Becker Mining America designed the Hot Circuit Detector to protect the miner, prevent motor dam- age and maximize production. Malfunctions such as a stuck contactor bottle or stuck mechanical contact can leave the motor circuit energized, undetected by the mine electrician. Another anomaly is when a bottle or contact fails to close, resulting in single phasing and eventually damaging the motor. Also, if a circuit to a hydraulic motor or fan operates in reverse sequence this may result in dangerous or damaging consequences.
The device benefits the mine by providing indication and contactor/circuit breaker control when the voltage and/or phase rotation are not correct.
The Hot Circuit Detector indicates that all phases are present, or if one or more phases are lost, it indicates which of the phases are missing and can trip out the circuit. It also allows quick and easy determination of phase sequence (either ABC or CBA), and if reverse sequence can trip the circuit
The unit is available in 120vac or 480vac and can be configured with intermediate devices to monitor voltages up to 38KV. The unit is also available with a 240vac, 10amp normally open con- tact or fail safe contact. Note that fusing should be incorporated as required by MSHA.
SMC’s low voltage connectors are rugged, trouble free devices providing quick, confident connect/disconnect advantages to AC or DC line or switchgear from portable mining equipment to self-propelled machinery. They are available from 225 Amperes to 800 Amperes up to 1000 VAC and 600 VDC. Cable sizes range from #8 to 500 MCM.