Relay Module (1 Channel)

A Relay is a digital switch to control much higher voltages and currents than your normal Arduino boards does. When inputs a logic voltage, the relay will switch to allow current to flow or cutoff, depending on your wiring. A Relay usually consists of a coil, 1 common terminal, 1 normally closed terminal and one normally open terminal. When the coil is energized, the common terminal and the normally open terminal will have continuity.

Why do we want to use a relay and do we really need to? Anytime you want to switch on/off a device which draws more current or works with a high voltage, you’ll need to use a relay, such as controlling of headlights, parking lights, horns, etc.

Description

The module allows to control the actuators consuming the current up to 15 A with microcontroller’s ports or with any implementation set (including Arduino).

For proper operation, it is sufficient to connect the power of the relay and the digital control signal. Leads are the standard strip goldpin with pitch 2.54 mm which enable to connect via connecting cables.

Specifications

• The supply voltage VCC: 5 V
• High Input voltage trigger or Low Input voltage trigger (According to your choice)
• On-board LED to indicate the working status
• Coil voltage: 5 V
• The maximum voltage of contacts: 250 VAC, 125 VDC*
• Maximum current:
  • 10 A for  250 VAC
  • 15 A for 125 VAC
• Tile sizes 43 x17 mm

Examples of application

• Driver of lighting
• The driver of actuators
• Switch for electric devices, including motors

Connection

The module has four input / output VCC, GND, IN. To work correctly, you must connect the power supply 5 V to the VCC pin, mass GND and the input signal IN. Indicating the low state (the potential of the mass) switches the relay contacts. Disabling the IN lead or indicating the high position, switches the relay to its initial state.

Providing low state, switches the contacts of relay and makes the connection between the COM (the middle contact) and NO, seperates COM and NC. This operation is also signaled the illumination of the green led.