RL421  Slim

RL421 Slim is a universal electronic step relay with semiconductor switching device.


Command from one or more points by means of normally open pushbuttons of any civil series, also with indicator light (max 4 mA total).


The installation does not require direct connection to the neutral wire. The output to the load is 230V.


The device is inserted in a plastic casing and immersed in UL94 V-0 flame retardant polyurethane resin.


This in addition to giving the product fireproof properties, ensures maximum silence in operation.

The product is sold with an instruction sheet.

Self-consumption: None 

                                Instruction sheet

Available on

Technical features

Power supply: 230 Vac 50 Hz

Operating temperature: -5 to 35 ° C 

No delay between command and switching

Status memory: YES (memory in the absence of mains voltage)

  • Does it work with LED lamps?

    Yes, just check that the minimum and maximum loads are respected

  • Once the wires are connected, the lamp stays on

    RL421 only works by connecting the button to neutral.

    If by mistake the push button is connected to the phase, it will still be possible to switch on the lamp at the first pulse, it will then remain blocked in this state.

    Another possibility is to have caused a short circuit as a result of incorrect connections; in this case the lamp is switched on as soon as the voltage is restored.

    The semiconductor inside the relay will be irreparably damaged.