Relay Module 24V (1 Channel) Active Low Level Trigger

Key Features of Relay Module 24V X 1 Relay:

• Single relay
• Switch AC up to 125/250VAC @ 10A
• Switch DC up to 30VDC @ 10A
• Coil Voltage: 24V
• Normally Open (NO) and Normally Closed (NC) contacts
• LED indicator when relay is energized
• Tile sizes 43 x17 mm

Relay modules are handy for controlling external loads.  Unlike transistors used for switching, relays use metallic switch contacts which avoids the power loss and heating inherent in transistor switching circuits.  They are also  nicely contained little modules that are simple to hook-up and are especially useful for switching AC.  The main downside is that being an electro-mechanical device, like any mechanical switch relays are more prone to wear and tear over prolonged use.

Relay Operation

The output of the relay is rated to switch up to 30VDC at 10A per the relay markings (see our notes below) or up to 125/250VAC at up to 10A.

The output is SPDT type with both a NO (Normally Open) terminal and a NC (Normally Closed) terminal relative to the center unmarked common (COM) terminal.

Note:  Some modules have the relay outputs labeled in Chinese, but the NO/NC connections are the same as shown here.

Module Connections

1 x 3 Header

• GND = Connect to ground of the power supply
• IN1 = The control end, the driving current should be more than 4mA (Active Low)
• Vcc = Connect to power supply

Relay Contacts

• NC = Normally Closed side of the relay
• Center Terminal = Common terminal usually connects to the load power source
• NO = Normally Open side of the relay