Somfy TR4 relay box - 230 V

Somfy TR4 relay box for 4 tubular motors

- control box with isolating relay for parallel switching of 4x 230 V motors
- replacement for Somfy RK3 control box with SKU 1810280
- suitable for central and individual control
- mounted in an impact-proof white plastic box
- control current 230 Volt
- nominal load relay 4.5 Amps per motor
- protection degree IP55
- dimensions 110x110x66 mm (wxhxd)
- including 6 grommets

A tubular motor should never be connected in parallel, because the motors never have exactly the same running time. This may be due to differences in motor type or roller shutter height. When one of the motors reaches its end position first, the other motor continues to run and generates an inductive and capacitive voltage in the stationary motor. This voltage can reach up to 1000 volts and causes the switched-off Motor to briefly rotate in the opposite direction. As soon as the microswitch closes again and the motor receives power again, it will again move in its original direction. This so-called pendulum effect keeps repeating, eventually overloading and damaging the limit switches.