Battery Connection Cable for photovoltaic water heaters
- Excess energy use of a battery to heat the water in the photovoltaic boiler.
Battery Connection Cable for photovoltaic water heaters
The battery cable enables the water to be heated by a battery. When the battery is fully charged, the boiler will automatically switch on and convert the energetic surplus into heat. In the first priority, the battery is charged by the photovoltaic modules; as soon as it is full, the surplus is used to heat water.
Product highlights:
- 12V / 24V Battery - Direct connection of 12V and 24V batteries to the boiler.
- 6 modes - Depending on the operating mode of the boiler, the appropriate mode can be set.
- On / Off - The boiler itself recognises when the battery is fully charged. This happens fully automatically.
Recommended system configuration
Each photovoltaic water heater can be charged by 12V or 24V battery. Depending on the volume of the boiler and voltage of the battery, heating times may vary. Below is a chart showing the recommended system configurations.
Recommendation
- The 10 litre boiler can be charged excellently via a 12V or 24V battery system.
- The 30 litre boiler can easily be charged from a 24V battery. If this were heated with a 12V battery, the heating times would be very long.
- The 80 litre boiler can be charged via the 24V battery. However, the relatively long heating times must be taken into account here. Depending on the application and water consumption, this can still be useful.
Connection to the boiler
Installation:
Installation of the battery cable is simple and takes only a few moments. Plug the battery cable into the socket provided on the underside of the boiler. Connect the open ends of the cable directly to the positive and negative terminals of the battery.
Set operating modes on the boiler
Depending on the voltage of the connected battery, the appropriate mode is selected on the photovoltaic boiler. Basically, the mode is selected depending on the battery voltage used. In total, 6 different modes can be selected with each boiler.
Mode 1: Photovoltaic mode (default)
Mode 2 and 3: 12V battery mode
Mode 4: 12V / 24V battery modes when using own energy management system
Mode 5 and 6: 24V battery mode
Below is a detailed list of all modes and their application.
Mode 1
Primary energy source: Solar panel
Secondary power supply: External power supply unit
Standard photovoltaic mode:
The boiler is heated via the directly connected photovoltaic modules.
Optionally, an external power supply unit (can be found in the online shop) can be connected to the boiler for automatic reheating of the water on days with low solar radiation.
Notice:
Mode recommended for the following boiler size: 10l, 30l, 80l
Mode 2
Primary energy source: 12V battery
12V excess energy use
In mode 2, the battery is charged first. As soon as it is fully charged, the photovoltaic boiler uses the surplus energy to heat the water. The boiler switches on automatically when the battery voltage reaches 13.5V and stops heating when the voltage drops below 13.5V.
Notice:
Mode recommended for the following boiler size: 10l
Maximum heating power of the boiler: 79W
Approved battery types: LiFePO4, lead acid
Mode 3
Primary energy source: 12V battery
12V reheating from the battery
In mode 3, the boiler can be reheated via the battery. In this case, the battery is discharged.
If the temperature of the water falls below a minimum water temperature set on the boiler (e.g. 30°C), the boiler uses the energy from the battery to heat up the water.
However, the battery is only discharged to a residual capacity of 50% to ensure that other electrical consumers such as lamps or a refrigerator continue to be supplied with sufficient power. The boiler stops the reheating process when a battery voltage of 12.4V is reached.
If, on the other hand, the water temperature in the boiler is higher than the set minimum water temperature, the battery is not discharged. In this case, the boiler would act as in mode 2 and only start the heating process when the boiler is fully charged.
Notice:
Mode recommended for the following boiler size: 10l
Maximum heating power of the boiler: 79W
Approved battery types: LiFePO4
Mode 4
Primary energy source: External energy management
Energy management system
Mode 4 can be selected if the battery connected to the boiler has energy management. In this mode, the boiler is always activated and uses all the energy provided by the energy management system.
Example:
The energy management of the battery activates an electrical output from a state of charge of 80%. As soon as the electrical output is activated, the boiler uses all the energy until the electrical output is switched off again via the energy management system.
Notice:
The nominal voltage of the battery should be 12V or 24V..
Maximum heating power with 12V batteries: 79W
Mode recommended with 12V: 10l
Maximum heating power with 24V batteries: 316W
Mode recommended at 24V: 30l
Mode 5
Primary energy source: 24V battery
24V excess energy use
In mode 5, the battery is charged first. As soon as it is fully charged, the photovoltaic boiler uses the surplus energy to heat the water. The boiler switches on automatically when the battery voltage reaches 27.0V and stops heating when the voltage drops below 27.0V.
Notice:
Mode recommended for the following boiler sizes: 10l, 30l, 80l
Maximum heating power of the boiler: 316W
Approved battery types: LiFePO4, lead acid
Mode 6
Primary energy source: 24V battery
24V reheating from the battery
In mode 6, the boiler can be reheated via the battery. In this case, the battery is discharged.
If the temperature of the water falls below a minimum water temperature set on the boiler (e.g. 30°C), the boiler uses the energy from the battery to heat up the water.
However, the battery is only discharged to a residual capacity of 50% to ensure that other electrical consumers such as lamps or a refrigerator continue to be supplied with sufficient power. The boiler stops the reheating process when a battery voltage of 24.8V is reached.
If, on the other hand, the water temperature in the boiler is higher than the set minimum water temperature, the battery is not discharged. In this case, the boiler would act as in mode 5 and only start the heating process when the boiler is fully charged.
Notice:
Mode recommended for the following boiler sizes: 10l, 30l
Maximum heating power of the boiler: 316W
Approved battery types: LiFePO4
Scope of delivery
– 1x Battery Connection Cable
– 1x User Manual
