A relay is a control mechanism that activates or deactivates one or several parts of an electrical circuit. The two main categories are electromechanical and solid state relays.
These devices are used primarily to remotely switch a device or a circuit on or off. Remote electromechanical or electronic switching protects the user from possible danger associated with direct switch or contactor use, and makes possible automated switching. Some relays are used for security and protection. At activation thresholds, relays are used to control current, voltage, or a signal level. Time-delay relays exist as well.
Relays exist in mechanical form, with electromagnets moving contacts when energized. Normally open or normally closed relays change position when activated by an electrical signal. Compact, solid-state relays consist of semiconductors and have no moving parts.
Choice of a relay depends on intended use. For example, a time-delay relay is activated with a predetermined lapse after receiving a signal. Current strength must also be considered. Solid state relays cannot handle currents of the same strength as electromechanical models. On the other hand, solid state relays offer faster switching speeds.
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Generator protection relay REG630 IEC ABB Oy Distribution Automation
Relion® REG630 is a comprehensive generator management IED for protection, control, measuring and supervision of small and medium sized power generators. REG630 is a member of ABBs Relion® product family and a part of its 630 protection and control product series characterized by functional scalability and flexible configurability. REG630 also features necessary control functions required...
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Differential protection relay for two winding transformers 7UT85 SIEMENS Smart Grid
Two winding transformers 2 sides, 4 measurement points The transformer differential protection 7UT85 is a universal protection,...
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Centralized busbar protection relay B95 Plus GE Digital Energy
The Multilin™ B95Plus Bus Protection System is the ideal solution for one of the biggest challenges for large bus protection: the time and cost involved in the design, installation and commissioning of the field wiring between measurements from the switchyard and the bus relay in the control room. The HardFiber Brick, the environmentally...
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Relay with force guided contacts 6 A | 7S series FINDER France
Relay module with forcibly guided contacts For safety applications,...
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DIN-rail time delay relay 17.5 mm | Chronos 2 CROUZET
- Relay or solid state output - Multi-function or mono-function -...
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Electromechanical relay for PCB 12 / 12 VDC | H-550 HENGSTLER
Labelling H-550-1071 Drive System bistabil Voltage nominal 12 / 12 Coil Resistance 73 / 220 Normally Open Contact 0 Normally Closed Contact...
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Solid state relay SSRDIN Series OMEGA
Ratings Up to 30 A (22.5 mm), 45 A (45 mm), or 25 A 3-Phase LED Input Status Indicator Integral Heat Sink Eliminates the...
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Safety relay 24 VDC | MSI-RM2 LEUZE ELECTRONIC
Opto-electronic protective devices today frequently have electronic switching outputs and integrated additional functions such as contactor monitoring (EDM) and start/restart interlock. However the requirement for the protective...
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PNOZ X: PNOZ X safety relays are proven through their reliability and robustness. You'll find them used over a wide area in the most diverse safety applications. Use one PNOZ X per safety function. Its technical features are based on voltage-free, electromechanical contacts in 2 relay technology. Sizes vary from 22.5 to 90 mm, the number of contacts from two to eight. PNOZsigma: The new compact...
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Safety relay 24 VDC | QS90SR2SP MITSUBISHI ELECTRIC EUROPE
The QS90SR2SP safety relay module allows safety I/O to be included in a conventional System Q controller, for when it is not cost effective to specify a dedicated safety controller. The...
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Safety relay Cat. 4/PL, e/SIL 3, IP 40, IEC 60529 JOKAB SAFETY
Safety Relay We have the most flexible safety relays on the market. A universal relay is a safety relay with various input options for various safety devices and risk levels. Internally, the safety relay is of the...
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Line protection relay SIEMENS Low-Voltage & Products
Line Circuit Relays Overview Line circuit relays are used to interrupt circuits and prevent electromagnetic fields in circuits where there are currently no active loads. If the loads are disconnected, and the line circuit relay measures a usage of only 2 to 20 VA adjustable it disconnects the cable to the supply voltage...
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Multi-function safety relay 100 x 25 x 105 mm, IP20 | G1501S ifm electronic
Multifunctional with relay outputs suitable for your applications. E-stop with cross-fault monitoring and optional simultaneity monitoring. Connection of mechanical safety switches and fail-safe sensors. For clocked fail-safe sensors from ifm electronic. Two-hand control to EN 574, type IIIC, mechanical...
