GB1100647A - Improvements in or relating to high voltage circuit protection arrangements - Google Patents
Improvements in or relating to high voltage circuit protection arrangementsInfo
- Publication number
- GB1100647A GB1100647A GB1731265A GB1731265A GB1100647A GB 1100647 A GB1100647 A GB 1100647A GB 1731265 A GB1731265 A GB 1731265A GB 1731265 A GB1731265 A GB 1731265A GB 1100647 A GB1100647 A GB 1100647A
- Authority
- GB
- United Kingdom
- Prior art keywords
- output
- circuit
- gate
- pulse
- detector
- 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
- H02H1/00—Details of emergency protective circuit arrangements
- H02H1/0061—Details of emergency protective circuit arrangements concerning transmission of signals
- H02H1/0069—Details of emergency protective circuit arrangements concerning transmission of signals by means of light or heat rays
Landscapes
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Burglar Alarm Systems (AREA)
Abstract
1,100,647. Protective arrangements. MARCONI CO. Ltd. 29 Dec., 1965 [23 April, 1965], No. 17312/65. Heading H2K. [Also in Division G1] The fact that overload conditions are occurring in a high voltage line, is transmitted over a radiation link to alarm or safety apparatus, the radiation transmitter being fed by a pulse generator having an operating characteristic dependent on the line condition. In the line to be protected there is inserted a series resistance, the voltage drop across which controls the mark-space ratio of a blocking oscillator T. The oscillator output may be amplified and is applied to an infra-red source, e.g. a GaAs diode, the pulsed output from which is received at a low voltage station by a photo diode detector 10. The detector output is amplified and applied to a Schmidt trigger circuit 12 which passes only pulses above a predetermined amplitude, shaping those that are passed. Connected to the trigger circuit output is a timing circuit 13 (a one-shot multivibrator) and an AND gate 14. The timing circuit is triggered by the trailing edges of pulses from the Schmidt trigger. Under normal line conditions the transmitted pulses representing this condition are sufficiently spaced apart that a timing circuit pulse ends before the next pulse from trigger 12 (Fig. 2, not shown). However, if a voltage overload occurs, the mark-space ratio of the pulse generator rises substantially and a pulse from the Schmidt trigger coincides with a timing circuit pulse, producing an output from the AND gate to actuate the alarm. The device is also provided with a fail safe circuit connected to another output of the Schmidt trigger and providing one input to an OR gate 15, the other input of which is from the AND gate 14. An output from either the AND gate or the fail safe circuit is passed on to a resettable bistable circuit 17 which operates the alarm and/or safety means when over-load occurs. The fail safe circuit comprises a detector 16 and inverting amplifier 20 and gives an output when no pulses are obtained from the detector 10.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB1731265A GB1100647A (en) | 1965-04-23 | 1965-04-23 | Improvements in or relating to high voltage circuit protection arrangements |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB1731265A GB1100647A (en) | 1965-04-23 | 1965-04-23 | Improvements in or relating to high voltage circuit protection arrangements |
Publications (1)
Publication Number | Publication Date |
---|---|
GB1100647A true GB1100647A (en) | 1968-01-24 |
Family
ID=10092973
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB1731265A Expired GB1100647A (en) | 1965-04-23 | 1965-04-23 | Improvements in or relating to high voltage circuit protection arrangements |
Country Status (1)
Country | Link |
---|---|
GB (1) | GB1100647A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2131239A (en) * | 1982-09-10 | 1984-06-13 | Matsushita Electric Works Ltd | Current detecting device |
-
1965
- 1965-04-23 GB GB1731265A patent/GB1100647A/en not_active Expired
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2131239A (en) * | 1982-09-10 | 1984-06-13 | Matsushita Electric Works Ltd | Current detecting device |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
GB1462913A (en) | Dual spectrum infrared fire detection system with high energy ammunition round discrimination | |
US4135161A (en) | Method and means for pulse detection | |
GB1248300A (en) | Thunderstorm warning system | |
DK149726B (en) | SMOKE DETECTOR WITH IMPULSE EVALUATION CIRCUIT | |
GB1100647A (en) | Improvements in or relating to high voltage circuit protection arrangements | |
EP0375120A1 (en) | Nuclear event detectors | |
DE1791192A1 (en) | Device for the detection of unauthorized entry to protect a limited surveillance area | |
GB1181564A (en) | Self-Clocking Record Sensing System. | |
US3524984A (en) | Nuclear explosion detection systems | |
US3069624A (en) | Automatic power trip switch for a transmitter having high reflective power | |
GB1106805A (en) | Electronic protection apparatus | |
US2727143A (en) | Means for minmizing pulse reflections in linear delay lines loaded with a nonlinear load | |
GB1558471A (en) | Fire detectors | |
GB1185270A (en) | An Electrical Protection Circuit having a Preselected Current Time Characteristic | |
US3685587A (en) | Light responsive activating apparatus for fire or explosion suppressing systems | |
GB998337A (en) | Improvements in or relating to phase measuring circuits | |
SU1695518A1 (en) | Device for protection against impulse noise | |
KATADA et al. | Stilpnomelane co-existing with biotite in a Ryôke metamorphic rock | |
GB1137876A (en) | High voltage d.c. transmission systems with protection means | |
NESTERUK et al. | Contrast reception of a random-phase pulsed signal with correlated noise(Random-phase pulsed signal detection by contrast reception techniques against background of normal correlated noise) | |
BEARD | Status report on latest developments in clear air turbulence(Clear air turbulence detection and prediction by laser, radiometer, radar and other devices) | |
SIMOVSKAIA et al. | Distribution function for the product of envelopes of a mixture of Gaussian noise with a pulse signal in the case of N stored pulses(Distribution function for probability density of random process at output of multiplier acted upon by envelopes consisting of Gaussian noise and pulse signal) | |
FR1454342A (en) | Safety device acting in the event of an overload, usable in particular on plow bodies | |
KOONS | Proton precipitation by a whistler-mode wave from a VLF transmitter[Interim Report] | |
GOSTEV | Determination of the transfer functions of pulsed systems having a first-order link with both periodic and step-varying parameters(Transfer function of pulse amplitude modulated sampled data control systems with element generating arbitrarily shaped pulses and first order element series connected with constant parameter elements) |