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Voltage monitoring relays are crucial for protecting sensitive electronic equipment from fluctuations in power supply. These devices act as a safeguard, preventing damage caused by overvoltage, undervoltage, or phase imbalances. Investing in a reliable relay ensures the longevity and stable operation of your valuable machinery.
Digital display DC voltage detection, control the relay output.
DC 6~80V relay interface board with 2 buttons for easy operation. With clear LED display, convenient to check the value.
Adjustable Voltage Detection Range: DC 0~99.9V.
When the measured voltage is lower than the lower limit or higher than upper limit value, the relay works. Can be used for voltage detection switch, battery over/under voltage protector or discharge meter. Comes with a cover for protection.
True RMS Voltage & Current Monitoring: Features a six LED display for real-time, accurate readings of voltage and current, ensuring precise monitoring of your electrical system
Comprehensive Protection Functions: Provides reliable over-voltage, under-voltage, Phase sequence protection, three-phase unbalance protection，and over-current protection with adjustable trip values and fault recovery delay to safeguard connected...
Fully Adjustable Settings: Customize over-voltage (130V–300V), under-voltage (80V–210V), and over-current (1A–63A) thresholds to match specific application requirements easily
Easy DIN Rail Installation: Designed with a compact form factor for simple and secure mounting on standard 35mm DIN rails, ideal for residential and light industrial use
Energy-Efficient & User-Friendly: Low power consumption (≤2W), long service life, and intuitive operation with reset mode selection make this protector both economical and convenient to use
NOYITO Voltage Relay Module . Voltage detection display range: 0 - 99.9V; Voltage detection error: ±0.1V;
Module working voltage:: DC 10-16V (12V version) DC18-28V (DC24V version) ("Note: The 24V pulse charger may have more than 30V pulse voltage and cannot be used as the power supply for this relay board.").
Module working current: standby average 16mA/12V, relay pull-in 45mA/12V, digital tube off standby current 6mA/12V;
Relay parameters: a set of conversion (normally open normally closed point), contact load: 10A/277VAC 10A/30 DC (NOTE： the maximum DC load 30V 10A) (maximum load current is 1A at 50V DC voltage).
2 INDICATOR LIGHT: Action time of over-voltage relay can be adjusted, 2 sets of normally open and normally closed contacts, 2 indicator lights indicate various working conditions
REAL-TIME MONITOR: The overvoltage undervoltage protector relay is convenient to use, real-time monitoring of dc overvoltage and undervoltage faults
ADJUSTABLE: The overvoltage protector is not additional auxiliary power supply is required. Both over-voltage and under-voltage value can be adjusted
RAIL MOUNT: The voltage monitoring relay made of meterial, with standard modular structure, rail type installation
APPLICATION: The motor overvoltage protector can be used for dc motor, battery, UPS power supply, dc switchgear, dc panel, industrial control system
2 INDICATOR LIGHT: Action time of over-voltage relay can be adjusted, 2 sets of normally open and normally closed contacts, 2 indicator lights indicate various working conditions
ADJUSTABLE: The overvoltage protector is not additional auxiliary power supply is required. Both over-voltage and under-voltage value can be adjusted
REAL-TIME MONITOR: The overvoltage undervoltage protector relay is convenient to use, real-time monitoring of dc overvoltage and undervoltage faults
RAIL MOUNT: The voltage monitoring relay made of meterial, with standard modular structure, rail type installation
APPLICATION: The motor overvoltage protector can be used for dc motor, battery, UPS power supply, dc switchgear, dc panel, industrial control system
REAL-TIME VOLTAGE MONITORING: Continuously monitors DC circuits for overvoltage and undervoltage faults with adjustable voltage thresholds (overvoltage: 13-17V, undervoltage: 10-14V) and action delay time from 0.1 to 15 seconds
DUAL PROTECTION RELAY: Features 2 sets of normally open and normally closed contacts with 6A 250VAC capacity, designed for DC 48V rated voltage applications without requiring additional auxiliary power supply
EASY DIN RAIL INSTALLATION: Standard modular structure with 35mm rail mounting for quick and simple installation, compact dimensions of 3.1 x 0.9 x 3.1 inches and weighs approximately 7.1 ounces
LED STATUS INDICATORS: Equipped with 2 indicator lights that clearly display various working conditions including normal operation and fault action states for easy monitoring
VERSATILE DC APPLICATIONS: Ideal for protecting DC motors, batteries, UPS power supplies, DC switchgear, DC panels, and industrial control systems from voltage fluctuations
IMPORTANT PARAMETERS: ❶Protection function: over voltage, under voltage; ❷Rated voltage: DC 12V/24V/36V/48V; ❸Overvoltage regulation range: 13-17v; ❹Undervoltage adjustment range:10-14v; ❺Contact capacity: 6A 250VAC (resistivity).
REAL-TIME MONITORING: The voltage monitoring relay could achieve real-time monitoring of dc overvoltage and undervoltage faults, and over-voltage, under-voltage value, and action time can be adjusted.
MAIN ADVANTAGE: The voltage monitoring relay is of 2 sets of normally open and normally closed contacts, 2 indicator lights indicate various working conditions, no additional auxiliary power supply is required.
35MM GUIDE RAIL: With 35mm guide rail and standard modular structure, the voltage monitoring relay is easy to install, easy to operate.
TYPICAL APPLICATIONS: The voltage monitoring relay is typically applied in dc motor, battery, UPS power supply, dc switchgear, dc panel, industrial control system.
Last update on 2026-07-15 / Affiliate links / Images from Amazon Product Advertising API
How to Choose the Best Voltage Monitoring Relays
Key Factors When Choosing a Voltage Monitoring Relay
When selecting a voltage monitoring relay, consider the following essential factors to ensure optimal performance and protection for your equipment:
Voltage and Phase Requirements: Determine the operating voltage range your equipment requires. Relays are available for single-phase and three-phase systems. Ensure the relay's specifications match your power supply to prevent incompatibility issues.
Protection Features: Look for relays that offer the specific protections needed for your application. Common features include overvoltage, undervoltage, phase loss, phase reversal, and voltage imbalance detection. Some advanced models may also offer adjustable delay times.
Environmental Conditions and Durability: Consider the environment where the relay will be installed. Some relays are designed for industrial settings and feature robust construction to withstand dust, humidity, and temperature extremes. Check the operating temperature range and ingress protection (IP) rating if necessary.
Frequently Asked Questions
What is the primary function of a voltage monitoring relay?
A voltage monitoring relay's main job is to protect electrical equipment from damage caused by abnormal voltage conditions. It continuously monitors the incoming voltage and disconnects the load if it falls outside a safe, pre-set range.
What is the difference between single-phase and three-phase relays?
Single-phase relays are designed for standard household or light commercial power systems that use two wires (one power and one neutral). Three-phase relays are used in industrial and heavy commercial settings where power is supplied through three alternating currents, offering more stable and efficient power distribution.
How do I determine the correct voltage rating for a monitoring relay?
You need to match the relay's voltage rating to the operating voltage of the equipment it will protect and the power supply it's connected to. Consult your equipment's manual and your electrical panel specifications to find the correct voltage and phase configuration.
Can a voltage monitoring relay protect against power surges?
While some voltage monitoring relays offer overvoltage protection, they are primarily designed to manage steady-state voltage deviations rather than sudden, high-energy power surges. For surge protection, a dedicated surge protector or suppressor is typically recommended in conjunction with a voltage monitoring relay.
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