Method And Device For Switching A Contactor

摘要

A low voltage contactor for connecting and disconnecting a three-phase load to an electric power including a coil, main contacts operated by the coil and an electronic control circuit for controlling voltage supplied to the coil. The electronic control circuit includes a pre-arranged time point selection scheme and is further adapted to select a time point from the pre-arranged time point selection scheme as a time delay, and initiate an instant opening command based on the selected time point.

主权项

1. A method for switching a low voltage contactor connecting a three-phase load and including a coil and three contacts operated by the coil, wherein each of contacts is connected to each of the phases, the method comprising,
providing an electronic control circuit for controlling voltages supplied to the coil,characterized in that the method further comprises steps of
constructing a pre-arranged time point selection scheme including a plurality of time points distributed in a period of the control voltage of the electronic control circuit, selecting a time point from the pre-arranged time point selection scheme, supplying the selected time point as a time delay, and initiating an instant opening command based on the selected time point, wherein the time points are constructed in the pre-arranged time point selection scheme in a way such that the initiated opening commands based thereon are evenly distributed on each of the contacts.