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JPS54149849A - Open-phase protective relay - Google Patents

Open-phase protective relay

Info

Publication number
JPS54149849A
JPS54149849A JP5717478A JP5717478A JPS54149849A JP S54149849 A JPS54149849 A JP S54149849A JP 5717478 A JP5717478 A JP 5717478A JP 5717478 A JP5717478 A JP 5717478A JP S54149849 A JPS54149849 A JP S54149849A
Authority
JP
Japan
Prior art keywords
open
circuit
phase
pulses
output
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP5717478A
Other languages
Japanese (ja)
Other versions
JPS6047816B2 (en
Inventor
Yasuo Takasaki
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Fuji Electric Co Ltd
Original Assignee
Fuji Electric Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Fuji Electric Co Ltd filed Critical Fuji Electric Co Ltd
Priority to JP5717478A priority Critical patent/JPS6047816B2/en
Publication of JPS54149849A publication Critical patent/JPS54149849A/en
Publication of JPS6047816B2 publication Critical patent/JPS6047816B2/en
Expired legal-status Critical Current

Links

Landscapes

  • Emergency Protection Circuit Devices (AREA)

Abstract

PURPOSE: To accurately detect an open-phase condition by simple constitution, by converting a pulsating portion of three-phase full-wave rectifying output into pulses with fixed pulse width and amplitude, and by obtaining open phase discriminating output by leveling the pulses.
CONSTITUTION: The output of a current transformer 10 for detecting three-phase currents is rectified by means of a full-wave rectifying circuit 12, and only the pulsating portion is fed to a Schmidt circuit 16 for converting wave-forms by means of a low-pass filter 14. The pulsating portion is converted into square wave pulses by means of the Schmidt circuit 16 and supplied to a single-stabilizing multi- circuit 18 as trigger input, and pulse voltage is leveled by means of an integration circuit 20. The pulse voltage is compared with reference voltage by means of a Schmidt circuit 22 for discrimination, and detecting signals are gained. Thus, an open-phase condition can be detected easily and accurately because voltage leveled and converted into effective value remarkably reduces under the open-phase condition.
COPYRIGHT: (C)1979,JPO&Japio
JP5717478A 1978-05-16 1978-05-16 Phase loss protection relay Expired JPS6047816B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP5717478A JPS6047816B2 (en) 1978-05-16 1978-05-16 Phase loss protection relay

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP5717478A JPS6047816B2 (en) 1978-05-16 1978-05-16 Phase loss protection relay

Publications (2)

Publication Number Publication Date
JPS54149849A true JPS54149849A (en) 1979-11-24
JPS6047816B2 JPS6047816B2 (en) 1985-10-23

Family

ID=13048170

Family Applications (1)

Application Number Title Priority Date Filing Date
JP5717478A Expired JPS6047816B2 (en) 1978-05-16 1978-05-16 Phase loss protection relay

Country Status (1)

Country Link
JP (1) JPS6047816B2 (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11206003A (en) * 1998-01-13 1999-07-30 Fuji Electric Co Ltd Inverter device

Also Published As

Publication number Publication date
JPS6047816B2 (en) 1985-10-23

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