RSAW PRC-023-2_2013_v1.2
... Each Transmission Owner, Generator Owner, and Distribution Provider shall use any one of the following criteria (Requirement R1, criteria 1 through 13) for any specific circuit terminal to prevent its phase protective relay settings from limiting transmission system loadability while maintaining rel ...
... Each Transmission Owner, Generator Owner, and Distribution Provider shall use any one of the following criteria (Requirement R1, criteria 1 through 13) for any specific circuit terminal to prevent its phase protective relay settings from limiting transmission system loadability while maintaining rel ...
Technical Information Relay Classification Electromechanical Relays
... This unique relay construction maximizes electrical and permanent magnet energy. A high-efficiency magnet adds to the magnetic flux of the relay coil, which also allows for tighter packing of relay parts. Relays having such a coil are known as “polarized relays.” Details of construction are shown be ...
... This unique relay construction maximizes electrical and permanent magnet energy. A high-efficiency magnet adds to the magnetic flux of the relay coil, which also allows for tighter packing of relay parts. Relays having such a coil are known as “polarized relays.” Details of construction are shown be ...
Current transformer selection guide
... If the ambient temperature around the CT exceeds 40 °C, the rated CT current must be higher than the Ips multiplied by the de-rating factor for the cubicle. (see binder B, chapter 1, topic 1). For a transformer differential protection, the rated currents of the two CT sets must be inversely proporti ...
... If the ambient temperature around the CT exceeds 40 °C, the rated CT current must be higher than the Ips multiplied by the de-rating factor for the cubicle. (see binder B, chapter 1, topic 1). For a transformer differential protection, the rated currents of the two CT sets must be inversely proporti ...
Topics in Circuit Protection For Power Supplies
... A point not often considered is the action of the fuses or MCB can be different during normal operational conditions versus those start-up conditions. When in normal operation a fault (short circuit) is more easily detected by a fuse or MCB because the Power Supply has sufficient over capacity to pr ...
... A point not often considered is the action of the fuses or MCB can be different during normal operational conditions versus those start-up conditions. When in normal operation a fault (short circuit) is more easily detected by a fuse or MCB because the Power Supply has sufficient over capacity to pr ...
Research on the Differential Protection Algorithm of Multi
... For on-load-tap-changing transformer, the transient response of primary and second voltage or current is according to location information of taps. Conventional differential protection is to set voltage and current’s change brought by variable ratio as unbalanced current for starting protection, and ...
... For on-load-tap-changing transformer, the transient response of primary and second voltage or current is according to location information of taps. Conventional differential protection is to set voltage and current’s change brought by variable ratio as unbalanced current for starting protection, and ...
neutral grounding
... (typically 50 amps or more), in order to operate protective fault-clearing relays and current transformers. These devices are then able to quickly clear the fault, usually within a few seconds. This fast response time is important, since it limits damage to equipment, prevents additional faults from ...
... (typically 50 amps or more), in order to operate protective fault-clearing relays and current transformers. These devices are then able to quickly clear the fault, usually within a few seconds. This fast response time is important, since it limits damage to equipment, prevents additional faults from ...
A Method to Enhance Ground
... HORT circuit faults in a power system include single line-to-ground (SLG), line-to-line (LL), double line-to-ground (DLG), and three-phase short-circuit (3SC). Among these types of faults, the SLG occurs most often while the 3SC is commonly deemed the most severe one with largest magnitude of fault ...
... HORT circuit faults in a power system include single line-to-ground (SLG), line-to-line (LL), double line-to-ground (DLG), and three-phase short-circuit (3SC). Among these types of faults, the SLG occurs most often while the 3SC is commonly deemed the most severe one with largest magnitude of fault ...
section 264313 - surge protection for low
... This Product MasterSpec Section is licensed by ARCOM to SSI, an ILSCO Company ("Licensee"). This Product MasterSpec Section modifies the original MasterSpec text, and does not include the full content of the original MasterSpec Section. Revisions made to the original MasterSpec text are made solely ...
... This Product MasterSpec Section is licensed by ARCOM to SSI, an ILSCO Company ("Licensee"). This Product MasterSpec Section modifies the original MasterSpec text, and does not include the full content of the original MasterSpec Section. Revisions made to the original MasterSpec text are made solely ...