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Speed and stand-still monitoring relay max. 400 V | AZR31S1 series SCHMERSAL
Fail-safe standstill monitors Sensor-free detection of standstill by monitoring e.m.f. Direct connection to three-phase motors...
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Solid state relay 8 - 280 A | THYRITOP 20 CHAUVIN ARNOUX
Thyristor solid state relays for switching resistive loads from 8A to 280A, in single-phase. Direct drive by our STATOP temperature controllers. DIN rail...
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Solid state relay GEMS SENSORS & CONTROLS
Gems solid-state switching units perform the functions of electro-mechanical...
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Safety relay steute Schaltgeräte
SRM 21 RT2 Thermoplastic enclosure Control category 4 to EN 954-1 2 enabling...
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Motor protection relay Tsubakimoto Chain
With the simple wiring system, this current-detecting overload protection...
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Emergency stop relay Honeywell Sensing and Control
Description The FF-SRS5924 Emergency Stop Modules are designed...
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Trip relay KFD, KFU series PEPPERL & FUCHS
Trip amplifiers monitor limit values of temperatures, flows, levels,...
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Galvanically isolated electromechanical relay 1 - 2 channels, SIL 2 (IEC 61508) | 9172 series STAHL
I.S. Relay Module Series 9172 For binary signal...
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The degree of automation is very advanced in today's production engineering....
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Snap-action pneumatic relay max. 100 psig, 5 l/min Clippard
Input Psi: 3 to 100 psig / 0.2 to 7 bar...
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Magnetic Saftey Monitoring Systems System Operation : The correct operation of the system is ensured, as the circuitry monitors each sensor and magnet to ensure they are aligned correctly, by using an evaluation circuit...
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Safety relay SIRIUS 3SK1 Siemens Safety Integrated
Flexible Realization of Simple Safety Requirements with SIRIUS 3SK1 Safety Relays Are you looking for a rapid and easy way to realize safe systems? We have the solution: SIRIUS 3SK1 safety relays. The new safety relays...
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Speed and stand-still monitoring relay max. 690 V | MOC3ZA SICK
At a glance Standstill monitoring by means of residual voltage measurement 3 normally open and 1 normally closed positively guided safety contacts 2 application diagnostic outputs for...
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Transducer and relay module JUMPFLEX WAGO
The 6mm-wide WAGO isolation amplifiers and transducers share a common profile and can be easily commoned rather than requiring complex discrete wiring. The plug-in relays can easily be changed...
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Solid state relay for PCB max. 1 A | G3S/G3SD OMRON
Ultra-small, dual in-line package (DIP) SSR. Terminals compatible with G6B Electromagnetic Relays. Mix with G6Bs as the application...
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Relay with force guided contacts G7SA Omron Europe
Forcibly guided relay for socket or PCB-mounting The slim G7SA relay family with forcibly guided contacts is available as a four or...
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Solid state relay 1 A, max. 250 V AC, 3 - 60 V DC | AQ-C Panasonic Electric Works Europe AG
FEATURES 1. Space saving, Vertical size with a maximum thickness of 4.5 mm. Mounting space has been reduced to 30% (compared to conventional...
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Solid state relay Delphi Power Train
Delphi Solid State Relays (SSRs) provide variable load control through Pulse Width Modulation (PWM). They can be used to replace traditional electromechanical relays and fuses which are found in electrical centers and other devices. Because they are resettable, they provide the advantage of enabling maintenance-free circuit protection. Two versions are available: 10 Amp SSR for variable load...
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Contactor relay 220 VDC, 10 A | MK-S(X) OMRON Electronics
DC-switching Relay up to 220VDC, 10A(resistive load) The MK-S(X) is the smallest relay in the world that can switch 220VDC 10A resistive load....
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Safety relay ES4P series Eaton Moeller
The Easy family, consisting of theEasy Relay (control relay), Easy HMI (HMI systems) and Easy Control (compact PLCs), covers a large number of applications in the standard controller environment. The latest member of Easy the family – Easy Safety – offers an optimum solution for safety-related tasks, utilising at the same time the simplicity...
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Safety relay 20 ms, 24 VDC | QS90SR2SP MITSUBISHI Automation
The QS90SR2SP safety relay module allows safety I/O to be included in a conventional System Q controller, for when it is not cost effective to specify a dedicated safety controller. The module...
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Whether its safety switches or safety relays, BERNSTEIN has the complete range of products for your application. Our SCR safety relays are used to reliably evaluate signals, such as those generated by BERNSTEIN position switches, safety switches, safety latching devices, safety cable pull switches, safety sensors or 2-hand...
