A circuit allows the electrical current to pass through. The current flows from higher voltages to lower voltages. A simple electrical circuit connects a power source, the grid or a battery, and an end device, electronics, or electrical appliances. As the circuit gets more complex (more devices connect to it), it becomes more challenging for the current to flow through the circuit and faults may occur. When any of the faults take place in the system, it is most likely to fail the system and even damage the devices permanently. Thus, measures need to be taken to protect the system as well as the units that run on it.


The circumstance that can potentially pose a risk to the circuit and the appliance includes overcurrent, overheat, short circuit, overload, high/low voltage, and so forth. To prevent the system from damage, the most common circuit protection approach is to open (break) the circuit to stop the current flow. The device that is responsible for this job is called the circuit breaker. Depending on the actual application of the circuit, there are several types of circuit breakers. There are thermostats, motor protection circuit breakers, miniature circuit breakers, thermal fuses, bimetal control switches, and more. Scroll down to see Sang Mao’s circuit breaker selections. If you are looking for the best circuit protection solution for your system, feel free to leave us a message and we will get back to you shortly.

Thermal Circuit Breakers | Overload Protectors

Thermostats | Overheat Protector

Motor Protectors