BENDER LINETRAXX ® VMD420 Three phase Voltage Frequency Monitor

BENDER LINETRAXX ®  VMD420 Three phase Voltage Frequency Monitor

Product Overview

LINETRAXX ®  VMD420 is a multifunctional voltage frequency monitor launched by BENDER, designed specifically for 3 (N) AC systems. Its core is used to monitor voltage (under voltage, over voltage), frequency (under frequency, over frequency), and phase related parameters (phase sequence, phase loss, asymmetry). The measurement voltage range covers 0... 500 V (L-L)/0... 288 V (L-N), and the frequency range is 15... 460 Hz. It adopts true RMS (AC+DC) measurement method to ensure data accuracy. The product complies with CE, DIN EN 45545-2, and IEC series standards, with high reliability and industrial grade protection performance, suitable for various electrical safety monitoring scenarios.

Core functions and features

Functional category, specific content, key parameters/description

Monitoring function: Voltage monitoring for undervoltage (U<) and overvoltage (U>), with a resolution of 1 V and a preset value of 0.85Un (undervoltage)/1.1Un (overvoltage)

Frequency monitoring under frequency (<f), over frequency (>f), set resolution to 0.1 Hz (10.0... 99.9 Hz)/1 Hz (100... 500 Hz)

Phase monitoring phase sequence (clockwise/counterclockwise), missing phase (identified through asymmetric settings), asymmetric (5... 30% adjustable)

Time setting delay parameters start delay (0... 300 s), response delay (ton1/2:0... 300 s), release delay (toff: 0... 300 s)

Response speed, voltage action time ≤ 140 ms, frequency action time ≤ 335 ms

Display and Storage: Multi functional LC non luminous display screen, real-time display of measured values (0... 500 V)

Storage function operation value memory, first alarm value history record, fault memory (supports on/off/con mode, optional power-off hold)

Security and operational protection features include password protection (0... 999), sealed transparent cover, continuous self-monitoring, and test/reset button

Output configuration includes 2 independent alarm relays (K1/K2), supporting N/C/N/O switching and configurable monitoring types

Technical parameter details

1. Power supply and model information

Model Supply Voltage (Us) Frequency Range Terminal Type Product Number (Art. No.)

VMD420-D-1 AC 16... 72 V/DC 9.6... 94 V 15... 460 Hz screw terminal B93010005

Push in terminal B73010005

VMD420-D-2 AC/DC 70... 300 V 15... 460 Hz screw terminal B93010006

Push in terminal B73010006

2. Key electrical parameters

Insulation performance: rated insulation voltage of 400 V, rated impulse voltage of 4 kV (pollution level III), maximum withstand voltage test of 3.32 kV

Measurement accuracy: Voltage ± 1.5% (50/60 Hz), ± 3% (15... 460 Hz); Frequency ± 0.2% (15... 460 Hz)

Relay parameters: Contact type is conversion contact, 230 V/5 A under AC-13 category, 24 V/1 A under DC-12 category, electrical life of 10000 cycles

Power consumption: ≤ 4 VA

3. Environment and installation parameters

Category specific parameters

Temperature range: -25...+55 ℃; Transportation/Storage: -25...+70 ℃

Protection level: Internal components IP30, terminals IP20

Installation method: rail installation (compliant with IEC 60715) or screw installation (accessory B98060008 required)

Two module design for shell size, 36 mm (width) x 93 mm (height) x 90 mm (depth)

Wiring specifications for screw terminals: rigid 0.2... 4 mm ², flexible 0.2... 2.5 mm ²; Push in terminal: rigid 0.2... 2.5 mm ²

Typical application scenarios

Voltage sensitive equipment monitoring: protecting precision instruments, industrial controllers, etc. from voltage/frequency fluctuations;

Mechanical equipment control: automatically start and stop machinery and equipment according to the set voltage threshold;

Backup/Emergency Power Monitoring: Monitor the voltage and frequency stability of backup power supply systems such as UPS and generators;

Three phase motor protection: prevent motor damage caused by phase loss, open circuit, and asymmetric load;

Transformer protection: Identify asymmetric loads to avoid transformer overload or failure.

Operation and Configuration

Preset function (PrE run): automatically detects the rated system voltage after the first connection, sets the undervoltage/overvoltage/underfrequency/overclocking response values, and displays "AL not SET" when no voltage is detected, which needs to be manually configured;

Key operation: Parameter setting, alarm reset, and self-test functions can be achieved by testing (T), resetting (R), and menu (MENU) keys. Long pressing (>1.5 s) can call advanced functions;

Meaning of indicator lights: When the power light (green ON) is on, it indicates that the power supply is normal, and when the alarm light (yellow AL1/AL2) is on/flashing, it indicates that the corresponding relay has triggered an alarm.

Key issues

Question 1: LINETRAXX ®  What is the core monitoring range and accuracy of VMD420, and which power supply systems is it applicable to?

Answer: The core monitoring range includes voltage (L-L: 0... 500 V, L-N: 0... 288 V), frequency (15... 460 Hz, display range 10... 500 Hz), as well as phase sequence, phase loss, and asymmetry (5... 30% adjustable); The measurement accuracy is ± 1.5% (50/60 Hz)/± 3% (15... 460 Hz) for voltage and ± 0.2% (15... 460 Hz) for frequency. Suitable for 3 (N) AC systems, supporting two power supply versions: VMD420-D-1 (AC 16... 72 V/DC 9.6... 94 V) and VMD420-D-2 (AC/DC 70... 300 V), covering industrial low-voltage power supply scenarios.

Question 2: What are the flexible configuration options for alarm output and delay settings of this device?

Answer: Alarm output configuration: Equipped with 2 independent conversion contact relays (K1/K2), which can be configured to monitor 8 types such as undervoltage, overvoltage, frequency abnormality, phase sequence error, etc. It supports N/C (normally closed) or N/O (normally open) mode switching, and the fault memory can be set as "keep alarm", "automatic reset" or "power-off hold". Delay setting options: Start delay (0... 300 s to avoid false alarms during the startup phase), response delay (ton1/2:0... 300 s to filter short-term fluctuations), release delay (toff: 0... 300 s to ensure system stability and reset), delay setting resolution is 0.1 s/1 s/10 s depending on the interval (0... 10 s/10... 99 s/100... 300 s), suitable for different industrial scenarios.

Question 3: LINETRAXX ®  What are the key precautions for the installation and operation of VMD420?

Answer: Installation precautions: ① The installation method supports rail (IEC 60715) or screw installation (requires accessory B98060008), with a housing size of 36 mm and sufficient heat dissipation space reserved; ② When wiring, attention should be paid to the wire specifications corresponding to the terminal type (screw/push in type), with a stripping length of 8-9 mm (screw terminal)/10 mm (push in type terminal) and a tightening torque of 0.5... 0.6 Nm; ③ Line protection should be equipped with 6A fuses according to IEC 60364-4-43 standard, and dual line fuse protection is required for IT system power supply. Precautions for operation: ① It is recommended to enable the preset function (PrE run) to automatically configure basic parameters when using for the first time. If no voltage is detected, the response value needs to be manually set; ② Password protection is turned off by default, and 0... 999 passwords can be set to prevent accidental operations; ③ Alarm reset requires long pressing the reset button (R>1.5 s). When the fault memory is in "con" mode and the power is turned off, the alarm parameters remain unchanged.