VMD421H-D-3 Bender Voltage Relay(Multi-functional)

Description

VMD421H-D-3 Bender Voltage Relay(Multi-functional)

Product Dimensions：

Product Description (Detailed Explanation)

The VMD421H-D-3 belongs to the LINETRAXX® series. It serves as a protective device that continuously monitors the quality of the power supply. When voltage or frequency deviates from the user-defined threshold, the device activates its internal relays to trigger alarms or disconnect sensitive equipment.

• Versatility: It is suitable for both AC and DC applications and can handle various system configurations (3AC, 3ACN, DC).

• True RMS Measurement: The device uses True RMS (Root Mean Square) measurement, ensuring accuracy even in the presence of harmonics or distorted waveforms.

• Digital Interface: Features a back-lit LCD screen that displays real-time voltage and frequency values and allows for digital parameter adjustment.

Product Parameters (Technical Specifications)

Product Advantages (Key Benefits)

• Comprehensive Protection: Combines voltage and frequency monitoring in a single, compact unit, reducing the need for multiple relays.

• Fault Memory: The device can be configured to “Latch” (manual reset), ensuring that transient faults are recorded and not missed by maintenance staff.

• High Precision: Digital setting of thresholds and delay times provides significantly higher accuracy than traditional analog potentiometers.

• Self-Monitoring: It features continuous self-testing of the internal electronics to ensure the relay is always functional when needed.

• Password Protection: Settings can be locked to prevent unauthorized changes to the safety parameters.

Precautions (Important Notes)

• Proper Grounding: Ensure the neutral conductor (if used) is correctly wired as per the system type (3ACN) to avoid measurement errors.

• Response Time Settings: Careful consideration must be given to the response delay. Too short a delay may cause “nuisance tripping” during motor starts, while too long a delay may fail to protect sensitive electronics.

• Terminal Torque: Ensure the screw terminals are tightened to the specified torque to prevent overheating or signal loss due to vibration.

• Isolation: Always disconnect the power supply before performing wiring changes to prevent electric shock.

Product Applications (Typical Use Cases)

The VMD421H-D-3 is widely used in power distribution and industrial control:

• Renewable Energy: Monitoring the output of inverters in solar or wind farms to ensure they stay within grid-code voltage and frequency limits.

• Data Centers: Protecting sensitive server racks from “brownouts” (under-voltage) or power surges.

• Emergency Power Systems: Monitoring the stability of backup generators before transferring the load.

• Industrial Motors: Preventing damage to 3-phase motors caused by phase instability or voltage drops.

• Mobile Equipment: Used in cranes or mobile containers where the external power source quality might be unknown.

Shipping Port: Xiamen, China

Payment: Bank of Chicago, Bank of Singapore

Express cooperation: fedex, DHL, UPS and your express account

Service: Professional Sales provides 24 hours /7 days online service

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