Patent ID: 8699201
Filing Date: 2014-04-15
Classification: H01H

Abstract:
1. A relay failure detecting device comprising: an opening-closing unit that is driven by a coil for opening and closing a current pathway; a detecting unit that detects a current value of a current flowing in the coil; an opening-closing instructing unit that outputs an instruction signal to instruct opening and closing of the opening-closing unit; a failure detecting unit that detects a failure in the opening-closing unit by using the current value output by the detecting unit within a predetermined period of time starting from when the instruction signal is output; and a differentiating unit that receives input of the current values, which have been detected by the detecting unit, for the predetermined period of time and outputs a differentiated waveform obtained by differentiating the current values received in the predetermined period of time, the differentiating unit including a high-pass filter and a low-pass filter, wherein when a pulse based on the differentiated waveform is detected, the failure detecting unit detects a failure in the opening-closing unit, and the failure detecting unit detects a failure in the opening-closing unit by comparing a differential value, calculated by differentiating each obtained current value, with a corresponding differential value calculated in the past.