A smart accessory device is designed to be used with a circuit breaker so as to be able to actuate an operating mechanism of the circuit breaker in order to either open or close the separable contacts of the circuit breaker. The accessory device can be one of a shunt trip, spring release, or under voltage release device. The accessory device continually executes diagnostics to determine whether the power being supplied by an external power source is sufficient to enable the accessory device to actuate the operating mechanism of the associated circuit breaker. If the accessory device determines that the power being supplied by the external source is insufficient, the device triggers an alarm in order to notify a user that the power source is not meeting the power requirements of the device.

A smart accessory device is designed to be used with a circuit breaker so as to be able to actuate an operating mechanism of the circuit breaker in order to either open or close the separable contacts of the circuit breaker. The accessory device can be one of a shunt trip, spring release, or under voltage release device. The accessory device continually executes diagnostics to determine whether the power being supplied by an external power source is sufficient to enable the accessory device to actuate the operating mechanism of the associated circuit breaker. If the accessory device determines that the power being supplied by the external source is insufficient, the device triggers an alarm in order to notify a user that the power source is not meeting the power requirements of the device.

Method for start-up of a field device, wherein for start-up of the field device an energy storage unit (R) for storing electrical energy is charged by means of a power supply (PS), preferably a power-limited power supply (PS), and wherein the electrical energy stored in the energy storage unit (R) is used to supply the field device at least at times with electrical energy, at least during start-up of the field device.