摘要 |
An electronic trip unit for a motor circuit breaker of an electric motor includes at least one detection unit configured to sense at least one current that is delivered to the electric motor. The unit further including a discriminator circuit, the discriminator circuit being in a first state when no measured current value exceeds a predefined trip threshold, and being in a second state when at least one measured current value exceeds the predefined trip threshold. The discriminator circuit includes an output for controlling the motor; a voltage-limiting component having a breakdown voltage; a resistor; and a switching unit configured to, in the first state, switch the control signal to the first level, and, in the second state, switch the control signal to the second level, the switching unit being configured to be switched by a voltage drop across the resistor.
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