Overload Relays for Motor Protection & Starter Panels

Motor overload relays prevent electric motors from overheating and failure. They monitor the current drawn by the motor and disconnect the control circuit whenever abnormal conditions occur.

At UniGulfSupply, we supply dependable motor protection units for industrial machinery, pump systems, and electrical panels across Oman & UAE. These devices improve equipment reliability and help reduce unexpected shutdowns.

In a control panel, the protection unit works together with a contactor. When excessive current flows due to overload, phase loss, or mechanical jamming, the device trips and stops the motor safely.

Products Included in This Category

This section typically includes:

• Thermal motor protectors

• Electronic motor protection units

• Adjustable current protection devices

• Motor protection modules

• Contactor-mounted protection units

They operate together with Industrial Contactors and controlled by
Industrial Push Buttons.

They also integrate with Motor Starters and are installed inside
Control Panel Components.

Why Motor Protection Is Important

Electric motors draw higher current during overload conditions. Therefore, overheating may damage insulation and winding.

Proper protection helps to:

• prevent motor burnout

• detect mechanical blockage

• identify phase failure

• reduce maintenance costs

• extend equipment lifespan

Additionally, early tripping allows technicians to identify problems quickly before serious damage occurs.

Typical Applications

These devices are commonly used in:

• water pump systems

• compressors

• conveyor drives

• ventilation fans

• HVAC equipment

• industrial machines

• treatment plants

Because motors often operate continuously, reliable protection is essential for safe operation.

How the Protection Works

A simple sequence:

1. Motor starts and draws current

2. Device monitors current level

3. Abnormal current increases temperature internally

4. Control circuit opens

5. Contactor disconnects power

As a result, the motor stops before overheating occurs.

Selecting the Correct Protection Unit

When choosing a unit, consider:

• motor rated current (FLA)

• adjustment range

• compatibility with the contactor

• reset type (manual or automatic)

• surrounding temperature

For example, technicians normally set the current according to the motor nameplate rating.

FAQs

Is this the same as a circuit breaker?
No. A circuit breaker protects wiring from short circuits. Motor protection prevents overheating of the motor itself.

Why is it mounted on a contactor?
Because the device interrupts the control circuit, which then forces the contactor to disconnect power.

Can a motor run without protection?
It can run, however it becomes unsafe and may fail unexpectedly.

Does it switch off main power?
No. Instead, it opens the control circuit and the contactor stops the motor.