Relays
This is an eight channel 5V DC relay module with active low. It can be controlled by variety of microcontrollers such as Arduino, Raspberry Pi, PIC, DSP, AVR or ARM etc.
- Has the ability to control eight separate appliances or pieces of equipment
- Eight on-board optoisolators enable direct interfacing to microcontrollers
- Eight red LED status lights on-board show relay activity
- Widely used in PLC control or smart home control
- 4 x M3 mounting holes for easy fixing via standoffs
- 15-20mA drive current needed per channel
- Relay coil maximum operating voltage: 5V
- Relay coil maximum current: 89.3mA
- Relay contact maximum: AC250V at 10A or DC30V at 10A
- No. of relays/channels: 8
- Item size: 134 x 55 x 20mm
- Item weight: 116g
- 1 x 8 Channel Relay Module
Warning
Exercise proper caution when connecting mains driven equipment or appliances to relay module as lethal current will be present.
Use this relay board with your Arduino, Raspberry Pi or your custom micro-controller projects!
Specifications:- Each Relay has LED indication when ON
- SPDT Relays with terminal block outputs.
- Relay Coil voltage: 5 VDC
- Power Requirement: 5 VDC
- 10A 250V AC / 10A 30V DC
- 1 x Four channel 5V DC Relay Module
This is a two channel 5V DC relay module with active low. It can be controlled by variety of microcontrollers such as Arduino, Raspberry Pi, PIC, DSP, AVR or ARM etc.
- Has the ability to control two separate appliances or pieces of equipment
- Two on-board optoisolators enable direct interfacing to microcontrollers.
- Two red LED status lights on-board show relay activity.
- Widely used in PLC control or smart home control
- 4 x M3 mounting holes for easy fixing via standoffs
- 15-20mA drive current needed per channel
- Relay coil maximum operating voltage: 5V
- Relay coil maximum current: 89.3mA
- Relay contact maximum: AC250V at 10A or DC30V at 10A
- No. of relays/channels: 2
- Item size: 57 x 55 x 20mm
- Item weight: 57g
- 1 x 2 Channel Relay Module
Warning
Exercise proper caution when connecting mains driven equipment or appliances to relay module as lethal current will be present.
The GSM Gate Opener RTU5024 is a powerful GSM relay that can be used for authorized door access, controlling gates, switching of remote equipment, and car parking systems. Additionally, it can also be used in places that require you to turn on/off your system, machines, or equipment remotely with a free call from your mobile phone.
The four-channel relay module contains four 5V relays and the associated switching and isolating components, which makes interfacing with a microcontroller or sensor easy with minimum components and connections.
A solid state relay (SSR) is an electronic switching device that switches on or off when an external voltage (AC or DC) is applied across its control terminals. It serves the same function as an electromechanical relay, but has no moving parts and therefore results in a longer operational lifetime.
Specifications:
5V Omron solid state relays 240V / 2A, output with resistive fuse 240V / 2A.
Dimensions: 57x55x25 (length x width x height)
Input Power: 5VDC
Control signal input voltage: (0-2.5V low state relay ON) (3-5V state high relay OFF)
Voltage:5V
Quiescent current: 0 mA
Operating current: 12.5mA
Trigger Voltage: 3.3-5V
Trigger current: 2mA
CH2: relay module signal triggering end (high to trigger active)
CH3: relay module signal triggering end (high to trigger active)
CH4: relay module signal triggering end (high to trigger active)
Package includes:
1 x Four way Solid State Relay Module
Python Code
The four-channel relay module contains four 5V relays and the associated switching and isolating components, which makes interfacing with a microcontroller or sensor easy with minimum components and connections.
A solid state relay (SSR) is an electronic switching device that switches on or off when an external voltage (AC or DC) is applied across its control terminals. It serves the same function as an electromechanical relay, but has no moving parts and therefore results in a longer operational lifetime.
