GB706571A - An improved device for measuring electric currents - Google Patents
An improved device for measuring electric currentsInfo
- Publication number
- GB706571A GB706571A GB1825151A GB1825151A GB706571A GB 706571 A GB706571 A GB 706571A GB 1825151 A GB1825151 A GB 1825151A GB 1825151 A GB1825151 A GB 1825151A GB 706571 A GB706571 A GB 706571A
- Authority
- GB
- United Kingdom
- Prior art keywords
- conductors
- magnetic circuit
- instrument
- plunger
- difference
- 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
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R15/00—Details of measuring arrangements of the types provided for in groups G01R17/00 - G01R29/00, G01R33/00 - G01R33/26 or G01R35/00
- G01R15/14—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks
- G01R15/18—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks using inductive devices, e.g. transformers
- G01R15/186—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks using inductive devices, e.g. transformers using current transformers with a core consisting of two or more parts, e.g. clamp-on type
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Measuring Instrument Details And Bridges, And Automatic Balancing Devices (AREA)
- Measurement Of Current Or Voltage (AREA)
Abstract
706,571. Electric transformers. FERRANTI, Ltd. July 18, 1952 [Aug. 1, 1951], No. 18251/51. Class 38 (2). [Also in Group XXXVI] An instrument for measuring the A.C. leakage or difference current of a two-wire circuit comprises a two part magnetic core adapted to be separated, and brought together into a closed magnetic circuit about the go and return conductors a secondary winding on the core whose output is rectified and applied to a D.C. ammeter indicating the difference or leakage current, and a spring-loaded locating device determining the position of the current-carrying conductors within the magnetic circuit. The magnetic circuit comprises two laminated L-shaped members 1, 2 enclosing the insulated go and return conductors 21, 22; member 2 being fixed to the instrument body 4 and handle 5, Fig. 1, while the member 1 is mounted on a lever 6 pivoted at 7 and controlled by a trigger 8 to open and close the magnetic circuit against the spring 9. A secondary winding is distributed in four insulated and protected sections 16, 17, 18, 19 distributed on corresponding limbs of the magnetic circuit, which sections are series connected, Fig. 3, to a half-way rectifier 20 in series with a microammeter 12 normally shunted by protective push-switches 13, 14 and a calibrated resistance 15, whereby opening switch 13 causes the instrument to reach a lower range and opening switch 14 causes it to reach a higher range of the difference or leakage current in the conductors while when both switches are closed the instrument is shortcircuited for safety. The conductors 21, 22 are clamped in a fixed position against winding 16 by a spring loaded plunger 23 working between guides 24, 25 to form a locating recess, and the plunger may be recessed to receive the conductors. The major portion of the secondary winding may be concentrated on the fixed limb of the magnetic circuit opposite that against which the conductors are pressed by the plunger, and the meter may be energized from a fullwave rectifier supplied by the secondary.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB1825151A GB706571A (en) | 1951-08-01 | 1951-08-01 | An improved device for measuring electric currents |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB1825151A GB706571A (en) | 1951-08-01 | 1951-08-01 | An improved device for measuring electric currents |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB706571A true GB706571A (en) | 1954-03-31 |
Family
ID=10109254
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB1825151A Expired GB706571A (en) | 1951-08-01 | 1951-08-01 | An improved device for measuring electric currents |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB706571A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2137358A (en) * | 1980-07-16 | 1984-10-03 | Kokusai Denshin Denwa Co Ltd | Cable catching apparatus for use in locating submarine cables |
| GB2259780A (en) * | 1991-09-20 | 1993-03-24 | Michael Barry Watson | Sensing electric currents |
| CN110441581A (en) * | 2019-07-16 | 2019-11-12 | 上海北堃电力科技有限公司 | A kind of power grid bus current measuring device |
-
1951
- 1951-08-01 GB GB1825151A patent/GB706571A/en not_active Expired
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2137358A (en) * | 1980-07-16 | 1984-10-03 | Kokusai Denshin Denwa Co Ltd | Cable catching apparatus for use in locating submarine cables |
| GB2259780A (en) * | 1991-09-20 | 1993-03-24 | Michael Barry Watson | Sensing electric currents |
| CN110441581A (en) * | 2019-07-16 | 2019-11-12 | 上海北堃电力科技有限公司 | A kind of power grid bus current measuring device |
| CN110441581B (en) * | 2019-07-16 | 2023-12-29 | 上海北堃电力科技有限公司 | Power grid bus current measuring device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| ES8302963A1 (en) | Low voltage circuit breaker with adjustable hybrid triggering. | |
| GB880238A (en) | Protective arrangements for electric circuits and apparatus | |
| US4071824A (en) | Shrouded jaws for hook-on type instruments | |
| GB706571A (en) | An improved device for measuring electric currents | |
| US3274489A (en) | Cable fault locator for ungrounded electrical systems including means for applying a square wave to the cable under test | |
| JPS5730971A (en) | Metal detector | |
| FR2381384A1 (en) | Tester for conductance of electromechanical contact - has transformer secondary winding which can be short circuited by contact | |
| GB966443A (en) | Improvements in multi-range hook-on electrical indicating instrument | |
| US2513794A (en) | Method of testing electric cables | |
| JPS5542090A (en) | Safety checking device | |
| FR2383517A1 (en) | Holding relay with high sensitivity for low currents - has spring with knife edge near armature with axes at given angles | |
| GB327837A (en) | Improvements in or relating to electric current transformers and measuring instruments | |
| ES462711A1 (en) | Winding inspector | |
| GB592468A (en) | Improvements in earth leakage trip devices for electric circuits | |
| FR2317658A1 (en) | Current measuring probe with magnetic circuit in two parts - has coil into which conductor is inserted and held by spring clips | |
| US2689331A (en) | Apparatus for testing electromagnetic fields | |
| GB576708A (en) | Apparatus for detecting faults in electric cables | |
| SU109081A1 (en) | Instrument for checking the hardness of steel parts | |
| FR2316672A1 (en) | Vehicle break-in detector system - uses variation of magnetic field near to electrical conductor whose current varies | |
| GB1524793A (en) | Voltage probe for the measurement of interference voltage | |
| GB885418A (en) | Electric tong test devices | |
| JPS5748662A (en) | Large current measuring device | |
| GB918004A (en) | Improvements in electrical insulation testers | |
| GB608188A (en) | Improvements relating to a.c. measuring instruments | |
| GB1152793A (en) | Improvements in and relating to Earth Leakage Protection Devices |