battery. As soon as the engine is running and a D+ signal is present, it disconnects the connection between the starter battery and the electrical distribution block. When the D+ signal disappears after the engine is switched off, the connection is automatically restored.
High-Power Isolation Relay 12V / 140–200A | 2203 | Bypass Relay
Bypass relay that can additionally be used if there is a possibility that a very powerful load consumes more current from the leisure battery than the charging booster can provide, e.g. when operating a living-area air-conditioning system while driving with a high-performance inverter. A special switching output on the VCC activates the bypass relay if the current consumption becomes too high, thereby bypassing the integrated charging booster. When the load current decreases, the relay is switched off and the charging converter resumes controlled full charging of the leisure battery.
Comparison of VCC battery-to-battery chargers
Note: Further technical data for the devices listed in this comparison can be found on the respective product detail page via the “Technical Data” tab or in the respective operating manual via the “Download” tab.
Scope of delivery:
- 1x Votronic battery-to-battery charger VCC 1212-50 CI | 3361 | charging booster
- 1x temperature sensor | 825
- 1x installation and operating manual
- Of course, a German operating manual is also available from us in the download section.
Further helpful tips can be found on our FAQ questions and answers page via the following link FAQ.
