When you connect a device containing a coil, such as a relay or an electromagnetic lock, it is necessary to protect the intercom against voltage peak while switching off the induction load. For this way of protection we recommend a diode 1 A / 200 V (included in the accessories) connected antiparallel (cathode of diode is connected to positive terminal of the power supply and anode of the terminal is connected to the negative terminal) to the device. The diagram below shows how to connect the diode to Maglock (Fail Safe) and Electric Strike (Fail Secure).
ELECTRIC STRIKE
MAGLOCK