Monitoring Relays

As a professional relay manufacturer in China, ATO factory produces high-quality single-phase voltage, 3-phase voltage, DC voltage monitoring relays, and SPDT DIN rail mount phase failure relays. 12V, 24V, 36V, 48V, 110V and 240V rated voltage can be chosen.
With voltage monitoring design, monitoring relays can be widely used in many circuits. ATO has been a supplier for more than ten years in China, we can provide you with wholesale and bulk prices for monitoring relays.

To order a large number of monitoring relays, please contact us now.

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Relays Produced Each Month

Monitoring Relays

A monitoring relay is a protection device for phase and voltage monitoring of power system or equipment. High quality single-phase voltage, 3-phase voltage, DC voltage monitoring relay, and SPDT DIN rail mount phase failure relay are provided by ATO in China. 12V, 24V, 36V, 48V, 110V and 240V rated voltage can be chosen. Monitoring relay with LCD display and keypad afford precise digital setting. Voltage monitoring relay provides reliable relay protection for motors, pumps, fans, cranes, blowers, elevators, power distribution cabinet, air-conditioning system and so on.

Single Phase Monitoring Relay

Single phase voltage monitoring relay is suitable for undervoltage and overvoltage, compact size relay with 1 CO & 1 NC contacts. It can be used in the electric motors and pumps.

3 Phase Voltage Monitoring Relay

3 phase voltage monitoring relay is used to monitor phase loss, phase sequence and voltage unbalance. Overvoltage and undervoltage in the 3-phase power supply of 208-480V AC 50 / 60Hz.

DC Voltage Monitoring Relay

DC voltage monitoring relay is applied in the DC circuit for monitoring undervoltage and overvoltage of DC cabinet and battery. Relay with 2 C/O contacts provide protection for the equipment.

SPDT DIN Rail Mount Phase Failure Relay

DIN rail mount phase failure relay with SPDT (1 C/O) contact, performs the monitoring functions including phase loss and phase sequence in the 3 phase AC power system.

Voltage Monitoring Relay Function:

The under/over voltage monitoring relay is used to automatically disconnect the circuit when the overvoltage and undervoltage in the line exceed the specified value and can automatically detect the line voltage, and it can automatically connect the circuit when the voltage in the line returns to normal, so as to protect our electricity safety.
Voltage monitor relay provided mainly used to protect the insulation of electrical equipment such as generators, transformers, vacuum switches, busbars, and motors from damage by overvoltage. When the power supply line has overvoltage and under voltage, the voltage monitoring relay can quickly and safely cut off the circuit under continuous high-voltage impact to avoid the occurrence of accidents caused by abnormal voltage being sent to the terminal appliances.
When the voltage returns to the normal value, the monitoring relay will automatically connect the circuit within the specified time to ensure that the terminal appliances are in normal operation under unattended duty.

Wide Application

Relays produced by ATO factory are widely used in many fields. The following are the application scenarios in these fields:
1. Monitoring relays can conduct real-time monitoring and analysis of the operating parameters of machines and equipment, and improve production efficiency and safety of enterprise staff.
2. In the automobile industry production line, monitoring relays can monitor and control the production process of various automobile parts, providing quality assurance for automobile parts manufacturing.
3. Monitoring relays can monitor and analyze the operating parameters of various high-voltage electrical equipment in real time to ensure the normal operation and stability of the power system.

Customization

According to customer needs, we can design and provide various types of voltage monitor relays to meet applications with different loads, interfaces, and voltages. Customized relays can improve system reliability and stability, provide convenience for better voltage monitoring, and also improve system safety. We are committed to providing customers with better customized services.

Commitment to innovation is the goal of our supplier's work and the ultimate motivation for our business progress. We have always been strict with ourselves and are determined to be the best in customized services.

How to Test 3 Phase Monitoring Relay

Power-on. Long press "MOD" to enter the parameter setting interface. "RST" is the exit key. Enter "MOD" and press "+" or "-" to modify the value. For the meaning of the parameters, please refer to the instruction manual. Short press "MOD" to display the working times, working time, fault times, and fault time. Press "+" or "-" to display AB, BC, and AC voltage (line voltage).

