Murr.  Along with the detection and reporting of overloads, the newly developed DC-Powerswitch device also ensures effective protection of the connected resistors by switching off like a fuse.
The DC Powerswitch can be used in DC current applications up to 850 V DC.
The UL certification 1077 under E357442 also allows the product to be offered on the American and Canadian markets.

The great advantage of the DC-Powerswitch lies in its precise adaptability to the particular application. A DC-Powerswitch can be selected in the appropriate interval for rated currents between 1 and 40 amps and calibrated to that particular rated current. The DC-Powerswitch detects both continuous overloads and short-term overload peaks, comparable to the mode of action of a DC-based motor protection switch. Occurring faults are reported by a potential-free NC and NO contact. After fault clearance, the device can be switched on again like a normal automatic circuit breaker.

This allows damages due to operational disturbances (such as by a broken-down chopper transistor) with possible fires and harm to the environment to be effectively prevented by the usage of DC-Powerswitch resistors as braking resistors in the DC link of frequency converters. The "intrinsically safe resistors" often required for automotive or elevator applications is achieved in this way.

The usage of the DC-Powerswitch in the cycled power outflow for braking resistors offers several advantages to the customer:

• The DC-Powerswitch can be freely scaled – this ensures the best possible protection at all times.
• Development of intrinsically safe resistors up to a continuous power of approx. 22 kW (depending on the Ohm value) and up to 100 times the peak power (can also be cascaded in a special design for ever higher power dissipations).
• Thanks to the self-protecting braking resistors, the main contactor as a "Safety-Stop" switching element can be eliminated for applications in the drive area.
• Elimination of a semi-conductor fuse for securing the braking resistors and the connecting cable against short circuits.
• Cross-section reduction of the supply line of the braking resistors.
• Along with the pre-fuse in front of the frequency converter prescribed by VDE and UL/NEC, additional fuse elements with regard to brake resistors can be eliminated in networks secured up to 5kA.

The device for top-hat rail mounting with a construction width of 62.5 mm can be installed in properly prepared control cabinets or device terminal boxes.  The DC-Powerswitch is now available in 10 different current intervals between 1 and 40 amps.