# US 4,396,719 A · Method of estimating the insulation life of a resin insulator

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 4,396,719 A
- Document ID: US4396719A
- Status: Granted
- Kind: A
- Application number: 06/253,765
- Filed: 1981-03-25
- Granted: 1983-08-02
- Earliest claimed: 1979-07-25
- Assignees: Mitsubishi Denki Kabushiki Kaisha
- Inventors: Mitsuyo Asahi; Junzou Enomoto; Takao Tanaka; Aiichiro Hashizume
- Web page: https://patentgrep.com/patent/US4396719A

## CPC

- G01N 33/442: {Resins; Plastics}
- G01R 31/1263: {of solid or fluid materials, e.g. insulation films, bulk material; of semiconductors or LV electronic components or parts; of cable, line or wire insulation}
- Y10T 436/20: Oxygen containing
- Y10T 436/22: Hydrogen, per se
- Y10T 436/23: Carbon containing
- G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q)
- G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12)
- Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION

## Abstract

Either a monitoring resin piece associated with an electrical appliance or a resin piece forming a part of the insulating components of the electrical appliance is taken out after the electrical appliance has been operated for a suitable period of time, and either the ratio of the number of hydrogen atoms to the number of carbon atoms or the ratio of the number of oxygen atoms to the number of carbon atoms is measured to estimate the insulation life of the resin insulator of the electrical appliance.

## Claims

### Claim 1

A method of estimating the insulation life of a resin insulator in an electrical appliance, comprising the steps of:
providing at least one monitoring resin insulator sample in association with said appliance, said sample having the same insulating characteristics as said insulator in said appliance and said sample being made of a resin insulator material having a hydrogen to carbon atom ratio which varies with lifetime to a greater extent than the hydrogen to carbon atom ratio of said resin insulator in said appliance, and
measuring the ratio of the hydrogen atoms to the carbon atoms in said sample, whereby said measured ratio provides an indication of the deterioration of the insulation breakdown voltage of said resin insulator.

### Claim 2 (depends on 1)

The method of claim 1 wherein the step of providing at least one monitoring resin insulator sample comprises providing a multiplicity of said resin insulator samples in association with said appliance, and wherein the step of measuring comprises periodically measuring the hydrogen-carbon atom ratios of different ones of said samples to provide periodic estimates of the insulation life of said resin insulator.

### Claim 3

A method of estimating the insulation life of a resin insulator in an electrical appliance, comprising the steps of:
providing at least one monitoring resin insulator sample in association with said appliance, said sample having the same insulating characteristics as said insulator in said appliance and said sample being made of a resin insulator material having a oxygen to carbon atom ratio which varies with lifetime to a greater extent than the oxygen to carbon atom ratio of said resin insulator in said appliance, and
measuring the ratio of the oxygen atoms to the carbon atoms in said sample, whereby said measured ratio provides an indication of the deterioration of the insulation breakdown voltage of said resin insulator.

### Claim 4 (depends on 3)

Themethod of claim 3 wherein the step of providing at least one monitoring resin insulator sample comprises providing a multiplicity of said resin insulator samples in association with said appliance, and wherein the step of measuring comprises periodically measuring the oxygen-carbon atom ratios of different ones of said samples to provide periodic estimates of the insulation life of said resin insulator.