BENDER VMD420-D9-2 Product Description

Overview

BENDER VMD420-D9-2 is a LINETRAXX VMD420 series multifunctional three-phase voltage and frequency monitoring relay manufactured by Bender, VMD420-D9-2 is the complete model designation of this unit. The BENDER VMD420-D9-2 monitors 3(N)AC power systems for overvoltage, undervoltage, overfrequency, underfrequency, phase failure, phase sequence reversal and voltage asymmetry, and sends alarm signals via two programmable relay contacts. This VMD420-D9-2 voltage monitoring relay serves as a reliable Bender LINETRAXX VMD420 series monitoring relay, widely used for generator, motor and low-voltage distribution network supervision in power protection systems of the Bender LINETRAXX VMD420 series monitoring relay.

Features

This BENDER VMD420-D9-2 adopts true RMS measurement technology for accurate reading under distorted waveforms for the Bender LINETRAXX VMD420 series monitoring relay. It is equipped with an LCD display and operating buttons for real-time parameter viewing and threshold configuration. It supports adjustable start delay, response delay and release delay to avoid false alarms caused by transient grid fluctuations. Two independent SPDT relay outputs can be flexibly assigned to different monitoring events. It features alarm history memory, test and reset functions, and password lock for parameter protection. The BENDER VMD420-D9-2 is designed as a 36mm width DIN rail module with transparent protective cover, featuring good EMC performance for long-term stable operation in industrial power cabinets of the VMD420-D9-2 voltage monitoring relay.

Specs

The BENDER VMD420-D9-2 series: three-phase multifunctional voltage and frequency monitoring relay. Measuring range: 0~500V L-L, 0~288V L-N. Monitoring functions: overvoltage, undervoltage, overfrequency, underfrequency, phase loss, phase sequence, voltage asymmetry. Frequency range: 15~460Hz. Output: 2 × SPDT programmable relay contacts. Contact rating: 5A 230VAC. Mounting: DIN rail NS35, 2-module width. Protection rating: IP20. The BENDER VMD420-D9-2 complies with IEC 60255, CE and UL standards as a VMD420-D9-2 voltage monitoring relay.

Principle

BENDER VMD420-D9-2 samples three-phase voltage signals continuously. The BENDER VMD420-D9-2 internal microprocessor calculates RMS voltage, frequency and phase balance degree, and compares the measured values with preset thresholds. When electrical parameters exceed the setting limits, the corresponding relay contact switches to output alarm or trip signal. It can identify reversed phase sequence and missing phase conditions rapidly. The true RMS sampling structure of the Bender LINETRAXX VMD420 series monitoring relay ensures reliable supervision even when the grid waveform is distorted.

Applications

This BENDER VMD420-D9-2 is widely used in generator sets, motor control cabinets, industrial main distribution boards, marine power systems and renewable energy grid connection cabinets. It is applied for early warning and load protection against grid abnormalities. It is used for spare replacement and retrofit of existing Bender power monitoring circuits. The BENDER VMD420-D9-2 delivers dependable multi-parameter grid monitoring for three-phase AC power systems as a proven VMD420-D9-2 voltage monitoring relay.