Silent solid-state relay, also suitable for ESL and LED lamps. Switch-off warning and permanent light function can be activated. The standby loss is only 0.4 watts. With ESL optimization and multifunctionality. The switching occurs at zero crossing to protect the lamps, which particularly extends the lifespan of energy-saving lamps. Additionally, it features galvanically isolated universal control voltage from 8 to 230 V. It is suitable for 3- and 4-wire circuits, can be connected in series, and provides attic lighting for 4-wire circuits. Automatic detection of the circuit type is also included. The glow lamp current is up to 50 mA, depending on the ignition voltage of the glow lamps. A precise time setting from 1 to 30 minutes is possible with a minute scale. The permanent light switch is operated with a large rotary switch. After a power failure in the function setting TLZ, the lighting will be turned back on, provided the time duration has not yet expired. There are double connections for the switch and lamp, allowing for connection either at the top and bottom or only at the bottom, with the switch-off warning activated.