Patent ID: 9551755
Date: 2017-01-24
CPC Classifications: B60L,G01R,H01H,Y02T,Y04S

Claim:
1. A relay welding diagnostic apparatus configured to be operated by switching between a relay diagnosis mode and a leakage detection mode, the relay diagnosis mode being configured to determine whether relays which are respectively provided on a P electrode side and an N electrode side of a voltage line connecting a charging facility and a battery together are welded, the leakage detection mode being configured to detect a leakage in the voltage line, the relay welding diagnostic apparatus comprising: an AC signal output circuit that supplies a predetermined AC voltage to the voltage line, the AC signal output circuit being provided separately from the charging facility; a peak value measurement section that measures a peak value of the voltage supplied to the voltage line from the AC signal output circuit; and a comparison diagnosis section that compares the peak value with a threshold value, wherein in the leakage detection mode, the comparison diagnosis section detects a leakage by comparing the peak value with a threshold value for the leakage detection mode, and in the relay diagnosis mode, the comparison diagnosis section determines a state of the relay by comparing the peak value with a threshold value for the relay diagnosis mode that is different from the threshold value for the leakage detection mode, and determines whether the relay is welded on a basis of the state of the relay thus determined and a state set to the relay.