Phase loss test. When one of the phases is disconnected, the LCDs have a phase loss, the contactor fails to close, and the motor stops. This avoids damage to the motor. When resuming the phase, the LCD shows that the voltage is normal. When "RST" is pressed, the contactor is re-engaged and the motor runs again. (Manual or automatic reset can be adjusted in the parameter settings)

Test the wrong phase protection function. Change the position of L2 and L3. At this time the order is L1, L3, L2. Power on, and the monitoring relay voltage display is normal. At this moment the LCDs "SEQ", indicating the wrong phase. The contactor can’t be closed normally, to achieve the purpose of protecting the motor.

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Monitoring Relays Material

LCD display

With a clear LCD display, the value changes can be timely feedback, convenient to control the working status of the relay.

LED lights

The installation of led helps us to observe the use status of the relay, and can display the working condition of the machine in real time.

Plastic material

Rugged industrial plastic housing reduces external shocks and protects the internal parts of the relay.

Monitoring Relay FAQ

Are monitoring relay programmable?

Monitoring relays are typically not programmable in the traditional sense, as they lack user-defined logic or customizable functions. These devices are designed to monitor specific electrical parameters such as voltage, current, or temperature and activate predefined responses when certain conditions are met. Users can adjust settings like threshold values or time delays, but they don't typically involve extensive programming. Programmable logic controllers (PLCs) or microcontrollers are more suitable for custom logic and automation tasks. However, some advanced monitoring relays may have limited programmability for specific applications, but their primary function remains monitoring and protection in industrial and electrical systems.

What are the different types of monitoring relay?

Monitoring relays are devices that monitor electrical parameters in industrial systems to ensure safe and efficient operation. Various types include:
1. Voltage Monitoring Relays. Detect over/under-voltage conditions to prevent damage or equipment malfunction.
2. Current Monitoring Relays. Monitor current levels to prevent overloads or short circuits.
3. Phase Monitoring Relays. Ensure balanced power distribution by monitoring phase voltages.
4. Temperature Monitoring Relays. Protect against overheating in motors or equipment.
5. Time Delay Relays. Introduce time delays in switching operations, essential for sequencing and control.
6. Frequency Monitoring Relays. Track power supply frequency for stability and consistency.
7. Power Monitoring Relays. Monitor power factors, active/reactive power, and more for efficient energy usage.

What role does monitoring relay play in motor protection?

A voltage monitoring relay plays a critical role in motor protection by continuously monitoring the electrical and operational parameters of a motor. It can detect overcurrent, undercurrent, phase imbalances, and other abnormal conditions. When it identifies a potential issue, such as motor overheating or a fault in the system, it triggers protective actions like shutting off power to prevent damage or injury. This proactive monitoring and response mechanism ensures the motor's safe and efficient operation, extends its lifespan, and minimizes downtime, making it an essential component for safeguarding motors in various industrial and commercial applications.

How does a monitoring relay work?

A voltage monitoring relay is an electrical device designed to monitor specific conditions within an electrical circuit or system. It typically works by continuously measuring one or more electrical parameters, such as voltage, current, temperature, or phase sequence. When these parameters deviate from preset thresholds or conditions, the relay triggers an action, such as opening or closing a circuit, to protect the system or signal an alarm. Monitoring relays are crucial for maintaining safe and efficient operation in industrial processes, ensuring that equipment operates within specified limits, and responding to faults or abnormalities in a timely manner.

How can one configure or set up a monitoring relay?

1. Identify the parameters to monitor, such as voltage, current, or temperature.
2. Set the desired threshold values for these parameters. These thresholds will trigger the relay when exceeded.
3. Connect the monitoring relay to the sensors or devices that measure the parameters you want to monitor.
4. Configure the relay's settings using its interface or control panel to match the threshold values you set.
5. Test the relay to ensure it responds correctly to parameter deviations.
6. Connect the output of the relay to the relevant control or alarm system.
7. Regularly maintain and calibrate the relay to ensure accurate monitoring and timely alerts.

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