The undervoltage relay monitors three-phase systems for undervoltage without a separate auxiliary voltage, suitable for installations in accordance with DIN VDE 0100-718 and DIN VDE 0108-100. The standards refer to the erection of lowvoltage installations, in particular for emergency lighting systems and installations for gatherings of people.

Highlights

• Can be used in areas as defined in DIN VDE 100-718 – fixed response value and defined time delay

• Function check using integrated test button

• Simple installation – no separate power supply required

Monitoring of undervoltage without a separate auxiliary voltage

The internal auxiliary voltage is generated from the measurement voltage of all three phases. When errors are detected, the system is switched to the safety power supply.

Permanently set time parameters

The 5TT3 4 undervoltage relays have a permanently set response time that complies with DIN VDE 0100-718 and a defined delay and release time, and are therefore ideal for special applications, such as those in public buildings.