Guess you need - in addition to the pressure sensor - also a "Schaltgerät" https://www.mayser.com/de/sicherheitste ... altgeraete which provide a safety contact which cuts the power supply for the motor. These devices have a "Meldeausgang", a potential free contact which can be evaluated by a RPi.
For running the shutter up, down you need two relay. Depends on how the switch is connected you will need possibly a 'dual pole' relay.
Might be more complicated when you want to have a 'manual override' available. If shutter is for a freezer cell, I would prefer to have a manual override inside the box.... and an axe.
Controlling relay is simple, but you need a rule compliant setup (VDE). I would provide a DIN rail-compatible device which is controlled via a field bus. Modbus controllable devices are e.g. https://www.waveshare.com/wiki/Modbus_RTU_Relay_(D) available in many flavors. From the RPi, use an isolated modbus adapter. Or look to the wago environment https://www.wago.com/de/c/io-systeme .
For running the shutter up, down you need two relay. Depends on how the switch is connected you will need possibly a 'dual pole' relay.
Might be more complicated when you want to have a 'manual override' available. If shutter is for a freezer cell, I would prefer to have a manual override inside the box.... and an axe.
Controlling relay is simple, but you need a rule compliant setup (VDE). I would provide a DIN rail-compatible device which is controlled via a field bus. Modbus controllable devices are e.g. https://www.waveshare.com/wiki/Modbus_RTU_Relay_(D) available in many flavors. From the RPi, use an isolated modbus adapter. Or look to the wago environment https://www.wago.com/de/c/io-systeme .
Statistics: Posted by ghp — Wed Jul 09, 2025 2:06 pm