Mains field relays switch off a circuit when the last consumer connected to it has been switched off. As soon as the first consumer is switched on, they switch the mains voltage back on. This protects against the possible health effects of electric magnetic fields. The switch-on threshold of the FSE 1 is adjustable. This means that 'blind consumers' can be hidden and the mains field relay can be prevented from being switched on continuously. The FSE 1 switches off at around 2/3 of the switch-on power. Properties: adjustable switch-on power from 2 VA to 15 VA, rotary switch for automatic and continuous on operation, front LED as switching status display, low power consumption, robust normally open relay, 230 V / 16 A, module width only 1 division unit (17.5 mm), protection class IP 20, mounting type: quick attachment to mounting rail, installation position as desired, areas of application: the use of the mains field relay is recommended wherever electrical interference fields are undesirable or power losses due to standby functions are to be avoided. In particular, these are private and commercial buildings with consumers that are not used for long periods of time (lighting, audio/video components, machines, etc.).