Thermal Circuit Breakers for High Nominal Current

Phoenix Contact offers a TCP with 16 A and 20 A plugs to protect devices with higher nominal currents. As an extension of the TCP family, these plugs offer the same reliable overload protection in a slim package. While the original TCP plugs use a 6-mm-wide base, these plugs require a 10-mm-wide base to accommodate the higher ampere ratings. The plugs fit into the PT 10-FSI/C standard terminal block bases with or without LED status indication. In combination with the terminal block bases, applications up to 250 V_AC and 65 V_DC can be equipped with basic protection. TCP products are suitable for replacing existing fuses with re-closable variants, thereby minimizing maintenance effort. The two-piece construction offers the convenience of a simple change-out. Potential distribution can easily be achieved by the terminal block bridge shaft which considerably reduces installation effort. This series offers two distinct operational characteristics: on/off and trip reset or only trip reset.

Thermal circuit breakers provide optimum protection against overload for inductive and resistive loads in power distribution systems, control cabinets, and other equipment. Thermal breakers are ideal for applications in which a large start-up current is involved. For example, they are great for protecting actuators, sensors, motors, heating elements and fans, lighting, solenoid valves, transformers, and onboard networks. They are resistant to high starting currents such as those that occur when starting a motor or switching a transformer on. However, thermal circuit breakers do not offer rapid protection from short-circuits compared to other protection technologies.

Thermal circuit breakers are normally tripped via a bimetal strip. In the event of a fault, the bimetal heats up and disconnects the circuit. As a rule, the higher the overload the faster the thermal circuit breaker trips. The devices can be switched on again at any time.