All the switch component mosfet scr triac igbt etc in the solid state relay only acts as a spst switch and there is no single component in the solid state relay that has the spdt function besides the opto coupler with optoelectronic isolation feature is used in the normal solid state relay as the signal transmission component so the input control circuit of the ssr switch is.
Spdt solid state relay schematic.
Relays are used where it is necessary to control a circuit by an independent low power signal.
A simple high current spdt solid state dc relay or a dc ssr can be constructed using a couple of mosfets and an optocoupler as shown in the digaram above.
A relay is an electrically operated switch it consists of a set of input terminals for a single or multiple control signals and a set of operating contact terminals the switch may have any number of contacts in multiple contact forms such as make contacts break contacts or combinations thereof.
So basically you can see the spdt relay as a way of switching between 2 circuits.
In this article we will briefly discuss the ssr solid state relay its construction operation schematics different types of ssr relays based on its switching property and input output forms we will also discuss the advantages disadvantages of solid state relay ssr comparing to electromagnetic.
Construction operation applications types of ssr relays.
Sp and dp refer to single pole and double pole st and dt refer to single throw and double throw.
When there is.
Pole refers to the number of circuits controlled by the switch.
What is solid state relay.
Mouser offers inventory pricing datasheets for spdt 1 form c solid state relays.
The single pole double throw spdt relay is quite useful in certain applications because of its internal configuration.
In an absence of an external trigger the lower mosfet stays switched off allowing the upper mosfet to conduct through the 10k resistor connected across the.
Relay is a electro mechanical switch used to control high power application through low power signal electronic circuits for an example a simple timer circuit working under 5v dc bias can not control high voltage light bulb by introducing relay component we can easily control light bulb.
Many relays use an electromagnet to mechanically operate a switch but other operating principles are also used such as solid state relays.
Sp switches control only one electrical circuit.
The idea looks self explanatory.
Dp switches control two independent circuits and act like two identical switches that are mechanically linked.
Typical relay typical relay contains electromagnetic coil n o contact n c contact and common contact.
It has one common terminal and 2 contacts in 2 different configurations.
Relays are used where it is necessary to control a circuit by a low power signal with complete electrical isolation between control and controlled circuits or where several circuits must be controlled.