A 600-volt enclosed limiter for network use

The extension of the conventional network system to industrial plants has established requirements for a higher-voltage limiter. The network system has been adopted as a standard by many utilities for 120–208-volt distribution, whereas industrial-plant distribution is usually at higher voltages up to 600 volts due to the predominance of power load. The requirements of a limiter for this service are more severe, due to the proximity of operating personnel and increased interrupting duty associated with higher voltages and shorter cable runs. A new totally enclosed limiter has been developed for this application. This limiter embodies new principles of operation and will interrupt fault currents in excess of 50,000 amperes at 600 volts without perceptible noise or visible demonstration.