摘要 |
A novel toroidal core current sensor for an AFCI/GFCI Circuit Breaker and a test circuit configuration based thereon is disclosed. The current sensor has a plurality of load current conductors extending therethrough. One of the conductors carrying a load current has a portion of the load current shunted outside the core through a shunt conductor which is connected in parallel with one of the load current conductors. The secondary of the transformer outputs a current value proportional to and substantially less than the load current which may be, for example, detected by a control circuit which compares the current value against predetermined stored criteria and operates a circuit breaker accordingly. In the test circuit a power source and a waveform generator are provided for operating an AFCI\GFCI circuit breaker having the shunted current sensor and injecting test signals into a terminal of the circuit breaker. The unique properties of the shunted current sensor permit a wide range of fault conditions to be applied at low signal power because of the relatively high sensitivity the shunted current sensor provides to the AFCI\GFCI circuit breaker.
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