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Tips for selecting relays

Relays from Magnecraft & Struthers-Dunn come in a variety of shapes, sizes, and ratings including socket or DIN-rail mountable versions. Capacitive loads want to remain at constant voltage. When the contacts are closed, a current surge can weld the contacts together. Inductive loads want to keep a constant current. When relay contacts open, the voltage surges to keep the current constant. This surge causes arcing across the contacts. Programmable logic controllers (PLCs) and computer-based controllers are great for handling logic and data-collection tasks for industrial controls. But when it comes to
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Products & Services
Reed Relays
Reed relays are electrically-operated switching devices that consist of two thin, magnetic strips (reeds) encapsulated in a glass envelope. They are used to switch industrial components such as solenoids, contactors and starter motors.
Solid State Relays
Solid state relays (SSR) or semiconductor relays are semiconductor devices that can be used in place of mechanical relays to switch electricity to a load in many applications.
High Voltage Relays
High voltage relays are used to transfer power for high voltage and high frequency applications. They are heavily insulated and consist of strong materials to increase contact life.
Thyristor Surge Suppressors
Thyristor surge suppressors are semiconductor chips used to protect circuits and devices from over-voltage and over-current.
Product Announcements
Schmersal Inc. - Safety Relays and Controllers
Safety controllers are designed to increase the level of safety in machine guarding and/or E-stop control circuits. They feature redundant, dual channel, cross monitoring logic circuits. These... (read more)
Comus International - Reed Relays from Comus International
A Reed relay consist of a reed switch and coil fitting into a housing which could be plastic, metal or moulded. Reed relays generally have a faster response time than electro-mechanical relays, lower... (read more)
Automationdirect.com - Motor Speed/Standstill Safety Relays
AutomationDirect BH5932 series safety speed relay modules ($279) provide standstill and overspeed monitoring of three-phase motors. LH5946 series safety relays ($349) provide standstill detection on... (read more)
PHD, Inc. - Solid state inductive sensing technology
High reliability, ease of mounting, and suitable for plant environments that are conductive to creating difficulties for electromechanical and other types of switches. (read more)
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