Feature:
Voltage:5V
Quiescent current: 0 mA
Operating current: 12.5mA
Trigger Voltage: 3.3-5V
Trigger current: 2mA
Package included:
1 x One way Solid State Relay Module
Relay tutorial for Raspberry Pi
It is a learning code wireless remote control switch (receiver), the output way /working way can be changed as you like. It is easy to match the transmitter. 4 Relays which can make the equipment turn or reverse, on/off. The volume is small and the performance is stable and reliable, with high receive sensitivity.
Features:
1. It covers application ranging from simple domestic remote control to autonomous control, like auto door, window, lifting equipment, entrance access, up and down controller, alarm system industrial control and security etc.
2. These remote controls are designed to control a wide variety of electronic devices with a wireless signal.
3. Extremely easy to set up and use.
4. Compatible with 2262 / 2260 / 1527 / 2240 etc chip and several code wireless remote control. So it can meet someone's need of choosing the wireless remote control as they like to work with it .
Instructions:
1. Press the learning code, the indicator flash, loosen your finger, press any button of the remote control, the indicator flash 2 times and off, it means you learn it successfully .
2. It can learn more than 12 PCS 2262 or 1527 chip with the different code wireless remote control.
3. remove/clean: press the learning button about 8 seconds , the indicator turn on to off, it means the information that you keep have been removed successfully.
Output working way:
1. Self-lock: connect the JP1 with the cutting out cap.
2. Jog: the cutting-out cap is non-occupation, JP1 and JP2 do not connect either.
3. Inter-lock: Connect the Jp2 with the Cutting out cap,
Jog: press one button is ON, loosen your finger on the same button is OFF (need one channel switch and one buttons remote control).
Self -lock: press one button for one time is ON, press the same button again is OFF (need one channel switch and one buttons remote control).
Inter-lock: press one button is ON, press another button is OFF (need one channel switch and 2 buttons remote control).
Receiver:
1. Working voltage: DC12V
2. Quiescent condition: Less than 6mA
3. Working temperature: -40°c 80°c
4. Receiver sensitivity: more than -105dBm
5. Working frequency: 433mhz
6. Output voltage: DC and AC is optional
7. Output current: Less than 3A
8. Max load current: 10A
9. Dimensions: 72 x 52 x 26mm
Remote control transmitter:
1. Remote Distance: 200M
2. Operating Voltage: DC 12V
3. Frequency: 433mhz
4. Operating Current: 13 mAh
5. Code Type: Fixed code / Learning code
6. Dimensions: 58 x 39 x 14mm
Relay ratings:
DC 14V 20A or AC 125V 20A
Package included:
2 x Transimitter
1 x Receiver
Description:
The MonkMakes Relay for micro:bit is a solid-state (no moving parts) relay that allows an output of a micro:bit to turn things on and off.
A micro:bit can turn an LED on and off directly, but anything more powerful requires something like a relay or a transistor. Using a transistor to switch something on and off requires a shared ground connection with the micro:bit and a knowledge electronics that you or your students may not be ready for. The MonkMakes Relay for micro:bit is much easier to use, acting like a simple micro:bit controlled switch.
This relay can be used to switch low voltage devices such as light bulbs, a motor, a small heating element or even a string of 12V LED lighting. The voltage needs to be kept under 16V, but the relay will automatically protect itself against too much current.
FEATURES
- Solid-sate relay (up to 2 Amps)
- Active LED indicator
- Resettable ‘polyfuse’ to protect against over-current
Getting Started
Connecting your micro:bit
The Relay requires just two connections to the micro:bit. One to GND (ground) and one to whatever pin is to be used to control the relay’s switching action.
When attaching the alligator clips to the micro:bit, make sure that the clips are perpendicular to the board so that they are not touching any of the neighbouring connectors on the micro:Bit edge connector.
Here’s an example of how you could wire up a MonkMakes Relay for micro:bit to turn an old fashioned light bulb on and off.
HEX File
The quickest way to try out your relay is to DOWNLOAD THIS HEX FILE >and then copy it onto your micro:bit. The program will turn the relay on and off once a second.
