FISRE special report

Insulation resistance of electronic circuits in smoke - quantification of the problem and needed countermeasures

Johan Mangs, Olavi Keski-Rahkonen, Mika Letonsaari

Research output: Chapter in Book/Report/Conference proceedingChapter or book articleProfessional

Abstract

Acute effects of smoke on insulation resistance of electronics used in programmable automation circuitry in nuclear power plants were studied experimentally. Real and mock-up circuitry was exposed to smoke in four tests. Relevant physical parameters of smoke and electrical performance of circuitry was measured online for a period of an hour. It was noticed that insulation resistance decreased by three orders of magnitude due to soot deposits on surfaces on uncoated circuitry. For real commercial circuits, coated by a protective lacquer layer, no electrical changes were observed. A quantitative model for smoke exposure and deposition on surfaces is proposed based on existing physical models of aerosols. A consistent picture of the relevant processes was found, and an easy calculation method for smoke hazard estimation for PSA-work is proposed for insulation resistance deterioration. This model allows also estimation of the required performance of protective coatings to prevent parasitic leakage currents between different parts of circuitry.
Original languageEnglish
Title of host publicationFINNUS: The Finnish Research Programme on Nuclear Power Plant Safety
Subtitle of host publicationInterim Report 1999 - August 2000
Place of PublicationEspoo
PublisherVTT Technical Research Centre of Finland
Pages192-202
ISBN (Electronic)951-38-5751-4
ISBN (Print)951-38-5750-7
Publication statusPublished - 2000
MoE publication typeD2 Article in professional manuals or guides or professional information systems or text book material

Publication series

NameVTT Tiedotteita - Research Notes
PublisherVTT
Number2057
ISSN (Print)1235-0605
ISSN (Electronic)1455-0865

Fingerprint

Smoke
Insulation
Networks (circuits)
Lacquers
Protective coatings
Soot
Leakage currents
Nuclear power plants
Aerosols
Deterioration
Hazards
Electronic equipment
Deposits
Automation

Cite this

Mangs, J., Keski-Rahkonen, O., & Letonsaari, M. (2000). FISRE special report: Insulation resistance of electronic circuits in smoke - quantification of the problem and needed countermeasures. In FINNUS: The Finnish Research Programme on Nuclear Power Plant Safety: Interim Report 1999 - August 2000 (pp. 192-202). Espoo: VTT Technical Research Centre of Finland. VTT Tiedotteita - Research Notes, No. 2057
Mangs, Johan ; Keski-Rahkonen, Olavi ; Letonsaari, Mika. / FISRE special report : Insulation resistance of electronic circuits in smoke - quantification of the problem and needed countermeasures. FINNUS: The Finnish Research Programme on Nuclear Power Plant Safety: Interim Report 1999 - August 2000. Espoo : VTT Technical Research Centre of Finland, 2000. pp. 192-202 (VTT Tiedotteita - Research Notes; No. 2057).
@inbook{ee549ee60a1241ffabe29a3cee20af02,
title = "FISRE special report: Insulation resistance of electronic circuits in smoke - quantification of the problem and needed countermeasures",
abstract = "Acute effects of smoke on insulation resistance of electronics used in programmable automation circuitry in nuclear power plants were studied experimentally. Real and mock-up circuitry was exposed to smoke in four tests. Relevant physical parameters of smoke and electrical performance of circuitry was measured online for a period of an hour. It was noticed that insulation resistance decreased by three orders of magnitude due to soot deposits on surfaces on uncoated circuitry. For real commercial circuits, coated by a protective lacquer layer, no electrical changes were observed. A quantitative model for smoke exposure and deposition on surfaces is proposed based on existing physical models of aerosols. A consistent picture of the relevant processes was found, and an easy calculation method for smoke hazard estimation for PSA-work is proposed for insulation resistance deterioration. This model allows also estimation of the required performance of protective coatings to prevent parasitic leakage currents between different parts of circuitry.",
author = "Johan Mangs and Olavi Keski-Rahkonen and Mika Letonsaari",
year = "2000",
language = "English",
isbn = "951-38-5750-7",
series = "VTT Tiedotteita - Research Notes",
publisher = "VTT Technical Research Centre of Finland",
number = "2057",
pages = "192--202",
booktitle = "FINNUS: The Finnish Research Programme on Nuclear Power Plant Safety",
address = "Finland",

