What Are Relays?

A relay is an electrically controlled switch composed of an electromagnet that is assisted by a spring-loaded changeover contact. Implemented when high power or voltage circuits need to be used in tandem with a low voltage circuit, such components also make it possible for circuits to reach galvanic isolation when needed. When deciding between relays, it is imperative that the device being chosen fits your systems circuitry and requirements. To achieve optimal results for whatever your intended relay needs may be, we will discuss the importance of relay systems and their various operational considerations for your ease of procurement.

First applied to lengthy telephone lines, relay systems made it possible for weakened signals to be recharged when coming in contact with an intermediate station. Capable of revitalizing incoming signals for prolonged transmission, as there are countless relay systems intentionally manufactured for specific control functions, one must be sure that a compatible component is chosen. In general, relays can be found in a multitude of forms for a myriad of applications ranging from the following: coaxial relays, contactors, force-guided contact relays, latching relays, machine tool relays, multi-voltage relays, overload protection relays, solid-state relays, vacuum relays, and various other types.

As a variation of a switch, relays share pole and throw terminology to determine distinct contact forms and connections. When in operation, a relay can be activated to switch between one or more circuits, those of which are known as “poles.” Once a pole is switched, it is then viewed as “thrown,” and classified based on the number of contact points a specific relay contains. Utilized for electrical circuit relay switches and their differing functional aspects, relays can be commonly found in four primary types which are single-pole, single-throw; single-pole, double-throw; double-pole, single-throw; and double-pole, double-throw variations. Of these four types, relay switches can also be classified as normally open (NO) or normally closed (NC). Despite the aforementioned relay switch combinations, there are still a total of twenty-three variations of relay systems that exist to this date which can be used for a myriad of electrical assemblies.

Though relay systems are adept at switching between contact points within a circuit, parts assessed for installment must follow appropriate considerations before implementation. When inspecting a network for potential relay candidates, one must go over a checklist of factors to ensure all relay components of choice are actually a precise fit for a given application. These factors include, but are not limited to, number and type of contacts, contact sequence, contact current rating, contact voltage rating, operating lifetime, operational environment, regulatory approvals, and other various factors. As each switch is unique to a particular application, all precautionary measures should be taken to avoid exceeding a contact current's established value. Avoiding damage through the implementation of standard regulatory procedures, relay components can operate as intended for the benefit of the system.

To ensure your network connections and devices are accurately monitored and tracked, find what you need at NSN Components. We have all the electrical accessories you require to fit any one of your unique applications! As a dependable distributor of various relay types, relay sockets, relay coils, electronic circuits, and more, we invite you to browse our inventory for numerous industrial supplies and their applicable apparatuses. Due to our quality control and export compliance, we operate with AS9120B, ISO 9001:2015, and FAA AC 00-56B certification and accreditation. If you would like to request a quote for your comparisons, you can submit an RFQ form as provided on our website. Upon receipt, a dedicated account manager will quickly review and respond with a personalized solution to your needs in just 15 minutes or less, 24/7x365.