Morley AIS 02 - Fire Detection Systems Guide
... voltage for a few milliseconds, and looks for the line voltage being held up by the capacitor. When a head is removed, the panel will see the line voltage drop immediately as the capacitor's discharge will be inhibited by the diode, and thereby a fault can be signalled. A third type of end of line d ...
... voltage for a few milliseconds, and looks for the line voltage being held up by the capacitor. When a head is removed, the panel will see the line voltage drop immediately as the capacitor's discharge will be inhibited by the diode, and thereby a fault can be signalled. A third type of end of line d ...
Slide 1
... • Consider an alarm system as shown. • It can be design in 2 ways • Both ways work exactly in the same manner • The second design however gives fail save design. • Murphy’s law is true. If something can go wrong it will. ...
... • Consider an alarm system as shown. • It can be design in 2 ways • Both ways work exactly in the same manner • The second design however gives fail save design. • Murphy’s law is true. If something can go wrong it will. ...
G7L-2A-X DC24 Datasheet
... failure mode is failure to break the circuit. In a worst-case scenario, burning may extend to surrounding components. Do not use these Relays outside of the specified ratings and service life, or for any application other than high DC voltages. Implement safety circuits and other safety measures to ...
... failure mode is failure to break the circuit. In a worst-case scenario, burning may extend to surrounding components. Do not use these Relays outside of the specified ratings and service life, or for any application other than high DC voltages. Implement safety circuits and other safety measures to ...
FA295564 - Schneider Electric
... condition). It is easy to test this scenario: you can inject V1, V2, and V3 in a normal phase angle with nominal values but swap V1 and V2, or any other pair of voltages, at relay terminals. Let’s assume you set voltage sensors and 47 protection on Sepam as below: ...
... condition). It is easy to test this scenario: you can inject V1, V2, and V3 in a normal phase angle with nominal values but swap V1 and V2, or any other pair of voltages, at relay terminals. Let’s assume you set voltage sensors and 47 protection on Sepam as below: ...
Digital Low-Impedance Bus Differential Protection
... CTs are required to have a low secondary leakage impedance (completely distributed windings or toroidal coils). During external faults, even with severe saturation of some of the CTs, the voltage does not rise above certain level, because the other CTs will provide a lower-impedance path as compared ...
... CTs are required to have a low secondary leakage impedance (completely distributed windings or toroidal coils). During external faults, even with severe saturation of some of the CTs, the voltage does not rise above certain level, because the other CTs will provide a lower-impedance path as compared ...
Selection Guide
... PolyTron PTC Device Selection 1) Determine circuit parameters: a. Normal operating current – Ihold b. Maximum circuit voltage – Vmax c. Ambient operating temperature – °C d. Maximum fault current – Imax ...
... PolyTron PTC Device Selection 1) Determine circuit parameters: a. Normal operating current – Ihold b. Maximum circuit voltage – Vmax c. Ambient operating temperature – °C d. Maximum fault current – Imax ...
5.0 Starter Motors
... Many other relays are available, some need a signal to be sent from an E.C.U. for them to operate. Some operate on a time basis i.e. interior light delay, and some have their own integrated circuit built into them i.e. electronic relays. The two types of relay used most often are the four pin switch ...
... Many other relays are available, some need a signal to be sent from an E.C.U. for them to operate. Some operate on a time basis i.e. interior light delay, and some have their own integrated circuit built into them i.e. electronic relays. The two types of relay used most often are the four pin switch ...
micom P342 / 343 / 344 / 345
... Interturn (split phase) differential (P343/4/5 only) On generators with multi-turn coils and two or more windings per phase, such as hydrogenerators, interturn (split phase) differential may be used to detect turn to turn faults. The element operates as a definite time overcurrent function with inde ...
... Interturn (split phase) differential (P343/4/5 only) On generators with multi-turn coils and two or more windings per phase, such as hydrogenerators, interturn (split phase) differential may be used to detect turn to turn faults. The element operates as a definite time overcurrent function with inde ...
Fundamentals and Improvements for Directional Relays
... windings. In the center was a magnetic core with a movable cup with contacts and a spring to provide reset tension. The relay was designed such that no rotational movement or torque occurred when the magnetic fluxes of the two coils were in phase [1]. ...
... windings. In the center was a magnetic core with a movable cup with contacts and a spring to provide reset tension. The relay was designed such that no rotational movement or torque occurred when the magnetic fluxes of the two coils were in phase [1]. ...
3. Basic requirements for the Digital Protective Relay
... 3.4.3 Separation of different kinds of cables (power, power supply, auxiliary, data, measures) 3.4.4 Use of equipotential metallic structure for cable trays 3.4.5 Use of screened cables for data and measure 3.4.6 A power supply protection (filtering, over voltage protection) 3.4.7 Equipment and inst ...
... 3.4.3 Separation of different kinds of cables (power, power supply, auxiliary, data, measures) 3.4.4 Use of equipotential metallic structure for cable trays 3.4.5 Use of screened cables for data and measure 3.4.6 A power supply protection (filtering, over voltage protection) 3.4.7 Equipment and inst ...
Smartwired Switching System
... The work covered in this section is subject to all of the requirements in the General Conditions of the Specifications. Contractor shall coordinate all of the work in this section with all of the trades covered in other sections of the specification to provide a complete and operable system. ...
... The work covered in this section is subject to all of the requirements in the General Conditions of the Specifications. Contractor shall coordinate all of the work in this section with all of the trades covered in other sections of the specification to provide a complete and operable system. ...
Rast 5 Power Relay 419 EA
... Coil versions, AC coil Coil Rated Operate Release Coil code voltage voltage voltage resistance ...
... Coil versions, AC coil Coil Rated Operate Release Coil code voltage voltage voltage resistance ...
ELG3331: DESIGN OF LOGIC CIRCUIT Define the problem Write
... We translate the word statements into logic-like statements. Activate the relay if either or both switches are on. In such case, the output should be zero. This means that enough current (15 mA) will flow through the relay and RC. When both inputs are zero, the relay should not operate and the outpu ...
... We translate the word statements into logic-like statements. Activate the relay if either or both switches are on. In such case, the output should be zero. This means that enough current (15 mA) will flow through the relay and RC. When both inputs are zero, the relay should not operate and the outpu ...
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.