State-of-the-art Technology Applied to Siemens IEC Sentron Series

Flexibility of Application

Siemens IEC Sentron Series molded case circuit breakers may be used for circuit protection in individual enclosures, switchboards, lighting and power panel boards as well as in motor control centers.

The IEC Sentron Series circuit breakers protect cables, wiring, busbars, motors, transformers as well as plant components and consumers from thermal-overload and short-circuits.

Trip Free Mechanism

By design the Siemens Sentron series circuit breakers use a trip-free mechanism which open the circuit breaker contacts under overload and short circuit conditions, even if the breaker handle is held in the ON position.

IEC Rated

Siemens Sentron Series circuit breakers have been tested and qualified to the rugged requirements set out in IEC 947-2 requirements.

Quick-make, Quick-break Mechanism

This type of mechanism minimizes arcing during operation as well as preventing the contacts from being “teased” into the “ON” position.

Front-Adjustable Magnetic Trip

On the 250A frame and above, adjustment buttons are provided to set the instantaneous trip setting in event of a short circuit. Any current surge above the trip setting produces a magnetic field which instantly actuates the trip mechanism and opens the breaker.

Thermal-trip

This provides protection against sustained overloads. A bi-metallic element in each conductor path reacts time-wise in inverse proportion to the current. If a circuit is overloaded, heat resulting from excessive current flow cause the bi-metal to bend, actuating the trip mechanism to open the breaker.

Push-to-Trip

Periodic tripping for maintenance purposes are obtained by using the “Push-to-Trip” button on all Sentron Series circuit breakers.

Contacts

All contacts are alloy materials designed to give above normal life expectancy during in service use.

ARC-Chutes

Arc chutes are designed to confine, divide and extinguish an arc each time that the breaker contacts interrupt a short circuit. The arc chute therefore must dissipate the arcs that are caused when the circuit breaker interrupts current flow. It contains a stack of U-shaped steel plates held together by insulating material. The steel plates divide the arc and cools the gases generated by the arc.