GB790699A - Improvements in protection apparatus for operating electric circuits with a variabletime lag - Google Patents
Improvements in protection apparatus for operating electric circuits with a variabletime lagInfo
- Publication number
- GB790699A GB790699A GB1856555A GB1856555A GB790699A GB 790699 A GB790699 A GB 790699A GB 1856555 A GB1856555 A GB 1856555A GB 1856555 A GB1856555 A GB 1856555A GB 790699 A GB790699 A GB 790699A
- Authority
- GB
- United Kingdom
- Prior art keywords
- coil
- contacts
- circuit
- time lag
- lag
- 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
-
- 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
- H02H3/08—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 responsive to excess current
- H02H3/093—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 responsive to excess current with timing means
Landscapes
- Emergency Protection Circuit Devices (AREA)
Abstract
790,699. Protective cut-out systems. BALDWIN, H. T. June 27, 1956 [June 28, 1955], No. 18565/55. Class 38 (5). A protective circuit with inverse time lag comprises current transformers A with secondary windings b in series and connected to a bridge rectifier C supplying relay coils c, c<SP>1</SP>. Coil c operates contacts d in the time-delay circuit comprising a capacitor d<SP>3</SP>, a resistance d<SP>4</SP> and a relay coil d<SP>1</SP> which together with the coil c<SP>1</SP> acts on contacts d<SP>2</SP> in the circuit of the supply contactor coil (not shown). When an isolator (not shown) on the " live " side of the contactor is closed, a potentiometer d<SP>6</SP> is energized to supply a bridge rectifier d<SP>5</SP> and the coil d<SP>1</SP> so as to close the contacts d<SP>2</SP>. When excess current flows in the current-transformer circuit the coil c opens the contacts d to de-energize the coil d' with a time lag. the time lag being reduced as the fault current increases by the action of the coil c<SP>1</SP> opposing coil d<SP>1</SP>.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB1856555A GB790699A (en) | 1955-06-28 | 1955-06-28 | Improvements in protection apparatus for operating electric circuits with a variabletime lag |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB1856555A GB790699A (en) | 1955-06-28 | 1955-06-28 | Improvements in protection apparatus for operating electric circuits with a variabletime lag |
Publications (1)
Publication Number | Publication Date |
---|---|
GB790699A true GB790699A (en) | 1958-02-12 |
Family
ID=10114638
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB1856555A Expired GB790699A (en) | 1955-06-28 | 1955-06-28 | Improvements in protection apparatus for operating electric circuits with a variabletime lag |
Country Status (1)
Country | Link |
---|---|
GB (1) | GB790699A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2081204A1 (en) * | 1970-03-17 | 1971-12-03 | Merlin Gerin |
-
1955
- 1955-06-28 GB GB1856555A patent/GB790699A/en not_active Expired
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2081204A1 (en) * | 1970-03-17 | 1971-12-03 | Merlin Gerin |
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