Options
Every motor switch in this series already protects the motor against overload, short-circuit, overheating and loss of a supply phase. This filter only chooses two extras fitted at the factory: an undervoltage release and auxiliary signalling contacts.
Basic — power poles only, from the incoming supply to the motor. There is no undervoltage coil and no extra signalling contacts. Choose this when the large 97 millimetre knob is enough to start and stop the motor by hand.
Undervoltage — an extra coil on terminals marked D1 and D2. If the supply voltage falls too low, the switch disconnects the motor. When voltage returns, the switch stays off until someone turns the knob again. That stops a machine restarting on its own in an explosive atmosphere — for example a conveyor or feeder that must not run unattended.
Auxiliary contacts — two extra contacts that do not carry motor current. Terminals 13 and 14 are normally open: they close when the switch is on, for a controller input, a lamp or a start permit. Terminals 21 and 22 are normally closed. They are rated 1 ampere at 230 volts in a control circuit, for cables of 1 to 2.5 square millimetres.
Both options — the undervoltage release and the auxiliary contacts in one enclosure.
