New PKE motor-protective circuit-breaker with SmartWire-DT

The overriding advantage of the PKE motor-protective circuit-breaker compared with conventional alternatives lies in the expanded drive monitoring. The diagnostic, status or overload messages show the actual flow of current and the status of the overload trip device. Moreover, the actual motor current can be continuously displayed and analysed via Eaton's SmartWire-DT communication system for switchgear without the need for any additional components.

Depending on the drive application, the following operating states can be differentiated: motor switched off, motor under load, motor no-load, motor operation, motor overload and motor fault. The separate load limits and the time response behavior can be individually programmed and adapted to all drive tasks. Emerging faults can be identified in good time thanks to the transmission of motor current and overload status. This enables the system operator to intervene in the production process before an undesirable interruption occurs. Of particular interest in this case is the option to operate the PKE as a motor protection relay. The motor-protective circuit-breaker is then not triggered in the event of overload; only the associated contactor is disconnected. Once the overload situation is rectified, the motor can be switched on again via the control unit without the maintenance personnel having to first reset the protection switch. This means that the PKE can be installed in locations that are not readily accessible.

Predicting trips and preventing downtime

Frozen elevating conveyors and typical belt conveyor scenarios when transporting coarse bulk material can only be insufficiently tracked in conventional drive control systems, as individual motors or belts at standstill are only indirectly interpreted via the switching states of the motor-protective circuit-breaker and power contactor. A hardware solution such as a speed sensor, load-shedding relay etc. is additionally required for a specific, reliable response. In the event of overload, the drive is immediately disconnected when the set current value is exceeded and a fault is signaled, thereby protecting the motor from being damaged. This results in unscheduled, time-consuming and costly downtime because conventional analogue I/O technology cannot image the current motor current as continuously and in such detail as the PKE, so the motor has to be shut down more often than necessary.

Follow the link for more information about the PKE motor-protective circuit-breaker with SmartWire-DT communication.