- Relays are most commonly used switching device in electronics.
- Before we proceed with the circuit to drive the relay we have to consider two important parameter of the relay.
- Trigger Voltage is the voltage required to turn on the relay that is to change the contact from Common->NC to Common->NO.
- The other parameter is your Load Voltage & Current.
- This is the amount of voltage or current that the NC,NO or Common terminal of the relay could withstand.
- In our case for DC it is maximum of 30V and 10A.
- Make sure the load you are using falls into this range.
- The above circuit shows a bare-minimum concept for a relay to operate.
- Since the relay has 5V trigger voltage we have used a +5V DC supply to one end of the coil and the other end to ground through a switch.
- This switch can be anything from a small transistor to a micro-controller or a microprocessor which can perform switching operating.
- You can also notice a diode connected across the coil of the relay, this diode is called the Fly back Diode.
- The purpose of the diode is to protect the switch from high voltage spike that can produced by the relay coil.
- As shown one end of the load can be connected to the Common pin and the other end is either connected to NO or NC.
- If connected to NO the load remains disconnected before trigger and if connected to NC the load remains connected before trigger.
- 1 X Relay 5V 5 Pin (Original)
|10A 250VAC/28VDC,10A 125VAC/28VDC|
Coil rated voltage
Coil pick-up voltage
Coil drop-out voltage
|-25 degrees Celsius to +70 degrees Celsius|
Coil and contacts
|Contact and contacts|| |
|Mounting form|| |
|Dimensions||1.9 × 1.54 × 1.5 cm|