Vacuum breakers

VR-Series medium-voltage vacuum replacement (MVVR) breakers are designed to replace air magnetic circuit breakers. They are reversible if cell structure modifications are necessary, and they only require one outage for removal and installation.
Circle 301

Vacuum contactors

The Sirius 3R line of vacuum contactors is designed for current applications greater than 225A, including 225A, 265A, 300A, 400A, and 500A models. Contacts are also enclosed in a vacuum bottle, so there are no opening arcs or arcing gases. The contactors are available with universal current conventional coils (24V AC/DC to 600V AC/DC) and electronic coil.
Siemens Energy & Automation
Circle 302

Protection relay

The SEL 387A is a current differential and overcurrent protection relay for two-winding transformers and other two-port electrical apparatus. It provides the advanced features and options previously available only to three-winding or larger customers. Temperature meters provide operating data, while an intelligent breaker monitor keeps track of the breaker operations for timely scheduling of maintenance.
Schweitzer Engineering Laboratories
Circle 306

Current-limiting fuses

Amp-Trap 2000 fuses minimize let-through current by opening in less than one-quarter cycle at fault currents as high as 300kA. These are available in Class L, Class J, Class RK-1, and Class CC fuses and in a range of amperages, with time delay and 2:1 selectivity.
Ferraz Shawmut
Circle 307


The SmartLock GFCI meets the new UL requirements for GFCIs that go into effect in January 2003. In addition to increased corrosion resistance and a diagnostic indication of line/load miswiring, the device will prevent the reset button from re-engaging if ground fault protection is compromised as a result of transient voltage surges or lightning strikes.
Circle 304

Compact power circuit breaker

Masterpact NT circuit breakers offer multiple cradle termination configurations, draw-out capability, and field-installable accessories, terminations, and control options. The unit is 70% smaller than its predecessor, allowing for higher density in switchgear and switchboards.
Square D/Schneider Electric
Circle 300

Modular fuseholder

The Optima OPM-NG fuseholder incorporates IP-20 finger-safe fusible features that meet global standards for minimizing contact with current-carrying parts. The DIN rail spring eliminates the need for tools for installation. The fuseholder's 45-mm design matches it with 32A IEC motor circuits. An auxiliary contact block provides status indication of the fuse carriage position and can be used to open the control circuit when a fuse is removed from the device.
Cooper Bussmann
Circle 305