- Prodotti
- Relè di misura e controllo

LINETRAXX® VMD420
The multi-functional voltage relays of the VMD420 series are designed to monitor the frequency, undervoltage and overvoltage and the voltage between two threshold values (window discriminator function) 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 leading to the activation of the alarm relays will be stored. Due to adjustable response times, installation-specific characteristics, such as device-specific start-up procedures, short-time voltage fluctuations, etc. can be considered . Device version VMD420 requires an external supply voltage.
- Features
- Applications
- Accessories
- Ordering information
- Downloads
- 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
- 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
Optional accessories for LINETRAXX® VMD420
Type | Art No. |
---|---|
Mounting clip for screw fixing (1 piece per device) | B98060008 |
Variants of LINETRAXX® VMD420
Type | Supply voltage US* | Nominal system voltage Un* | Art. No.** |
---|---|---|---|
VMD420-D-1 | AC 16…72 V / DC 9,6…94 V, 15…460 Hz | 3(N)AC 0…500 V / 288 V 15…460 Hz | B73010005 B93010005 |
VMD420-D-2 | AC/DC 70…300 V, 15…460 Hz | 3(N)AC 0…500 V / 288 V, 15…460 Hz | B73010006 B93010006 |
* absolute values
**(B7… = push-wire terminal / B9… = screw-type terminal)
**(B7… = push-wire terminal / B9… = screw-type terminal)
Downloads for LINETRAXX® VMD420
Category | Prodotto | Language | Size | Download |
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