Thermal Magnetic Adjustable Double Knob MCCB

A thermal magnetic adjustable double knob MCCB is a moulded case circuit breaker equipped with adjustable thermal and magnetic protection settings.
The double knob design allows users to independently adjust overload protection and short-circuit protection parameters according to different load requirements.
Westhomes thermal magnetic MCCBs provide flexible protection solutions for industrial and commercial low-voltage distribution systems.

The double knob structure provides independent adjustment of:
Thermal overload protection current
Magnetic short-circuit trip current
This allows engineers to accurately match breaker protection settings with actual equipment requirements, improving system reliability and reducing unnecessary tripping.

A thermal magnetic MCCB combines two protection mechanisms:
Thermal protection:
Uses a bimetal element to detect long-term overload conditions and provides delayed tripping.
Magnetic protection:
Uses an electromagnetic mechanism to respond quickly to high fault currents caused by short circuits.
Together, they provide comprehensive protection for electrical circuits.

Depending on the model, adjustable settings may include:
Long-time thermal overload current setting
Instantaneous magnetic trip current setting
These adjustments help optimize coordination between upstream and downstream protection devices.

The main difference is the flexibility of protection settings.
A fixed thermal magnetic MCCB has factory-set trip parameters, while an adjustable MCCB allows users to modify protection values according to actual operating conditions.
Adjustable MCCBs are more suitable for complex industrial applications with changing loads.

Thermal magnetic adjustable MCCBs are commonly used in:
Industrial distribution cabinets
Factory power systems
Motor control centers
Commercial buildings
HVAC systems
Machinery protection applications
They are ideal for applications requiring accurate overload and short-circuit protection.

Yes.
Thermal magnetic adjustable MCCBs are commonly used for motor feeder protection because they can be configured according to motor operating current and startup characteristics.
The adjustable magnetic setting helps prevent unwanted tripping caused by high motor starting currents.

The main difference is the trip unit technology.
Type | Protection Method | Feature
Thermal Magnetic MCCB | Mechanical thermal and magnetic mechanism | Simple, reliable, cost-effective
Electronic MCCB | Electronic sensing and control | Higher accuracy and advanced adjustment
Thermal magnetic MCCBs are widely used for general industrial protection, while electronic MCCBs are preferred for applications requiring precise coordination.

Selection should consider:
Rated load current
System voltage
Short-circuit current level
Required breaking capacity
Load characteristics
Adjustment range requirements
The selected MCCB should provide effective protection without affecting normal equipment operation.

Westhomes thermal magnetic adjustable MCCBs combine reliable protection performance, flexible adjustment capability, and robust mechanical design.
The double knob adjustment structure provides engineers with precise control over overload and short-circuit protection, making them suitable for modern industrial and commercial power distribution systems.