}

Mangs, J, Keski-Rahkonen, O & Letonsaari, M 2000, FISRE special report: Insulation resistance of electronic circuits in smoke - quantification of the problem and needed countermeasures. in FINNUS: The Finnish Research Programme on Nuclear Power Plant Safety: Interim Report 1999 - August 2000. VTT Technical Research Centre of Finland, Espoo, VTT Tiedotteita - Research Notes, no. 2057, pp. 192-202.

FISRE special report : Insulation resistance of electronic circuits in smoke - quantification of the problem and needed countermeasures. / Mangs, Johan; Keski-Rahkonen, Olavi; Letonsaari, Mika.

FINNUS: The Finnish Research Programme on Nuclear Power Plant Safety: Interim Report 1999 - August 2000. Espoo : VTT Technical Research Centre of Finland, 2000. p. 192-202 (VTT Tiedotteita - Research Notes; No. 2057).

Research output: Chapter in Book/Report/Conference proceedingChapter or book articleProfessional

TY - CHAP

T1 - FISRE special report

T2 - Insulation resistance of electronic circuits in smoke - quantification of the problem and needed countermeasures

AU - Mangs, Johan

AU - Keski-Rahkonen, Olavi

AU - Letonsaari, Mika

PY - 2000

Y1 - 2000

N2 - Acute effects of smoke on insulation resistance of electronics used in programmable automation circuitry in nuclear power plants were studied experimentally. Real and mock-up circuitry was exposed to smoke in four tests. Relevant physical parameters of smoke and electrical performance of circuitry was measured online for a period of an hour. It was noticed that insulation resistance decreased by three orders of magnitude due to soot deposits on surfaces on uncoated circuitry. For real commercial circuits, coated by a protective lacquer layer, no electrical changes were observed. A quantitative model for smoke exposure and deposition on surfaces is proposed based on existing physical models of aerosols. A consistent picture of the relevant processes was found, and an easy calculation method for smoke hazard estimation for PSA-work is proposed for insulation resistance deterioration. This model allows also estimation of the required performance of protective coatings to prevent parasitic leakage currents between different parts of circuitry.

AB - Acute effects of smoke on insulation resistance of electronics used in programmable automation circuitry in nuclear power plants were studied experimentally. Real and mock-up circuitry was exposed to smoke in four tests. Relevant physical parameters of smoke and electrical performance of circuitry was measured online for a period of an hour. It was noticed that insulation resistance decreased by three orders of magnitude due to soot deposits on surfaces on uncoated circuitry. For real commercial circuits, coated by a protective lacquer layer, no electrical changes were observed. A quantitative model for smoke exposure and deposition on surfaces is proposed based on existing physical models of aerosols. A consistent picture of the relevant processes was found, and an easy calculation method for smoke hazard estimation for PSA-work is proposed for insulation resistance deterioration. This model allows also estimation of the required performance of protective coatings to prevent parasitic leakage currents between different parts of circuitry.

M3 - Chapter or book article

SN - 951-38-5750-7

T3 - VTT Tiedotteita - Research Notes

SP - 192

EP - 202

BT - FINNUS: The Finnish Research Programme on Nuclear Power Plant Safety

PB - VTT Technical Research Centre of Finland

CY - Espoo

ER -

Mangs J, Keski-Rahkonen O, Letonsaari M. FISRE special report: Insulation resistance of electronic circuits in smoke - quantification of the problem and needed countermeasures. In FINNUS: The Finnish Research Programme on Nuclear Power Plant Safety: Interim Report 1999 - August 2000. Espoo: VTT Technical Research Centre of Finland. 2000. p. 192-202. (VTT Tiedotteita - Research Notes; No. 2057).