Votronic 1723 MPPT 360 CI Solar Charge Controller 12V 26A 360Wp

The MPPT 360 CI from Votronic (MPN: 1723) is a solar charge controller for 12-V solar systems in motorhomes, travel trailers, marine applications, and stationary off-grid systems. It supports solar modules ranging from 50 to 360 Wp, with a maximum module current of 21 A and a maximum open-circuit voltage (Voc) of 60 V. On the battery side, up to 26 A of charging current is available for the service battery, as well as up to 1.5 A for trickle charging the starter battery. It supports lead-acid, gel, AGM, and LiFePO4 batteries with a total of eight selectable charging programs.

MPPT Solar Charging for RVs, Trailers, and Off-Grid Systems

• MPPT technology for automatically determining the optimal operating point of the connected solar modules
• Designed for 12-V battery systems
• Recommended to maximum solar module power: 50–360 Wp
• Up to 21 A solar module current and a maximum of 60 V Voc
• Maximum 26 A charging current for the living area battery
• Separate charging output with up to 1.5 A for the starter battery
• 3 charging programs for lead-acid, gel, and AGM batteries
• 5 charging programs for LiFePO4 batteries
• Multi-stage IU1oU2 charging curve
• Connection for a battery temperature sensor
• CI-Bus connection for integration into compatible vehicle systems
• Connection options for Votronic solar display units
• Output for EBL solar power display
• AES switching output for compatible refrigerators
• Protection against, among other things, overload, overheating, short circuits, and reverse polarity
• Automatic compensation for voltage drops across the charging cables

MPPT technology for more efficient use of solar power

It operates using the Maximum Power Point Tracking (MPPT) method. The electronics determine the operating point—at which the connected solar modules deliver their maximum possible output—several times per second. Any excess voltage on the module side is converted into additional battery charging current. Compared to conventional control technology, MPPT technology can achieve a charging current gain of approximately 10 to 30%; the specified efficiency is over 95%. This advantage is particularly evident at cool temperatures and under weaker or diffuse lighting conditions. MPPT control thus differs fundamentally from simple PWM control. Instead of essentially matching the module voltage to the battery’s voltage level, the controller converts excess module voltage into usable charging current. This enables better utilization of suitable solar modules.

Two Battery Outputs for the Onboard and Starter Batteries

In addition to the main charging output for the 12-V service battery, the solar controller has an additional output for trickle charging the vehicle’s starter battery. While the service battery can be charged at a maximum of 26 A, up to 1.5 A is available for the starter battery. The manual explicitly describes this second output as a backup and trickle-charging function. This makes it particularly suitable for vehicles in which the solar system primarily charges the service battery, but the state of charge of the starter battery must also be maintained at the same time.

Eight charging programs for lead-acid and LiFePO4 batteries

Eight switchable charging curves are available for different battery technologies. Three programs are designed for lead-acid, gel, and AGM batteries, and five additional programs are for LiFePO4 batteries. These include various voltage profiles as well as a special program for heated LiFePO4 batteries. The multi-stage IU1oU2 charging curve divides the charging process into pre-charge, main charge (bulk), absorption phase, and float charge. This allows the controller to automatically adjust the current and voltage to the battery’s current state of charge.

Temperature-Dependent Battery Charging

It features a connection for an optional Votronic battery temperature sensor. For lead-acid batteries, this allows the charging voltage to be adjusted based on the battery temperature. At low temperatures, the voltage is increased; at high temperatures, it is reduced. For LiFePO4 batteries, temperature monitoring serves primarily to provide protection against both high and low battery temperatures. Important for selection and installation: A temperature sensor is always required when lithium characteristic curves are set. An exception is the special charging program for heated LiFePO4 batteries, for which the manual explicitly specifies a different operating mode. The specific setting must therefore be adjusted to match the battery being used.

CI-Bus, EBL, and Solar Displays

The MPPT 360 CI offers several interfaces for integration into vehicle and monitoring systems. Relevant operating data can be transmitted to a suitable central vehicle display via the CI-Bus connection. Additionally, a measurement output is available for the solar power display of an existing EBL (electrical block). According to the manual, a separately available cable set is required for the EBL connection. Furthermore, the solar charge controller is designed to be plug-and-play for various Votronic display and monitoring solutions.

AES Output for Compatible Refrigerators

Another connection is the AES switching output with 12 V / 0.2 A. AES stands for “Automatic Energy Selector.” In the event of a sustained solar power surplus, the controller can use this output to send a signal to compatible refrigerators to switch from gas to 12-V operation. This output is intended solely as a control signal. For larger loads, a suitable additional switching solution must be used accordingly.

Protection Functions for the Battery and Vehicle Electrical System

The solar charge controller operates fully automatically and features several integrated protection and monitoring functions. These include protection against overload, overheating, short circuits, and reverse polarity, as well as a backflow preventer for nighttime operation. A vehicle electrical system filter supports parallel operation with other charging sources, such as AC chargers or alternators. In addition, the controller automatically compensates for voltage drops in the charging cables. An overvoltage limiter protects sensitive 12-V loads. The permissible ambient temperature range is -20 to +45 °C.

Installation and Applications

Votronic intends the MPPT 360 CI for use in motorhomes, travel trailers, marine applications, and stationary off-grid systems, such as in garden homes or vacation homes. Installation should be on a flat, hard surface protected from moisture, near the vehicle battery. Vertical installation with downward-facing connections is intended. The required cable cross-section is 6–10 mm² on the panel side and 6–10 mm² on the battery side, depending on the cable length. The device-side fuse for the vehicle battery is rated at 30 A.

Technical Specifications

• Battery system: 12 V
• Lead-acid battery nominal voltage: 12 V
• LiFePO4 battery nominal voltage: 12.0–13.3 V
• Solar module power: 50–360 Wp
• Solar module current: 0–21 A
• Max. solar open-circuit voltage (Voc): 60 V
• Max. charging current for the auxiliary battery: 26 A
• Pre-charge current for a deeply discharged battery: max. 13 A at <10 V
• Max. charging current for starter battery: 1.5 A
• Charging programs: 8
• Lead-acid/gel/AGM charging programs: 3
• LiFePO4 charging programs: 5
• Charging method: IU1oU2
• AES switching output: 12 V / 0.2 A
• Self-consumption: 4 mA
• Standby current consumption: 4 mA
• Device fuse for auxiliary battery: 30 A
• Operating temperature range: -20 to +45 °C
• Weight: 285 g
• Dimensions: 131 × 77 × 40 mm
• Certification marks according to the manufacturer: CE, E-mark (EMC/Automotive Directive)

Package Contents

1x Votronic 1723 MPPT 360 CI Solar Charge Controller 12V 26A 360Wp
1x Installation and User Manual