Abstract: A switching arrangement is disclosed comprising: a control circuit; a latching relay controlled by the control circuit for connecting an AC source to an AC load; and a relief circuit in parallel with the relay and controlled by the control circuit. The relief circuit has two modes of operation: an inactive mode in which the relief circuit is non-conductive and an active mode in which the relief circuit is at least partially conductive. The relief circuit is partially conductive when spending both a time period in a conductive state and a time period in a non-conductive state during a half-cycle of the AC. The control circuit is configured to switch the relief circuit from inactive mode to active mode, and upon switching to active mode, to set the relief circuit as partially conductive for at least two half-cycles, wherein the proportion of time the relief circuit is conductive compared to non-conductive is increased for successive ones of the at least two half-cycles.
Type:
Grant
Filed:
December 20, 2010
Date of Patent:
May 26, 2015
Assignees:
Tyco Electronics UK Ltd., Raychem International (Irish Branch)
Inventors:
Brendan Normoyle, Philip Foxley, Melvyn McGann, Leslie Allen
Abstract: A switching arrangement is disclosed comprising: a control circuit; a latching relay controlled by the control circuit for connecting an AC source to an AC load; and a relief circuit in parallel with the relay and controlled by the control circuit. The relief circuit has two modes of operation: an inactive mode in which the relief circuit is non-conductive and an active mode in which the relief circuit is at least partially conductive. The relief circuit is partially conductive when spending both a time period in a conductive state and a time period in a non-conductive state during a half-cycle of the AC. The control circuit is configured to switch the relief circuit from inactive mode to active mode, and upon switching to active mode, to set the relief circuit as partially conductive for at least two half-cycles, wherein the proportion of time the relief circuit is conductive compared to non-conductive is increased for successive ones of the at least two half-cycles.
Type:
Application
Filed:
December 20, 2010
Publication date:
February 27, 2014
Applicants:
RAYCHEM INTERNATIONAL (IRISH BRANCH), TYCO ELECTRONICS UK LTD.
Inventors:
Brendan Normoyle, Philip Foxley, Melvyn McGann, Leslie Allen
Abstract: A monitoring device (1) for monitoring a condition of a surge arrester comprises monitoring means (210) adapted to monitor a leakage current recovery of the surge arrester after an occurrence of a surge over a recovery monitoring period following the surge event. The monitoring of recovery of surge arrester leakage current following the surge event in the arrester is used to estimate the time to recovery of the leakage currents and to identify a deterioration in the condition of the arrester by comparing the evolution of the time to recovery over time.
Type:
Application
Filed:
November 30, 2010
Publication date:
September 20, 2012
Applicant:
Raychem International (Irish Branch)
Inventors:
Brendan Normoyle, Padraig Fitzgerald, Mark Leyden, Jean-Christophe Bouche