GB907414A - Electric protective circuits - Google Patents

Electric protective circuits

Info

Publication number
GB907414A
GB907414A GB1472759A GB1472759A GB907414A GB 907414 A GB907414 A GB 907414A GB 1472759 A GB1472759 A GB 1472759A GB 1472759 A GB1472759 A GB 1472759A GB 907414 A GB907414 A GB 907414A
Authority
GB
United Kingdom
Prior art keywords
relay
contacts
shunted
transistor
arrangement
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.)
Expired
Application number
GB1472759A
Inventor
Russell Cormack Mccormick
Kenneth Mcrobert
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.)
Ultra Electronics Ltd
Original Assignee
Ultra Electronics 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 Ultra Electronics Ltd filed Critical Ultra Electronics Ltd
Priority to GB1472759A priority Critical patent/GB907414A/en
Publication of GB907414A publication Critical patent/GB907414A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
    • H02H3/02—Details
    • H02H3/025—Disconnection after limiting, e.g. when limiting is not sufficient or for facilitating disconnection

Landscapes

  • Emergency Protection Circuit Devices (AREA)

Abstract

907,414. Protective arrangements. ULTRA ELECTRONICS Ltd. March 24, 1960 [April 30, 1959; Oct. 27, 1959], Nos. 14727/59 and 36414/59. Class 38 (4). A load LD on a D.C. supply is protected from overvoltage transients, first by a delay circuit DL and DC and then by an arrangement which opens contacts r in the line. As shown, the arrangement comprises a Zener diode ZR which, when the overvoltage is sufficient, passes current through an amplifier A to operate a relay R whose contacts r open, so inserting a voltage dropping resistance RR in the line. In an alternative arrangement (Fig. 2, not shown), the Zener diode is connected between a potential divider and the base of a transistor in the collector circuit of which is the relay coil. This coil is shunted by a second diode to protect the transistor, and the relay contacts are not shunted so that the load is disconnected.
GB1472759A 1959-04-30 1959-04-30 Electric protective circuits Expired GB907414A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB1472759A GB907414A (en) 1959-04-30 1959-04-30 Electric protective circuits

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB1472759A GB907414A (en) 1959-04-30 1959-04-30 Electric protective circuits

Publications (1)

Publication Number Publication Date
GB907414A true GB907414A (en) 1962-10-03

Family

ID=10046412

Family Applications (1)

Application Number Title Priority Date Filing Date
GB1472759A Expired GB907414A (en) 1959-04-30 1959-04-30 Electric protective circuits

Country Status (1)

Country Link
GB (1) GB907414A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1285608B (en) * 1964-08-17 1968-12-19 Licentia Gmbh Arrangement to limit overcurrents

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1285608B (en) * 1964-08-17 1968-12-19 Licentia Gmbh Arrangement to limit overcurrents

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