Overload protection is most frequently mentioned in electrical systems with contractors. It is a safety feature designed to stop or lessen the damage that can result from electrical problems. In most cases, a protective system will immediately turn off the flow of electricity if a problem develops within electrical circuit contractors. Another sort of overload protection, sometimes known as thermal protection, can be used to protect motor systems and other similar equipment in addition to electrical systems.
Many people have experienced blowing a fuse or tripping a circuit breaker in their homes. This happens because of overload protection. Most electrical systems are built with an overload relay or fail-safe device that detects when something is wrong with the circuitry and automatically shuts off electricity to prevent fire or other issues.
Different Types of Overload Protection with Contactors
Bimetal overloads, ambient-compensated overload relays, and electronic overload relays are a few of the several types of overload relays with contactors.
Bimetal Overloads: It makes use of a trip lever made of a bimetal strip. The bimetal strip becomes heated under an overload condition and bends to close the circuit.
Ambient Compensated Overload Relays: These are like bimetal overloads. The primary distinction is that ambient temperature, or the temperature of the surrounding environment, is supported by ambient compensated relays. These relays can avoid false tripping with contractors by allowing the ambient temperature to be greater.
Electronic Overload Relays: These devices’ heaters present in bimetal and ambient-compensated overload relays are absent. By identifying phase losses and severing the motor’s connection to the power source, the electronic overload relays also protect against phase loss. Electronic overload relays come in a variety of types to suit a variety of purposes.
The Functionality of Electronic Overload Relay with Contactors
A motor overload relay’s primary duty is to monitor the current flowing through the motor. A predefined amount of overcurrent is what triggers an electrical overload relay to either send a signal or disconnect the load from the power source.
By cutting off power to the contactors coil, which separates the motor from the power line, the relay is a component of an overall protection system that was installed to safeguard the motor, the branch conductors, and the motor control equipment against sustained overloads. But it doesn’t stop the motor from powering on its own. Through the detection of overcurrent up to about 10 to 12 times the full load motor current, it serves to safeguard the motor, controller, and conductors.
An overload relay should function when there is a persistent current overload. A motor’s insulation is vulnerable because insulation breakdown is caused by motor heating, which rises with the square of the current. The motor’s current temperature rises because of drawing excessive mechanical loads or using low line voltage. Overheating would follow if the overload relay fails to carry out its intended purpose—interrupting the control voltage, which effectively disconnects the motor from the line.
Motor overheating is a result of a three-phase voltage imbalance, which can lead to a current imbalance of up to 15 times the voltage imbalance. The responsibility of overload relays is to keep an eye on and react to these circumstances.
Purchase Electric Contractors from Top-Quality Suppliers
Overload relays can be installed in motor applications to stop motors from operating under overload and can shield your motors from harmful heat. As it is important equipment, one must only purchase good quality products. Finding such a good supplier is not very difficult as you can do online research. To find more information, you can find more information by talking to them using their email id or the phone number available on their website.