Gravity Digital 5A Relay Module

The Gravity relay module from DFRobot switches a load via the contact of a relay, controlled by a digital output of a microcontroller such as Arduino, ESP32 or Raspberry Pi. The control side is connected via the 3-pin Gravity connector, the load via screw terminals with NO, NC and COM. The relay picks up when the control input is HIGH, an LED shows the state.

Important: For safety reasons, the module is only intended for voltages up to 30 V and not for mains voltage, the back of the board is not insulated. The ratings 10A 250VAC apply to the relay, not to the module. The module is therefore not suitable for switching the mains supply of devices such as a 3D printer.

Note: The connection cable can be converted to male pins with a Dupont cable M-M, so that it also fits an Arduino UNO.

Recommended alternative for 3.3 V boards, recommended by DFRobot for 3.3 V systems: Gravity 16A Relay Module 3.3-5V Logic Compatible

Recommended Accessories:

• Dupont Cables M-M 10cm 20 Pieces
• Gravity IO Expansion Shield for Arduino V7.1

Features:

• 1 relay with 3 contacts (changeover): NO, NC, COM
• High-level control: the relay picks up when input D is HIGH
• Input D via 1 kΩ to a transistor, without optocoupler (DFRobot schematic V4.0)
• Status LED for the switching state
• Screw terminals for connecting the load
• 4 mounting holes

Application Examples:

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

Connection to 5 V Logic (for example Arduino UNO):

• + to 5V
• - to GND
• D to a digital output, for example pin 3
• Output HIGH: relay picked up, NO connected to COM. Output LOW: relay released, NC connected to COM

Connection to 3.3 V Logic (for example ESP32, Raspberry Pi):

• + to 5 V, the relay coil needs 5 V (Raspberry Pi: pin 2)
• - to GND (Raspberry Pi: pin 6)
• D to a GPIO (Raspberry Pi: GPIO17, pin 11). The input leads via 1 kΩ to the transistor and does not apply 5 V to the GPIO
• GPIO HIGH: relay on. GPIO LOW: relay off
• DFRobot states a switching threshold of 2.4 V and recommends a relay module with 3.3 V control for 3.3 V systems, see alternative above

Documentation:

• Wiki DFRobot DFR0017
• Example code for Arduino (DFRobot wiki)
• Schematic (PDF)
• Datasheet relay JQC-3FF (PDF)

Technical Data:

• Manufacturer: DFRobot
• Manufacturer SKU: DFR0017
• Permitted voltage on this module: up to 30 V
• Relay: Hongfa JQC-3FF, coil 5 V (version V4.0 according to DFRobot); the wiki names Omron G5LA for older versions
• Rated current of the relay according to DFRobot: 10 A (NO), 5 A (NC)
• Switching voltage of the relay according to DFRobot: 150 V AC / 24 V DC, maximum 250 V AC / 30 V DC
• Relay coil current: about 70 mA at 5 V (coil 70 Ω, JQC-3FF datasheet)
• Control signal: TTL, 0 to 0.4 V off, 2.4 to 5 V on
• Switching time: operate 10 ms, release 5 ms
• Connections: Gravity PH2.0 3-pin (D, +, -), screw terminals NC, NO, COM and one free terminal N/A
• Dimensions: 38 × 33 × 20 mm
• Weight: 25 g

Scope of Delivery:

• 1× Gravity Digital 5A Relay Module
• 1× Gravity digital sensor cable 3-pin, PH2.0 to Dupont socket, 30 cm