- Order number: NCD-PR8-20
- Manufacturer product ID: PR8-20
This I2C 4-channel low-power signal relay controller offers a cross-platform solution with unmatched compatibility and expansion capabilities. Compatible with every IoT technology that supports I2C communications, this is the most versatile relay controller we have ever manufactured. All NCD I2C relay controllers have a I2C output, allowing you to chain together more relay controllers, a vast array of sensors, current monitors, PWM drivers, and much more. The expansion abilities of this relay board are unmatched by any other manufacturer in the world. On-board SPDT relays are ideally suited for low-power signal switching applications, up to 1 Amp at 12VDC. NCD SPDT relay controllers have three connection terminals for user-access to each relay. We use high-quality Omron relays with a low on-resistance between contacts. Designed primarily for resistive or mildly capacitive low-power signals, the on-board relays in this design focus on signal integrity, making it an ideal choice for telecommunications and low-power audio switching applications.
This controller is based on the MCP23008, a common I2C interface chip for GPIO applications. In this design, the GPIO port is used to control 4 on-board SPDT relays. Four programmable Digital Input/Output port pins are also available via screw terminals for use in Contact Closure detection applications or monitor and control external TTL circuits. Three on-board address jumpers allow up to 8 similar devices (based on the MCP23008 or MCP23017) to be chained to the same I2C bus for individual control. On-board status LEDs display the on/off status of each relay. This controller may be powered using our optional power supply or with 12VDC and direct screw terminal connection of bare power wires. Each relay is accessible to the user via screw terminals, capable of accepting 14 AWG wire.
What is the NCD I2C Interface?
NCD is the creator of plug and play modular hardware using the NCD I2C Interface connector standard. NCD I2C devices allow you to chain together several devices on the I2C bus, and communicate to each device individually at high speed (subject to the limitations of I2C). The NCD I2C Interface uses a standard 4-Pin I2C Input and I2C Output connector. NCD I2C devices communicate 5V I2C data and provides 5V DC power through this connector. NCD I2C devices use standard I2C communications for all data transport, which is supported by nearly every microcontroller in production today. The NCD I2C Interface is strictly a 5V standard, which is ideal for transport across longer cables. NCD I2C devices always include a 6″ (152mm) 4-conductor I2C cable. NCD I2C Mini Modules always include a 3″ (76mm) 4-conductor I2C cable. Cables and connectors are available separately for designers who would like to include their own NCD I2C Interface into their designs.
Plug and Play Connectivity
NCD I2C devices will plug in to any available NCD I2C Output. This includes just about everything we make in the NCD IoT Category, including all NCD IoT devices. We also manufacture a wide range of I2C adapters that make it easy to plug NCD I2C Devices directly into most computing platforms. The NCD I2C Interface adapters are available for Arduino, Banana Pi, BeagleBone, Bluz, C.H.I.P., ESP8266, Onion Omega, Particle Photon and Electron, PyCom, Raspberry Pi, 2, 3, and Zero, and Windows. We are always working to add new platform support for NCD I2C devices. NCD I2C Interface devices are compatible with just about everything in the microcontroller industry.
Unlimited I2C Expansion
Based on our plug-and-play I2C interface standard, all NCD I2C devices are equipped with a I2C output port, making it easy to expand to a wide variety of sensors, current monitors, relay controllers, PWM controllers, and much more! We are always designing new expansions for our modular plug-and-play I2C framework. We are dedicated to building a product line of interconnected devices to simplify all forms of automation. Re-use or upgrade your hardware in seconds by selecting the modules that best fit your needs, and chaining them together using the included I2C expansion cables!
Powering NCD I2C Interface Devices
Some NCD I2C devices require a external power supply, others may be powered through the 4-Pin I2C bus connector at 5VDC, and other devices are jumper selectable between external and I2C bus power. All I2C mini modules are powered through the 5V I2C bus connector, greatly simplifying connectivity.
1-Amp SPDT Signal Relay
This controller uses a 1-Amp small signal relay, allowing control of low-power telecommunications signals up to 12VDC at 1 Amp. Ideal for audio, telecommunications, and very low power switching applications. This relay has a low On resistance. The 1-Amp signal relay is of the SPDT variety, which provides Common (C), Normally Open (NO), and Normally Closed (NC) connections. Common is connected to NC when the relay is off. Common disconnects from NC and connects to NO when the relay is activated. All connections are made via screw terminals, capable of accepting up to 16 AWG wire.
Features
- 4-Channel SPDT Telecommunications Relay Controller
- 4-Channel Programmable Digital Input/Output
- Ideal for use with PC using Windows 8/10 via USB
- ESP8266 and USB I2C Interface Modules are Also Available
- Compatible with Arduino, Raspberry Pi, Onion, PyCom
- Switch Low-Power Signals up to 1 Amp at 12VDC or 120VAC
- MCP23008 I2C Controlled SPDT Low-Power Signal Relays
- I2C Output Port for Adding Sensors, Controllers, or More Relays
- Wireless Remote Operation with Key Fob Expansion Option
- Use the Arduino Wire Language to Control Relays using I2C Bus
- Example Libraries Available on GitHub
- Do you have any questions concerning this product?
- Mechanical Relay Types
- Controlling Inductive Devices: Managing Induction & Electromagnetic Interference
- Introduction to Computer Controlled Relays and Switching
- Relay Logic
- MCP23008.pdf
- I2C Connection Diagram.pdf
- MCP23008_8-Channel
- AnyI2C
- Official Repository
- Further products by NCD