LINETRAXX® VMD420

Undervoltage, overvoltage and frequency monitoring in 3(N)AC systems 0…500 V
Various monitoring functions selectable < U, > U, < f, > 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.

Questions? Contact us!

Undervoltage, overvoltage and frequency monitoring in 3(N)AC systems 0…500 V
Various monitoring functions selectable < U, > U, < f, > 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.

Questions? Contact us!

Features

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, > U, < f, > 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)

LEDs: Power On, Alarm 1, Alarm 2
Measured value memory for operating value
Continuous self monitoring
Internal test/reset button
Two separate alarm relays (one changeover contact each)
N/C or N/O operation and fault memory behaviour selectable
Password protection for device setting
Sealable transparent cover
Two-module enclosure (36 mm)
Indication of the system frequency
RoHS-compliant

Applications

Monitoring of voltage-sensitive machines and electrical installations
Switching on and switching off at a certain voltage level
Monitoring of stand-by and emergency supply systems
Supply voltage monitoring of portable loads
Protection of three-phase motors against phase failure and
Transformer protection, asymmetrical load can be recognized