Best Voltage Monitoring Relays of 2026

Harvey Wall Avatar
Harvey Wall
Last Updated: 2 Feb 2026

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Voltage monitoring relays are electronic devices that help protect electrical systems from damage caused by over or under voltage. They are designed to detect changes in voltage levels and trigger an alarm or switch off the power supply when the voltage exceeds or falls below a certain threshold. Voltage monitoring relays are commonly used in industrial and commercial settings to ensure the safe and efficient operation of machinery and equipment. They can help prevent costly downtime, equipment damage and even fire hazards. If you are looking for a reliable way to monitor voltage levels and protect your electrical systems, voltage monitoring relays are an excellent choice.

At a Glance: Our Top Picks

GRV8-02 Voltage Monitoring Relay for Protection Cover #TOP 1
GRV8-02 Voltage Monitoring Relay for Protection
ftb score rating icon 9.8
Programmable Voltage Monitor A30-U1 Relay Controller Cover #TOP 2
Programmable Voltage Monitor A30-U1 Relay Controller
ftb score rating icon 9.7
GAEYAELE Adjustable Voltage Protection Relay Cover #TOP 3
GAEYAELE Adjustable Voltage Protection Relay
ftb score rating icon 9.5

Top 9 Voltage Monitoring Relays

#TOP 1

GRV8-02 Voltage Monitoring Relay for Protection

Keenso39fd85gxq0-01
White
GRV8-02 Voltage Monitoring Relay for Protection Cover
Keenso GRV8-02 Monitor Relay,Single Phase Voltage Monitoring Relay Over Voltage AC/DC Voltage Monitoring for Phase Sequence Protector (GRV8-02/A220) relay

The GRV8-02 Voltage Relay is designed to monitor both AC and DC voltage accurately, ensuring your equipment remains protected from over-voltage situations. Its compact size makes it ideal for installation in tight spaces, while the LED indicator provides a clear visual of its operating status. You can easily select the operating mode using the rotary knob, adding convenience to your control processes. This relay is particularly useful for applications such as compressor protection and motor control, offering peace of mind in your electrical systems.

What We Like
High accuracy voltage measurement
Compact and easy to install
Convenient rotary knob operation
LED status indicator
Versatile application for protection
#TOP 2

Programmable Voltage Monitor A30-U1 Relay Controller

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Programmable Voltage Monitor A30-U1 Relay Controller Cover
Voltage Monitor Module, A30-U1 DC 0-99.9V Programmable Delay Relay Controller Board for Voltage Detection Overvoltage Undervoltage Control

The DONGKER A30-U1 Monitor offers flexible settings for upper and lower voltage limits, allowing you to tailor detection parameters to your needs. With its capability to perform voltage detection, it ensures you are alerted to any overvoltage or undervoltage situations, helping to protect your devices. This device covers a wide voltage monitoring range from 0.1V to 99.9V, providing versatility for various applications. Additionally, it features separated measured and working voltage, enhancing safety and accuracy in your monitoring tasks.

What We Like
Flexible limit voltage settings
Wide monitoring range
Overvoltage and undervoltage control
Separated measured and working voltage
#TOP 3

GAEYAELE Adjustable Voltage Protection Relay

GRV8-01
AC/DC110V-240V
GAEYAELE Adjustable Voltage Protection Relay Cover
GAEYAELE Single Phase Voltage Relay AC/DC110V~240V Adjustable Over or Under Voltage Protection Monitor Relay with LED Display(GRV8-01,AC/DC110V~240V)

The GAEYAELE Voltage Relay offers essential features for monitoring your operating circuit voltage accurately. It utilises True RMS technology, ensuring precise voltage measurements that can help you maintain safe electrical conditions. With adjustable over or under voltage trip settings, you can easily set the desired thresholds for protection. LED indicators provide clear status updates, allowing you to quickly assess the relay's performance at a glance. This compact device is designed for easy din rail mounting, making installation straightforward and convenient.

What We Like
Accurate voltage monitoring
Adjustable trip settings
Clear LED indicators
Compact size
Easy installation
#TOP 4

Walfront AC230V 63A Voltage Current Protector

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Walfront AC230V 63A Voltage Current Protector Cover
Voltage Current Protector Over/Under Voltage Protector AC230V 63A Double LED Display Single Phase DIN Rail Installation

The Walfront Voltage Current Protector is an essential device for safeguarding your electrical systems. It offers over and under voltage protection, ensuring that your equipment remains safe from voltage fluctuations. The double LED display allows you to easily monitor both voltage and current, providing you with real-time insights into your electrical usage. Additionally, the adjustable settings enable you to customise the overvoltage and undervoltage values, along with overcurrent protection and fault recovery delay, allowing for tailored protection that suits your specific needs.

What We Like
Effective voltage protection
Easy-to-read LED display
Adjustable settings for customisation
Low power consumption
Long mechanical life
#TOP 5

DEWIN GRV8-03 Voltage Monitoring Relay

IRCIEIAEA-GS109195-01
One Color
One Size
DEWIN GRV8-03 Voltage Monitoring Relay Cover
DEWIN Voltage Monitoring Relay, Phase Monitoring Relays GRV8-03 M460 Voltage Monitoring Relay Phase Sequence and Phase Failure Protection Relay

The DEWIN Voltage Relay is designed to monitor its working voltage efficiently, providing both phase sequence and phase failure protection. With eight adjustable rated voltages, it can adapt to various electrical systems around the globe, ensuring versatility for users. The relay's operating status is easily visible through its LED indicators, with a green light for power and a red light for output status. Its ultra-small size allows for convenient installation on a 35mm DIN rail, making it ideal for various applications.

