Buderus FM443 Solar Module Wiring Diagram

Switch Modes

Solar Loop 1 Buffer Bypass (PB)

1* PB: Bypass

2* PB: Buffer

Solar Loop 2 Solar Loop Selection

Module - Front View

The front view of the FM 443 module shows controls and indicators. It includes settings for 'max' temperature, an 'AUT' mode selector with positions 0, 1, and 2, and other indicators.

FM443 Solar Module Wiring Diagram

Power Supply and Internal Connections

The FM443 solar module receives power via terminals L (Live), N (Neutral), and [ground symbol]. Internally, the module features an 'internal BUS' for controller communication. An asterisk (*) denotes inputs designated for automatic control.

Module Inputs and Outputs

The module connects to external components via terminal blocks including PSS 1 (terminals 61, 63), SPB (terminals 41, 43, 44), PS 2 (terminals 61, 63), PSS 2 (terminals 73, 74, 75), and SU. Connections for PSS 1, SPB, PS 2, and PSS 2 utilize AWG14 wire with a maximum current rating of 5A*. The SU terminal also uses AWG14 wire with a maximum current rating of 5A.

Connected Components

Pumps: Solar system pump 1 (PSS1), Solar loop 2 secondary pump (PS 2), and Solar system pump 2 (PSS2) are connected.

Valves: A 3-way switching valve for the buffer bypass loop (SPB) and a 3-way mixing valve for tank 1/tank 2 (SU) are connected.

Sensors: Temperature sensors are connected for the buffer bypass circuit (FPB), heat meters (FR for return, FV for supply), solar tank 2 bottom (FSS 2), solar tank 1 bottom (FSS), and collector (FSK). A flow meter (ZV) is also connected. Connections for these sensors and actuators are made using AWG18 wire where indicated.

Control Voltage and Notes

The control voltage is 120V AC (~). An indicator for 'Extra-low voltage' is present. A critical note states that the total current for the control circuits cannot exceed 10A.