ABB presents a new generation of miniature circuit breakers (MCBs) for electrical equipment that provides higher levels of strength, performance and savings, while remaining compliant with the UL 1077 standard. The new ST 200 M supplementary protectors are intended for use within industrial control panels, appliances and other equipment to protect against overcurrent where branch-circuit protection already has been provided or is not required.

The ST 200 M series advances the capabilities of the previous S200 and S200P supplementary protectors from ABB, reducing the number of parts that users need to order and making it easier for distributors, OEMs and consumers to do business with ABB.

The new supplementary protectors are built with a thermoplastic housing, replacing the often brittle thermoset plastic used in the S200 and S200P. Thermoplastic material significantly reduces the potential for transportation damages. Additionally, the ST 200 M offers a higher interrupt rating — up to 10 kA — than earlier versions. The voltage ratings of the ST 200 M are 480Y/277 VAC and 60/125 VDC, which eliminate the necessity of using two different product lines for AC and DC applications. The ST 200 M carries a short-circuit current classification of U2, which expands its range of applications.

The ST 200 M features a red/green contact position indicator for increased safety by indicating the actual position of the contacts. Its calibration temperature of 104 degrees Fahrenheit (40 degrees Celsius) reduces derating in industrial control panels at higher ambient temperatures.

Installation of the ST 200 M is easier than competing supplementary protectors, in part because it features ABB’s patented twin terminals with captive screws for field wiring up to AWG 4. The new labeling of the ST 200 M is done with lasers, providing higher resistance to fading than conventional ink-pad printing to enable easy identification of product type, rating and approvals, even when it is installed on the panel.

As the newest member of ABB’s large family of protection devices, ST 200 M is part of a complete  solution for all control panel and power distribution applications, incorporating a comprehensive range of UL 1077 and UL 489 (circuit breaker) products. Complying with UL, CSA and IEC standards, ST 200 M is ideal for wide-ranging applications in global markets.

The product will be commercially available as of January 1, 2019.