What We Like
Effective voltage monitoring
Adjustable for global use
LED status indicators
Compact and easy to install
Prevents equipment reverse operation
#TOP 6

VIFERR DVRD-12 DC Voltage Monitor Relay

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VIFERR DVRD-12 DC Voltage Monitor Relay Cover
VIFERR DVRD-12 DC Voltage Monitor Monitoring Relay DC 12V 24V 36V 48V Over Voltage and Under Voltages Protection Relay (DC12V)

The VIFERR DVRD-12 Relay is a versatile voltage monitoring device designed for various applications, including DC motors and batteries. You can easily adjust the action time and set under voltage values between 10-14V and over voltage values between 13-17V. This ensures your equipment operates safely and efficiently. Furthermore, it monitors DC overvoltage and undervoltage faults in real-time without needing an additional power supply, providing peace of mind. Installation is straightforward due to its standard modular design for rail mounting.

What We Like
Real-time voltage monitoring
Adjustable voltage settings
Easy installation
No extra power supply needed
#TOP 7

YALIDA DC Voltage Monitoring Relay with Timer

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YALIDA DC Voltage Monitoring Relay with Timer Cover
YALIDA DC 6~80V Voltage Monitoring Relay Time Delay Relay Charging Discharge Controller Module Undervoltage Overvoltage Protection Relay with 4 Operating Modes Voltage Control Timer, Blue

The YALIDA Voltage Relay operates within a DC range of 6 to 80V and can handle a contact load of up to 30A. This high-quality monitoring relay features four operating modes, allowing you to tailor its functionality to your specific needs. With adjustable delay times from 0 to 999 seconds, you can easily manage when the relay activates or deactivates. Additionally, it includes a voltage detection channel, which helps you monitor and control voltage levels effectively, ensuring reliable performance in various applications.

What We Like
High-quality and durable design
Multiple operating modes available
Adjustable delay times
Efficient voltage monitoring
#TOP 8

Jadeshay Voltage Protector and Tester Device

LTOTXYYLL-GS109787-02
One Color
100A
Jadeshay Voltage Protector and Tester Device Cover
Jadeshay Voltage Protector Stabilizer,100A 3 Phase Din Rail Voltmeter Ammeter Adjustable Surge Protector Relay for Overvoltage Undervoltage and Overcurrent Protection,with LED Display and Indicators

The Jadeshay Voltage Protector offers essential protection for your electrical systems. It immediately cuts off power during overvoltage, undervoltage, or overcurrent situations, safeguarding your equipment. The device monitors three-phase systems, ensuring safety against phase sequence errors and asymmetries. With a clear LCD display, you can easily check voltage and current statuses at a glance, providing reassurance and convenience. Its straightforward installation on a DIN rail makes setup quick and hassle-free, allowing you to focus on other tasks.

What We Like
Immediate power cut-off
Real-time voltage monitoring
Easy DIN rail installation
Flame-retardant shell
Compact and practical design
#TOP 9

DEWIN 3 Phase Voltage Current Protector

IXRAQCCYR-GS109787-01
One Color
One Size
DEWIN 3 Phase Voltage Current Protector Cover
DEWIN Voltage Protector, 3 Phase Din Rail Voltmeter Ammeter AC220V 63A Over Under Voltage Current Limit Relay Protector

The DEWIN Voltage Protector offers reliable protection for your three-phase electrical systems. It automatically cuts off power during overvoltage, undervoltage, or overcurrent situations, safeguarding your equipment without requiring manual reset. The clear LCD display allows you to monitor voltage and current status in real time, making it easier to keep track of your system’s health. Additionally, its durable, flame-retardant PC casing ensures safety and longevity, giving you peace of mind with low power consumption and excellent insulation.

What We Like
Automatic power cut-off
Clear LCD voltage display
Durable flame-retardant casing
Self-resetting protection
Buying Guide Image

Frequently Asked Questions (FAQs)

1. What are monitoring relays?

A Monitoring Relay is a protective control device. ... Monitoring Relays monitor power supplies (voltage, current, power, phase), temperatures, and other analog signals and detects abnormalities in machines and equipment by determining values against alarm thresholds.

2. What is a voltage monitoring device?

Voltage monitoring devices provide under-voltage as well as Over voltage protection. Also, it protects against voltage related issues like Phase loss, phase sequence and phase asymmetry, Neutral open, over frequency and under frequency.

3. What is 3 phase monitoring relay?

Three Phase Monitoring Relays or Protective Relays, protect motors and equipment from expensive damage due to voltage faults on three-phase systems.

4. What does a phase monitoring relay do?

The devices provide protection against phase loss, phase reversal, and phase unbalance due to blown fuses, broken wires or worn contacts. They monitor simultaneous voltage drops/increases and help to prevent damaged machinery and the injury of personnel.

Editor's Notes

During our voltage monitoring relay research, we found 46 voltage monitoring relay products and shortlisted 9 quality products. We collected and analyzed 3,462 customer reviews through our big data system to write the voltage monitoring relays list. We found that most customers choose voltage monitoring relays with an average price of £20.29.

The voltage monitoring relays are available for purchase. We have researched hundreds of brands and picked the top brands of voltage monitoring relays, including Keenso, DONGKER, GAEYAELE, Walfront, DEWIN.

Written by
Harvey Wall Avatar

Harvey Wall was born and raised in Norwich. He mastered the art of tool production and finished at the prestigious Norwich University. His area of interest include cutting tools, abrasive finishing and power tools. Harvey is always looking for ways to improve the finesse of industrial tools via his myriads of researches. He also shares some of his experiences on many platforms while writing on tool products.