How do you use a SPDT relay?

A SPDT relay configuration switches one common pole to two other poles, flipping between them. Consider a SPDT relay with a common pole ‘C’ and let the other two poles be ‘A’ and ‘B’ respectively. When the coil is not powered(inactive), the common pole’ C’ is connected to the pole ‘A'(NC) and is in resting position.

How many pins are present in the SPDT relay?

i) Single Pole Single Throw (SPST) – Such relay has 4 terminal pins which consists of a pair of coil pins and a pair of pins which can be made connected or disconnected by activating or deactivating the relay. Such relay can categorized into normally open or normally closed type.

What is a 12VDC SPDT relay?

Description: This is a high quality single pole, double throw (SPDT) sealed relay from Omron. Use them to switch high voltage, and/or high current devices. The coil voltage on this relay is rated at 12VDC, and the load current is rated up to 10A.

What is SPDT relay contact?

SPDT (Single-Pole Double-Throw) relays have a single set of Form C, break before make or transfer contacts. That is, a common terminal connects to either of two others, never connecting to both at the same time. Including two for the coil, such a relay has a total of five terminals.

How relay is connected in circuit?

Relays control one electrical circuit by opening and closing contacts in another circuit. As relay diagrams show, when a relay contact is normally open (NO), there is an open contact when the relay is not energized. When a relay contact is Normally Closed (NC), there is a closed contact when the relay is not energized.

Which relay is double throw?

The DPDT relay (Double Pole Double Throw) is quite interesting and can be used in various scenarious, including for changing the direction of a motor as you can see in the picture below.

What is the difference between SPST and SPDT relay?

SPST simply mean single pole, single throw. The product controls one circuit with one On position. SPDT means that it is a single pole double throw which means it has two ON positions. DPST again means it controls two separate circuits but it only has one On position.

How many volts does a DPDT relay need?

Since the relay is rated for 12V, it should receive 12 volts in order to power on. It may work with less voltage, but 12V is really what it should receive. This goes into either side of the COIL terminals. Even if you switched the positive and negative voltage of the power supply, it should work exactly the same.

Why does polarity matter in a SPDT relay?

COIL – This is the other end of the coil. These are the terminals where you apply voltage to in order to give power to the coils (which then will close the switch). Polarity does not matter. One side gets positive voltage and the other side gets negative voltage. Polarity only matters if a diode is used. NO – This is Normally Open switch.

How to connect a single pole double throw relay?

In order to know how to connect a single pole double throw (SPDT) relay, you must know what each pin terminal represents and how the relay works. A Single Pole Double Throw Relay comes with five terminal points. The terminals are COIL, COIL, COM, and NO, and NC. This correlates to the following in the relay:

Where does continuity occur in a DPDT relay?

COM – This is the common of the relay. If the relay is powered and the switch is closed, COM and NO have continuity. If the relay isn’t powered and the switch is open, COM and NC have continuity. This is the terminal of the relay where you connect the first part of your circuit to.