Danfoss 101N0400 Electronic Unit User Manual

Quick guide from the manual

The Danfoss 101N0400 electronic unit is designed for solar applications with BD35F and BD35K compressors. It operates within a voltage range of 10 to 45V DC. Key installation requirements include connecting the terminal plug to the compressor, installing a 15A fuse on the positive cable, and using a main switch rated for at least 20A. The unit features built-in thermal protection and supports optional fan and LED connections.

Installation and Power Supply

Installation: Connect the terminal plug from the electronic unit to the compressor terminal. Mount the electronic unit on the compressor by snapping the cover over the screw head.

Power Supply: The unit must be connected directly to the solar panel poles. Ensure the plus (+) and minus (-) connections are correct, as the unit will not function otherwise. The unit is protected against reverse battery connection.

• Fuse: A 15A fuse must be mounted in the positive cable as close to the solar panel as possible.
• Main Switch: If used, the main switch must be rated for a current of at least 20A.
• Wire Dimensions: Observe the wire dimension requirements provided in the manual based on the length between the battery and the electronic unit.

Thermostat and Speed Control

The thermostat is connected between terminals C and T. When connected directly to terminal C, the unit adjusts speed to the cooling demand.

Fixed Speed Adjustment: Other fixed compressor speeds (between 2,000 and 3,500 rpm) can be obtained by installing a resistor (R1) to adjust the control circuit current. Refer to the compressor speed table in the manual for specific resistor values.

Optional Connections

• Fan: A fan can be connected between terminals + and F. The output voltage between these terminals equals the supply voltage, so the fan must be compatible with the solar panel voltage range.
• LED: A 10mA LED can be connected between terminals + and D to indicate operational errors via flash codes.

Troubleshooting

If the electronic unit records an operational error, the optional LED will flash a specific number of times. The sequence repeats every 4 seconds.

• 5 Flashes: Thermal cut-out of electronic unit (system overloaded or ambient temperature too high).
• 4 Flashes: Minimum motor speed error (system overloaded, motor cannot maintain 1,850 rpm).
• 3 Flashes: Motor start error (rotor blocked or differential pressure > 5 bar).
• 2 Flashes: Fan over-current cut-out (fan load exceeds 1A peak).