US 12,463,415 B2
Power cutoff device, power cutoff system equipped with same, method for protecting power cutoff device, and protection program
Kenichi Tabata, Kyoto (JP); Daiki Ando, Kyoto (JP); and Hidetoshi Yugen, Kyoto (JP)
Assigned to OMRON CORPORATION, Kyoto (JP)
Filed by OMRON CORPORATION, Kyoto (JP)
Filed on Oct. 20, 2023, as Appl. No. 18/491,058.
Claims priority of application No. 2022-189855 (JP), filed on Nov. 29, 2022.
Prior Publication US 2024/0178654 A1, May 30, 2024
Int. Cl. H02H 5/04 (2006.01); G01R 31/327 (2006.01); H02J 3/14 (2006.01)
CPC H02H 5/04 (2013.01) [G01R 31/3278 (2013.01); H02J 3/14 (2013.01)] 13 Claims
OG exemplary drawing
 
1. A power cutoff device that monitors a temperature of a relay for cutting off a power supply to an electrical device, and determines whether to cut off the power supply, the power cutoff device comprising:
a relay including a drive coil;
a temperature calculation unit configured to calculate a temperature of the drive coil by calculating a resistance value of a resistor that changes with temperature, when the drive coil included in the relay is regarded as the resistor; and
a determination unit configured to determine whether or not to cut off the power supply on the basis of the temperature of the drive coil calculated by the temperature calculation unit, and
wherein the temperature calculation unit calculates the temperature of the drive coil using a first resistor when the relay is in operation and using a second resistor when the relay is not in operation.