Types of Motor Protection

Motor Protection | Six Types of Protection

A. Overload Protection

Prevents overheating by limiting current draw beyond the motor's rating.

• Thermal Overload Relays – Use heat-sensitive elements to detect excessive current.
• Electronic Overload Relays – Provide more precise protection with adjustable settings.

B. Short Circuit Protection

Protects motors from high current faults.

• Circuit Breakers (MCB, MCCB) – Disconnect power when short circuit occurs.
• Fuses – Melt and break the circuit when current exceeds the rating.

C. Phase Protection (Single Phasing & Imbalance)

• Phase Failure Relays – Detect phase loss and trip the circuit.
• Voltage Monitoring Relays – Protect against voltage imbalance or loss.

D. Over/Undervoltage Protection

• Voltage Monitoring Relays – Detect voltage fluctuations and disconnect power.
• Surge Protectors – Absorb transient voltage spikes.

E. Ground Fault Protection

• Earth Leakage Circuit Breakers (ELCBs) – Detects leakage current and trips the circuit.
• Ground Fault Relays – Monitor insulation resistance and trip when a fault occurs.

F. Overtemperature Protection

• PTC Thermistors & RTDs – Measure winding temperature and trigger alarms or shutdown.
• Embedded Thermal Switches – Automatically disconnect when overheating is detected.