Relay boards

The control system can use up to two relay boards.

Relay boards mounted in the control cabinet. Low voltage to the left, high voltage to the right

The supplier of the relay boards is Conrad electronics:

• Low-voltage relay board 197720
• High-voltage relay board

The Raspberry Pi communicates with the relay board via USB, therefore an additional module needs to be assembled onto each relay board:

• RS232 to USB converter

Experience from longer usage indicates that the high-voltage relay board is not stable leading to a major failure of the control system. The low-voltage relay board only showed minor deviations in device response, there it has been deactivated for the main controls as well.

Both relay boards have been replaced by Controllino.

For future extensions, the control SW still includes the SW parts for operating the relay boards.