Raspberry Pi 8-Channel Relay Module Expansion Board

The RPi Relay Board (B) from Waveshare is an expansion board with 8 relays for the Raspberry Pi. The Raspberry Pi is plugged onto the 40-pin header, and the loads are connected via screw terminals. Optocouplers isolate the control side from the relays. The board sits in a bottom case for mounting on a DIN rail.

Important: For safety reasons, the board is only intended for voltages up to 30 V and not for mains voltage. The rating 5 A 250 V AC applies to the individual relay, not to the board. The board is therefore not suitable for switching the mains supply of devices such as a 3D printer.

Recommended Accessories:

• Raspberry Pi 4 4G Model B (Cortex-A72)
• 12V Solenoid Valve DN15 1/2 Inch

Features:

• 8 relays, each with a changeover contact (NO, NC)
• Optocouplers between Raspberry Pi and relays
• Status LED for each relay
• Relay_JMP jumper for selecting the control pins, custom pins instead of the default pins possible
• Reserved control interface, for example for a PLC
• Bottom case for 35 mm DIN rail
• Example programs from Waveshare for wiringPi, bcm2835, Python, python-bottle (web control) and crontab

Application Examples:

• Switching 12 V solenoid valves for irrigation
• Switching LED strips with extra-low voltage on and off
• Controlling fans and pumps with extra-low voltage

Connection to the Raspberry Pi (3.3 V logic):

• Plug the Raspberry Pi onto the 40-pin header
• Leave the Relay_JMP jumper fitted
• Relays 1 to 8 on GPIO 5, 6, 13, 16, 19, 20, 21, 26 (BCM, pins 29, 31, 33, 36, 35, 38, 40, 37)
• The marking on the board corresponds to the BCM number
• GPIO LOW: relay on. GPIO HIGH: relay off

Connection to another controller (5 V logic):

• Without Raspberry Pi: remove the Relay_JMP jumper
• Control signals to the reserved control interface, control signal 3.3 V or 5 V according to Waveshare
• Check the pinout of the interface and the 5 V supply in the Waveshare Wiki before connecting

Documentation:

• Waveshare Wiki RPi Relay Board (B)
• Guide with pinout (Spotpear)

Technical Data:

• Manufacturer: Waveshare, SKU 15423
• Type: RPi Relay Board (B)
• Permitted voltage on this board: up to 30 V
• Rating of the individual relay according to Waveshare: AC 250 V / 5 A, DC 30 V / 5 A
• Contact: changeover (NO, NC)
• Supply voltage: 5 V
• Control signal: 3.3 V or 5 V
• Control current: 6 mA per channel
• Default control pins: GPIO 5, 6, 13, 16, 19, 20, 21, 26 (BCM)
• Control: LOW switches the relay on
• Load connection: screw terminals
• Compatible: Raspberry Pi with 40-pin header, for example A+, B+, 2B, 3B, 3B+, 4B
• Mounting hole diameter: 3.0 mm
• Dimensions: 232 × 72 mm
• Weight: 285 g

Scope of Delivery:

• 1× Raspberry Pi 8-channel relay module expansion board
• 1× bottom case for DIN rail
• 1× screw kit