Close differential relay
Reto Steiner · OSTI OAI (U.S. Department of Energy Office of Scientific and Technical Information) · 1966
Information is presented on: performance of close-differential relays compared with conventional relays; electromagnetic circuit combination of relays that complies with Ohm's law of magnetic circuits; application for monitoring of operating voltage in dc systems, including overvoltage, under-voltage and differential-voltage conditions; in combination with thermistor and four-resistor bridge, relay acts as temperature monitor, or indicator; and use for protecting any device, susceptible to malfunction because of inadequate, or excessive operating voltage, or current, or for arc-light and welding equipment requiring specific system-voltage range for best performance as well as shut-off at given minimum voltage.