US 12,241,935 B2
Redundant contactors with data-based preventive maintenance replacement indicators
Thomas P. Buescher, Webster Groves, MO (US)
Assigned to Copeland Comfort Control LP, St. Louis, MO (US)
Filed by Copeland Comfort Control LP, St. Louis, MO (US)
Filed on Dec. 7, 2022, as Appl. No. 18/077,089.
Claims priority of provisional application 63/296,146, filed on Jan. 3, 2022.
Prior Publication US 2023/0213582 A1, Jul. 6, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. G01R 31/327 (2006.01); G08B 5/36 (2006.01); G08B 21/18 (2006.01)
CPC G01R 31/3278 (2013.01) [G08B 5/36 (2013.01); G08B 21/185 (2013.01)] 32 Claims
OG exemplary drawing
 
1. A contactor comprising:
a processor; and
first, second, and third relays including respective first, second, and third relay contacts and configured to be operable by the processor to electrically connect or disconnect a load to or from a voltage input;
wherein the processor is configured to determine a relay failure condition when:
a voltage drop across at least one of the first, second, and third relays is lower than a voltage drop across at least one other of the first, second, and third relays after the first, second, and third relays are de-energized; or
a voltage drop across at least one of the first, second, and third relays is higher than a voltage drop across at least one other of the first, second, and third relays after the first, second, and third relays are energized.