JavaScript Blocks Editor
Set the controlling pin to 1 and the relay contacts will close, set it to 0 and the contacts will open again. Its as simple as that. So, to make your relay turn on and off once a second, open the Blocks Editor, add a forever block and then the digital write blocks from the pins category and the pauses from the basic category.
MicroPython
Paste the following code into the Python window and then Download the file and copy it onto your your micro:bit.
from microbit import *
while True:
pin0.write_digital(True)
sleep(500)
pin0.write_digital(False)
sleep(500)
Analog Outputs
The latest MonkMakes Relay for micro:bit can do more than just switch things on and off. It can also be used with micro:bit analog outputs. Look closely at your Relay for micro:bit and is it has the version number v1ev (under the word ‘Board’) then it can be used with the ‘analog write’ block in the blocks editor or the ‘write_analog’ function in MicroPython. If your board has the version number v1e then it is not suitable for use with analog outputs – sorry you were unlucky to get one of the small batch of first boards to be sold.
The output of the Relay for micro:bit is not linear at low PWM and high PWM values as the following chart illustrates.
The y-axis shows the current in mA for a test load resistor supplied from a constant voltage source. The x-axis is the analog write value (0 to 1023). As you can see, there is a dead zone up to a analog output value of about 100, followed by a relatively good linear region right up to about 1000, after which the output effectively becomes ‘on’.
The tests were carried out at the default PWM frequency of 50Hz for the micro:bit. Lower frequency PWM is expected to produce more linear results.
The module uses a quality relay with a normally open interface
Using SMD optocoupler isolation, driving ability, stable performance
The module can be set high or low with a jumper setting trigger
Fault-tolerant design, even if the control line is broken, the relay will not operate
A power indicator (green) and a relay status indicator (red)
Specification:
- Maximum load: AC 250V/10A, DC 30V/10A
- Trigger current: 5mA
- Working voltage: 5V
- Module size: 50mm x 26mm x 18.5mm (L x W x H)
Four mounting bolt holes, diameter 3.1mm
Module interface:
DC : positive power supply (VCC)
DC-: negative power supply (GND)
IN: can be high or low level to control the relay
Relay outputs:
NO: normally open
COM: Common Interface
NC: normally closed
High and low level trigger options:
It is low level trigger when jumper connects to LOW pin
It is high level trigger when jumper connects to HIGH pin
What's in the box:
1 x 1 Channel H/L level trigger optocoupler relay module
Interfacing with a relay
Non-Latching relay can be used in a number of applications including home equipment, vending machines and OA equipment. The miniature relay is often referred to as the “ice cube” relay due to the relays size and shape. Pre-soldered terminals, high switching power up to 10 A, PCB terminals and flux protection are among many of the included benefits of this relay.
Features:
Simple relay magnetic circuit to meet low cost of mass production
Specifications:
Model: SRD-5VDC-SL-C
Coil voltage: DC 5V
Coil resistance: 70Ω ~ 80Ω
Contact resistance: 100Ω Max
Operation time: 10msec Max
Release time: 5msec Max
Ambient temperature: -25°C to 70°C
Operating humidity: 45 to 85%RH
Operating current: 43mA ~ 46mA
Release current: 15mA ~ 18mA
Pin: 5Pin
Insulation resistance: ≥100M (Ohm)
Dielectric strength:
Between coil & contacts: AC 1500V 50HZ ~ 60HZ/min
Between contacts: AC 1000V 50HZ ~ 60HZ/min
Rated load:: 10A 250V AC / 10A 125V AC / 10A 30V DC / 10A 28V DC
Size: 1.8 x 1.5 x 1.6cm (L x W x H)
Package includes:
1 x SRD-5VDC-SL-C 5V Power Relay
When the soil moisture is lower than preferred setting, the relay will automatically pull in, start the sprinkler, water pump etc. until the moister reaches the desired humidity level and automatically stop.