Earthing Transformer
... neutral of the system is not grounded, it is possible for high voltages to appear from line to ground during normal switching of a circuit having a line to ground fault. These voltages may cause failure of insulation at other locations on the system and result to damage to equipment. A ground fault ...
... neutral of the system is not grounded, it is possible for high voltages to appear from line to ground during normal switching of a circuit having a line to ground fault. These voltages may cause failure of insulation at other locations on the system and result to damage to equipment. A ground fault ...
Definition of Relay Terminology
... signal and reflected (wave) signal. V.S.W.R. refers to the ratio of the maximum value to minimum value of the waveform. The V.S.W.R. is 1 when there is no reflected wave. It usually becomes greater than 1. ...
... signal and reflected (wave) signal. V.S.W.R. refers to the ratio of the maximum value to minimum value of the waveform. The V.S.W.R. is 1 when there is no reflected wave. It usually becomes greater than 1. ...
Dorman Smith
... A comprehensive range of meter relays offering measurement, monitoring and control of any electrical or process parameter. Relays combine a highly accurate indicator with high and low set points, which operate alarm and control circuits when the monitored signal value deviates from the set point lim ...
... A comprehensive range of meter relays offering measurement, monitoring and control of any electrical or process parameter. Relays combine a highly accurate indicator with high and low set points, which operate alarm and control circuits when the monitored signal value deviates from the set point lim ...
A magnetic pick-up and release system for moving
... timing accuracy nor high repetition rates were particularly important. Although the response time of the relay is of the order of 15 ms, this is still much shorter than the sample pick-up time, typically 50 ms. We were fortunate to have almost all the components available in our ‘box of spares’ and ...
... timing accuracy nor high repetition rates were particularly important. Although the response time of the relay is of the order of 15 ms, this is still much shorter than the sample pick-up time, typically 50 ms. We were fortunate to have almost all the components available in our ‘box of spares’ and ...
Electrical Control and Ladder Diagrams
... between the electrical contacts and the switch below the contacts. Consider the left-hand contact point a hinge; the switch rotates counterclockwise up when actuated. The NC symbols develop a gap when the switch lifts. The limit switch is drawn on both the electrical and fluid power diagrams, becaus ...
... between the electrical contacts and the switch below the contacts. Consider the left-hand contact point a hinge; the switch rotates counterclockwise up when actuated. The NC symbols develop a gap when the switch lifts. The limit switch is drawn on both the electrical and fluid power diagrams, becaus ...
Personal Protective Equipment Manual Appendix B: Table 8
... Hair enclosures are required for long hair (longer than four inches), which can be drawn into machine parts such as chains, belts rotating devices, suction devices, and blowers. Hair may even be drawn into machines guarded with mesh. It may also present an ignition risk in areas near open flames or ...
... Hair enclosures are required for long hair (longer than four inches), which can be drawn into machine parts such as chains, belts rotating devices, suction devices, and blowers. Hair may even be drawn into machines guarded with mesh. It may also present an ignition risk in areas near open flames or ...
Protective relay
In electrical engineering, a protective relay is a device designed to trip a circuit breaker when a fault is detected. The first protective relays were electromagnetic devices, relying on coils operating on moving parts to provide detection of abnormal operating conditions such as over-current, over-voltage, reverse power flow, over- and under- frequency. Microprocessor-based digital protection relays now emulate the original devices, as well as providing types of protection and supervision impractical with electromechanical relays. In many cases a single microprocessor relay provides functions that would take two or more electromechanical devices. By combining several functions in one case, numerical relays also save capital cost and maintenance cost over electromechanical relays. However, due to their very long life span, tens of thousands of these ""silent sentinels"" are still protecting transmission lines and electrical apparatus all over the world. An important transmission line or generator unit will have cubicles dedicated to protection, with many individual electromechanical devices, or one or two microprocessor relays.The theory and application of these protective devices is an important part of the education of an electrical engineer who specializes in power systems. The need to act quickly to protect circuits and equipment as well as the general public often requires protective relays to respond and trip a breaker within a few thousandths of a second. In these cases it is critical that the protective relays are properly maintained and regularly tested.