A protection relay shuts off a machine operating in a way that represents a potential risk to itself.
These devices supervise the operation of a machine or other installation by measuring current, voltage or phase variations. It shuts off the machine, cuts off power to an installation or triggers an alarm when a parameter exceeds authorized thresholds.
As with other relays, electromechanical models exist, though most now are semiconductor-based solid state relays. Some are directly programmable and are in ISO cases for rail installation.
Choice of a protection relay depends on the monitored parameters: overcurrent, zero velocity, excessive speed, current consumption, leaks, etc.
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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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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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Motor protection relay Tsubakimoto Chain
With the simple wiring system, this current-detecting overload protection...
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Motor protection relay 24 - 230 V AC | ETM CROUZET
- Controls temperature of machines using built-in PTC probes - Line break...
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The RED range is an earth leakage protection device offer with a built-in recloser. The automatic resetting function allows reclosing of the earth leakage protection...
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Feeder protection relay 40 - 264 V | 857 Allen Bradley
Bulletin 857 Motor-Feeder Protection, Medium Voltage offers solutions for today’s motor and feeder protection requirements...
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Voltage and frequency protection relay P94x Alstom Grid
MiCOM Alstom P94x voltage and frequency management relays provide an integrated solution for the secure and efficient operations of power systems. The MiCOM Alstom P94x series of voltage and frequency relays are capable of highly versatile applications and are easily integrated into both new and existing network control...
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Motor protection relay max. 250 A | Z Eaton Moeller
Bimetal relays Z Overload Relays Z overload relays offer motor protection in the event of single phasing or overload. Their auxiliary contacts disconnect...
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Motor protection relay CH/E series Eaton Count Control Products
Eaton's Motor Relays provide complete and reliable motor protection for any size motor at different voltage levels including monitoring and starting control functions. CH-Series CH-Series Eaton's CH-Series...
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Over-current, motor and overload protection relay max. 500 V, 1 - 160 A | SAO series OMRON
Solid-state, Plug-in Current Sensor Applicable to motor overcurrent protection and 3-phase...
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Overload protection relay 0.2 - 220 A | J7TKN Omron Europe
Thermal overload relays for J7 contactors J7TKN relays protect motors against...
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Overload protection relay TeSys LG/LJ Schneider Electric - Automation and Control
thermal overload...
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Medium voltage motor protection relay 857 series ROCKWELL AUTOMATION
Bulletin 857 Motor-Feeder Protection, Medium Voltage offers solutions for todays motor and feeder protection requirements in...
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Motor protection relay FANOX ELECTRONIC
Fanox PBM system guarantees perfects management function to installed motors The easy understanding of the gathering information by the PBM system makes the devices an unique tool for the maintainance department...
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In the machine- and plantbuilding sector the safety becomes more and more important. Everywhere, safety modules and also safety control systems are used. Despite the increasing use of semiconductor relays, the electromechanical...
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PCB safety relay 25 series Werner Electric GmbH
25 Series - PC Board Relays Keywords: Relays, board mounting relay, Power relays, blade relay, 2 C/O relay, 3 C/O relay, industrial automation relay, UL Approved relays, 25 series relays, werner relay contact material WERNER`s 25 Series PC Board Relays are the product of your choice if your designs require SPDT or even DPDT abilities but...
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Over-current and short-circuit protection relay KIW series Alfred Kuhse GmbH
The KIW current monitor monitors the current in a 3-phase network. It has 2 limit value relays for which the threshold values can be set independently in the range from 0.2 A to 20 A for the 5A version and from 0.04 A to 4 A for the 1A version. A separate time delay can be set for each limit value. The switching behaviour...
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Motor protection relay MPA Series Motorguardian™ Marsh Bellofram
The MPA series MotorGuardian™ from the ATC Diversified Electronics division of Marsh Bellofram is a microprocessor-based overload relay with set point security, designed to serve as a cost-effective added safeguard for the monitoring and performance management of three-phase AC motors, motor control packages and industrial pumps. The uniquely extensive functionality of the MPA series MotorGuardian™...
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Generator protection relay 12 - 120 V | PGR-4300 series Littelfuse
The PGR-4300 generator ground-fault relay provides a simple method for alarming a ground-fault condition on generators without the need...
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Over-current, motor and overload protection relay Iskra Sistemi
- A three-pole relay used with mini contactors - Used for overload protection of motors with operational currents up to 14 A and operational...
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Under-voltage and overvoltage protection relay CGV 24N/C CG Power Systems
UNDER-OVER VOLTAGE & NEUTRAL DISPLAY RELAY Product Overview The 'CGV 24C' Numerical Protection Relay is a fully digital relay based on microprocessor technology with...
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Under-voltage and overvoltage protection relay 6 - 300 V, 15 - 460 Hz | VME420 series BENDER
The voltage relays of the VME420 series are designed to monitor the frequency, undervoltage, overvoltage and the voltage between two threshold values (window...
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Under-voltage and overvoltage protection relay 8 A, 250 V | HRN-54, HRN-54N ETI
Over/undervoltage monitoring relay HRN-54, HRN-54N Advantages - Serves to monitor voltage , phase failure and sequence in switchboards, protection of devices in 3-phase mains - 1-module, DIN rail...
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Overload protection relay 112 - 800 A | CWM WEG
Description WEG’s three-pole contactors present high technology and safety, and easy installation. Main Features - Easy...
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Network protection relay 3x20 A,4x300 V | POM2-3243 PONOVO POWER CO., LTD
Three phase relay testing system POM2-3243 can test all types of protective relays. This relay tester has in-built output monitoring and recording function and also supports testing...
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Medium voltage overcurrent protection relay MPRB series CIRCUTOR
The MPRB relay and MPTA transformers represent a three-phase protection system that protects transformers and medium voltage distribution...
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PCB safety relay 3 A, 6 - 220 V | GEMO TEC AUTOMATISMES
Security relays 4 contacts / GEMO Relay conforming to EN50205 standard regarding relays "with linked contacts". No...
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Under-voltage and overvoltage protection relay max. 300 V KLASCHKA Industrieelektronik
Monitors voltages in DC or AC circuits for deviations above or below...
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Under-voltage and overvoltage protection relay 600VPR SELEC Controls Pvt. Ltd.
Voltage Protection Relay : 600VPR - 17.5mm DIN Rail - 3ø...
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Motor protection relay 28 V DC, 250 V AC, 0.1 – 10 A | 2-6500 series E-T-A
Bimetal operated single pole motor protection controls with automatic...
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Protection relay for 3-phase motors DMPU CARLO GAVAZZI
Main technical features • Measured voltages : up to 690V (external VT optional) • Measured currents :...
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PCB safety relay RE series EMAS
RE Series Endustrial Relays › PA6.6 Base head delay body › Wide label field for code spelling › 35 mm rail assmbly widh 8 and 11 pins socket › Test buttons and control indicator › Special body desing and contact tips assuring quick and faultless assembly -------------------------------------------------------------------------------- RS Series Relay an...