Product use: Through the potentiometer, adjust to the desired soil moisture level
Specifications:
Electrical parameters: Supply voltage: 12VDC
Input current: more than 100mA Relay Load Max: 10A 250V AC or 10A 30V DC
Module instruction:
1 sensors applied to the detection of soil moisture; Module
2. Blue potentiometer is used to adjust soil moisture level, clockwise adjustment and control the humidity will be bigger, counterclockwise smaller; 3. Due to module delay function, adjust the humidity value, wait about 5-8 seconds, see if the the relay state changed, the green LED lamp will also have corresponding change, until adjusted to meet the requirements.
Package Includes:
1 x Soil moisture control module
1 x Soil sensor
2 x 20cm long DuPont lines
Based on infrared technology, automatically control products, when someone enters switch sensing range, pir detect changes in the human body infrared spectrum, switch automatically switches the load, do not leave the sensing range (who are active), the switch will continue to be on.
Person leaves, switch off automatically load delay.
Convenient and saves energy.
Specifications:
1. Bipolar design: three-wire connection, and the load capacity 100W
2. Automatic sensors: switch immediately turned on with delay off after you leave.
3. Relay switch: can withstand high current output, high power load.
4. Adjustable delay time: 10 seconds -350 seconds
5. Ultra Low Power: Switch own power <0.0088W/h (annual power consumption of <0.077 degrees)
6. Induction: Passive
7. Operating Voltage: DC 12V
7. Inductive mode: passive infrared pyroelectric
6. Quiescent Current: 50uA
7. Sensing Distance: 3 to 5m
8. Load Capacity: Maximum: 100W
9. Induction Angle: About 120°, 100 ° up and down
10. Load Range: Various types of DC LED lamps, load
11. Ambient Temperature: -20 to 50℃
12. Output Mode: Relay control output DC 12V high level / low level
13. Size: 45 x 30mm, PIR lens diameter: 12mm
Wiring instructions:
Red wire: Power input 12V
Black wire: Power output -12V
Yellow wire: OUT 12V power output
Package includes:
1 x DC 12V PIR IR Sensor Module Relay
Bistable relays are used to switch electrical circuits by impulse command, especially for lighting control in ordinary applications.
Reduce power consumption over extended duration's. A latching relay is a two-position electrically actuated switch that maintains either contact position indefinitely without any power being sent to the coil and is a perfect choice to reduce the power consumption of a system.
Specifications:
Working voltage: DC 5V
Working current: 70MA
Standby current: 1UA
Load current: AC 250V / 10A, DC 30V / 10A
Trigger mode: Low pulse trigger
Size: 35mm x 16mm x 18.5mm
Weight: 13.5 g
USE 1:
By default, the relay is released, press the trigger button, the relay pull, press again, the relay release, the third press, the relay pull, and so on.
USE 2:
By default, the relay is released, MCU output low-pulse(0.3-1seconds), the relay pull, low-pulse again, the relay release, the third low-pulse, the relay pull, and so on.
Module interface:
1. VCC: positive power supply (VCC)
2. GND: negative power supply (GND)
3. T: Low pulse trigger
Relay outputs:
1. NO: normally open relay interface
2. COM: Common Interface Relays
3. NC: normally closed relay interface
Typical applications:
Automotive electronics
Motor
LED
Smart Home
Emergency lighting
MCU development board
Toy car
Package includes:
1 x Relay module
What's in the box?
1 x Relay
1 x Grove connector
Industrial 8-Channel Relay Module For Raspberry Pi Pico, Power Supply Isolation, Photocoupler Isolation
Description:
Embedded Protections: Power Supply Isolation & Photocoupler Isolation
Features:
- Onboard unibody power supply isolation, provides stable isolated voltage, needs no extra power supply for the isolated terminal
- Onboard photocoupler isolation, prevent interference from external high-voltage circuit connected to the relay
- High quality relay, contact rating: 10A 250V AC or ≤10A 30V DC
- ABS protection enclosure with rail-mount support, easy to install, safe to use
- Breakout USB port and BOOT pin, make it easy to debug without disassembling the enclosure
- PWR indicator, RGB LED, and passive buzzer outside the enclosure
- Comes with development resources and manual (Raspberry Pi Pico C/C and MicroPython examples)
Specifications:
OPERATING VOLTAGE | - 5V | RELAY CHANNEL | - 8 ch |
---|---|---|---|
COMMUNICATION PROTOCOL | - USB | CONTACT FORM | - 1NO 1NC |
COMMUNICATION INTERFACE | - Micro USB |
What's in the box?
