Isolation monitor

US9046559B2 · kind B2 · utility

Assignee

• Curtis Instruments, Inc. · US

Inventors

• Ryan Lindsay · Waterloo, US
• Roger White · Livermore, US
• Scott Bowman · Fairfax, US
• John Cochoy · Statesboro, US

Key dates

• Filing date: May 9, 2012
• Grant date: Jun 2, 2015
• Expiry date: Mar 15, 2033

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02T10/70
• WIPO field: Transport
• WIPO sector: Mechanical engineering

Abstract

An isolation monitor is disclosed in which a switchable bias voltage is imposed on a chassis ground. An isolation voltage is measured when a bias voltage is applied. When there are no electrical faults, the isolation voltage swings up and down to known values. When a fault occurs, the isolation voltage will not to swing to the known values, and thus the isolation resistance can be measured and alarm generated if the isolation resistance falls below a threshold value.