Absence of voltage detector

Patent metadata

Field	Value
Publication number	US-11988693-B2
Application number	US-202117517041-A
Country	US
Kind code	B2
Filing date	Nov 2, 2021
Priority date	Feb 10, 2017
Publication date	May 21, 2024
Grant date	May 21, 2024

Abstract

An absence of voltage indicator has an isolation circuit, an FM modulator attached to the isolation circuit, a reference oscillator, and a mixer attached to the reference oscillator and the FM modulator, wherein the output of the mixer is the difference of the two signals. In one embodiment, the FM modulator includes a variable capacitor which varies in response to a voltage in parallel to a fixed capacitor and an inductor in parallel to the capacitors.

First claim

The invention claimed is:

1. A method for testing the conductive continuity of a lead line of a device to a power line comprising:
providing a capacitor charged to a known voltage;
providing a high value resistor connecting the powerline to ground;
discharging the capacitor via the powerline;
measuring a decay time of the capacitor; and
determining whether the lead line of the device is conductively connected to the power line based upon the decay time.

Assignees

• Panduit Corp

Inventors

• Bolouri-Saransar Masud

Classifications

• G01R19/155 Primary

  Indicating the presence of voltage · CPC title

• G01R15/16

  using capacitive devices · CPC title

• G01R19/0084

  Measuring voltage only · CPC title

• G01R19/18

  using conversion of DC into AC, e.g. with choppers · CPC title

• G01R31/2829

  Testing of circuits in sensor or actuator systems (testing of apparatus for measuring electric or magnetic variables G01R35/00; testing of indicating or recording apparatus G01D; in airbag systems B60R21/0173; checking gas analysers G01N33/007; monitoring or fail-safe circuits for electromagnets H01F7/1844) · CPC title