- ABS protection enclosure (top and bottom) x1
- Pico-Relay-B x1
- Screwdriver x1
- Screws pack x1


- Raspberry Pi Pico header
- Relay screw terminal
for connecting external devices - Power supply screw terminal
the multi relays are connected in parallel - Pogo pins
- USB communication port
connected via pogo pins - BOOT key
connected via pogo pins - Reset key
Pico reset - Passive buzzer
controllable sound frequency
- Power indicator
- WS2812
RGB LED, cool! - 8-channel quality relays
contact rating per channel: ≤10A 250V AC or ≤10A 30V DC - Relay operating indicator
- Photocoupler isolation
prevent interference from external high-voltage circuit connected to the relay - Power supply isolation
provides stable isolated voltage, needs no extra power supply for the isolated terminal - Thickened tracks
allows large current devices

Outline dimensions

The MonkMakes SSR is a low voltage solid state relay (no moving parts). This makes it super-easy to control loads of up to 2A at 16V from an Arduino, Raspberry Pi or other 3 or 5V microcontroller or single board computer.
This modern take on the electro-mechanical relay can even be used for low frequency PWM to control the power to its load.
Specifications:
This relay can be used to switch low voltage devices such as light bulbs, a motor, a small heating element or even a string of 12V LED lighting. The voltage needs to be kept under 16V, but the relay will automatically protect itself against too much current.
• Solid-sate relay up to 2 Amp Peak 1A continuous AC/DC
• Active LED indicator
• Resettable ‘polyfuse’ to protect against over-current
• Great for Arduino and Raspberry Pi
• Suitable for low frequency PWM

What's in the box ?
1 x Monkmakes SSR board
Resources:
Datasheet(PDF)

(* ONLY SSR -Solid State Relay - Included - all other products are for reference use only*)
Industrial 6-ch Relay Module for Raspberry Pi Zero, RS485/CAN, Isolated Protections, Tailored For Raspberry Pi Zero Series also Suitable For Raspberry Pi Zero With Pre-Soldered Pin header.
Features:
- RS485 half-duplex communication: using SP3485, UART control, auto RX/TX switch
- CAN half-duplex communication: using MCP2515 SN65HVD230 solution, SPI control
- Onboard unibody power supply isolation, provides stable isolated voltage, needs no extra power supply for the isolated terminal
- Onboard photocoupler isolation, prevent interference from external high-voltage circuit connected to the relay
- Onboard TVS (Transient Voltage Suppressor), effectively suppress surge voltage and transient spike voltage in the circuit, lightningproof & anti-electrostatic
- Onboard resettable fuses and protection diodes, ensuring current/voltage stable output, preventing over current/voltage, better shock-resistance performance
- High quality relay, contact rating: ≤10A 250V AC or ≤10A 30V DC
- ABS protection enclosure with rail-mount support, easy to install, safe to use
- Comes with development resources and manual (wiringPi and python examples)
Specifications:
OPERATING VOLTAGE | 7V~36V (industrial input voltage compatible) | RELAY CHANNEL | 6 ch |
---|---|---|---|
COMMUNICATION PROTOCOL | RS485, CAN | CONTACT FORM | 1NO 1NC |
What's in the box ?
1 x ABS protection enclosure (top and bottom)
1 x RPi Zero Relay
1 x Screwdriver
1 x 12V 1A power adapter
1 x Screws pack
Resources :
WIKI: RPi_Zero_Relay




Description:
The RPi Relay Board gives your Pi the ability to control high voltage/high current devices, easily makes normal home appliances become intelligent.
