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The RoHS icon on this product indicates that the PCBs, components, solder, and chemicals are all lead-free and RoHS compliant. Additionally, this product is produced using a lead-free process. Unfortunately, we are currently unable to provide documentation confirming that this product is RoHS compliant.
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Package Includes:
Notes:
- This board uses 4-pin connectors for I2C bus.
Features:
- PCF8574A I2C bus chips
- 100kHz I2C bus frequency
- Selectable I2C bus pull-up resistors
- Addressable via 3 jumpers, supporting up to 8 addresses
- Up to 16 boards on a single bus
- Compatible with most microcontrollers
- Supports microcontroller port with 2.5 to 5.5V logic
- 8 relay outputs
- 24Vdc coil voltages
- Relay contact rating: 0.5A @120Vac, 1A @30Vdc, 0.15A @48Vdc
- I2C operating voltage: 2.5Vdc to 5.5Vdc
- On-board reverse polarity protection circuits
- Small PCB size: 81.6x36.1mm
This is an I2C relay board, designed as a remote relay expander for the I2C bus. It is ideal for expanding relay outputs in compact spaces. The board is based on the PCF8574A, and each PCF8574 or PCF8574A board can be connected to a single bus, supporting up to 8 boards. A single bus can therefore support up to 16 boards when both PCF8574 and PCF8574A are used.
The board supports a 100kHz bus frequency and features selectable bus pull-up resistors for SDA and SCL signals. It is equipped with eight small relays, with coil input voltage selectable from either the bus voltage or an external voltage. The board includes inverse polarity protection circuits to prevent damage from incorrect power supply connections.
Double 4-pin bus connectors on the board simplify bus connections compared to older versions. The LED indicator will turn on when input voltage is applied to the board. Mounting holes are compatible with older versions, such as EI2C-9AI and EI2C-9AIA.
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Important: To prevent damage to the board, do not plug or unplug I2C cables while the power supply is on. Always turn off the power supply before connecting or disconnecting I2C cables.
