Undervoltage, overvoltage and frequency monitoring in 3(N)AC systems 0…500 V
Various monitoring functions selectable U, f
Asymmetry, phase failure and phase sequence monitoring
Adjustable start-up delay, response delay and delay on release
The multi-functional VMD420 series voltage relay is designed to monitor the frequency, undervoltage and overvoltage and the voltage between two threshold values in 3(N)AC systems. The voltages are measured as r.m.s. values. The currently measured value is continuously shown on the LC display. The measured value required to trigger the alarm relay is stored. Due to adjustable response times, installation-specific characteristics, such as device-specific start-up procedures, short-time voltage fluctuations, etc. can be considered. The devices require an external supply voltage.
Undervoltage, overvoltage and frequency monitoring in 3(N)AC systems 0…500 V
Asymmetry, phase failure and phase sequence monitoring
Different monitoring functions selectable U, f
Start-up delay, response delay, delay on release
Adjustable switching hysteresis
r.m.s. value measurement (AC)
Digital measured value display via multi-functional LC display
Preset function (automatic assignment of basic parameters)