RPi Relay Board Features- Supports Raspberry Pi A /B /2B/3B
- High quality relays, loads up to 250VAC/5A, 30VDC/5A
- Photo coupling isolation, prevent interference from high voltage circuit
- Onboard LEDs for indicating relays status
- Relay control jumper, allows to control the relays by custom pins other than the default pins
- Comes with development resources, including examples in wiringPi, WebioPi, shell, python, and bcm2835

What's on the RPi Relay Board

- Raspberry Pi GPIO interface: for connecting Raspberry Pi
- Relay screw terminal: for connecting target devices
- Relays
- Photocoupler: PC817
- Relay indicator
- LED on: relay NC is opened, NO is closed
- LED off: relay NC is closed, NO is opened
- Power indicator
- Relay control jumper
- short the jumper: control the relays by default I/Os used in the example code
- open the jumper: control the relays by custom I/Os through jumper wires
Development Resources
Wiki : www.waveshare.com/wiki/RPi_Relay_Board
Package Includes:
- RPi Relay Board x 1
- RPi screws pack (2pcs) x 1
Overview
The RPi Relay Board (B) is an expansion board with 8-ch relays for Raspberry Pi. It gives your Pi the ability to control high voltage products such as home appliances.
Features- Supports Raspberry Pi A /B /2B/3B/3B /4B
- High quality relays, loads up to 5A 250V AC or 5A 30V DC
- Photo coupling isolation, prevent interference from high voltage circuit
- Standard rail mount bottom case
- Onboard LEDs for indicating relays status
- Relay control pin selection jumper, allows to control the relays by custom pins other than the default pins
- Reserved control Interface, allows to work with controllers like PLC
- Comes with development resources, including examples in wiringPi, bcm2835, python, python-bottle (webpage control), and crontab (cron job)
- Power supply voltage: 5V
- Trigger signal: 3.3V/5V
- Relay channels: 8-ch
- Contact form: SPDT-NO,NC
- Closed current: 6mA (per channel)
- Connector: screw terminal block
- Dimension: 232 × 72 (mm)
- Mounting hole size: 3.0mm

Size | 62mm(L)x44mm(W)x23mm(H) |
Input Voltage (Trigger) | DC 3-32V |
Output Voltage(Line) | AC 24-380V |
Output Current(Line) | 50 A |
On Voltage | ≤1V |
On-Off Time | ≤10ms |
Off Leakage Current | ≤2mA |
Transparent Lid Included | Yes |
Package Includes:
1 X 50A SSR-50DA Solid State Relay With Cover
Datasheet available at https://cdn.sparkfun.com/datasheets/Components/General/SSR40DA.pdf
Depending on how hard your relay works, you might want to add a heat sink to it.
Q:During continuity testing with my multimeter why does my relay on the AC side not switch on?
A: The below info was found at http://www.crydom.com/en/tech/newsletters/solid statements - bench test an ssr.pdf
A multimeter determines impedance by injecting a small amount of voltage through it's probes into the circuit being tested. It then measures the current flowing through the probes and calculates resistance. Easy enough; Resistance = Voltage / Current! However, as we just discussed above, a solid state relay’s output turns on by “stealing” a bit of voltage from the AC mains in order to supply current to the gate of the SCRs. Simply put, if the AC mains is not connected to the relay then the output cannot turn on. Since the voltage and current produced by a multimeter is not sufficient enough to turn on the SCRs, the output of a solid state relay will remain in the off state; even with the input signal applied. As a result, SSRs will sometimes fail an incoming inspection because the engineer expects to see a significant change in the output impedance when they turn on the relay.The most effective way to bench test a solid state relay is to construct a simple test circuit consisting of a DC power supply or battery (a 9Vdc battery will work fine in most cases ) and a 60W or 100W light bulb.