Patent ID: 11930563
Assignee: ROSEMOUNT AEROSPACE INC.
Field: Measurement (Instruments)
Classification: CPC G  H | IPC G  H

Claim 8:
9. A heating arrangement monitoring system comprising:
a leakage current measurement circuit configured to measure a heating leakage current, wherein the heating leakage current is either:
a first polarity heating leakage current as a result of applying a first polarity DC voltage to the heating arrangement; or
a second polarity heating leakage current as a result of applying a second polarity DC voltage to the heating arrangement;

a processor, configured to determine a health of the heating arrangement based on one or more measured values of the first polarity heating leakage current and the second polarity heating leakage current;
a polarity selection circuit configured to apply a heater voltage to the heating arrangement using either a first polarity or a second polarity until a system shutdown; and
a polarity control circuit configured to receive a polarity command signal and to direct the polarity selection circuit to apply a selected heater voltage polarity that is either the first polarity or the second polarity;
wherein the processor is configured to:
calculate the first polarity heating leakage current;
calculate the second polarity heating leakage current; and
generate the polarity command signal indicative of a smaller one of the calculated values of the first polarity heating leakage current and the second polarity heating leakage current.