The monitoring relay continuously monitors the parameters of the electrical network and automatically turns off the power in case of dangerous deviations. It prevents the failure of household appliances, industrial equipment, and lighting systems due to power surges, phase misalignment, or zero wire breakage. The installation of a monitoring relay is an economically justified safety measure. This device saves expensive equipment and ensures the stability of the power supply.
To understand how a voltage monitoring relay works, it is useful to familiarize yourself with its internal structure. The device is based on an electronic circuit that:
- constantly analyzes incoming voltage;
- compares it with the specified reference values.
The device is powered by a built-in low voltage source, such as 12 V, which ensures its stability and safety. When the circuit detects a dangerous deviation, it sends a signal to the electromagnetic relay. The latter opens the circuit, de-energizing the equipment.
Types and functionality of voltage monitoring relays
Modern models are divided into single-phase (for 220 V networks) and three-phase (380 V). Key features include protection against overvoltage, undervoltage, skew, and phase loss.
Many monitoring relays are equipped with additional options: digital indication of network parameters, programmable switch-on delays (this protects the equipment from frequent restarts) and interfaces for remote monitoring.
Standard mounting is carried out on a 35 mm DIN rail, which simplifies connection to the control panel.
How to choose a control relay
When purchasing, it is necessary to take into account the rated mains voltage (220 V / 380 V), the range of operation settings, the presence of a visual status indication and the enclosure protection class (IP20 for panel, IP54 for industrial premises).
Be guided by the following criteria:
- for household billboards - single-phase voltage monitoring relays with a current of 25-40 A and a range of 170-270 V;
- for industrial equipment - three-phase models with phase skew protection;
- for CNC machines, a relay with precise adjustment and minimal delay.
For responsible consumers, it is important to be able to fine-tune the turn-on time.
Common mistakes during selection and operation
- Purchase of a monitoring relay with an unsuitable voltage range that does not correspond to the actual network parameters.
- Incorrect setting of the power-on delay time. This can lead to frequent triggers in case of short-term interference or, conversely, to an insufficiently rapid shutdown in case of an accident.
- Ignoring the need to control phase misalignment in three-phase networks.
- Installation without taking into account the temperature conditions and the absence of a test check after installation.
Reasons to order from us
The CHIP and DIP online store offers a wide range of voltage monitoring relays with fast and inexpensive delivery from the warehouse. If necessary, we will help you order a device that exactly matches the parameters of your network and the requirements of the protected equipment. You can check the price of delivery in Moscow or in your region of Russia with the manager.
You can receive an order at our office and pick-up point in Yerevan. Delivery of goods is carried out throughout Armenia by courier and Haypost.
Order delivery to Yerevan, Gyumri, Vanadzor and more than 40 cities and towns of Armenia.
Products from the group «Voltage control relay» you can buy wholesale and retail.