1771-SPI
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Product Conditions
Product Conditions
Surplus: Surplus units show no signs of installation or having been used previously. These units are in the original packaging, which may have been opened.
Used: Used units have been previously used and are inspected, cleaned and tested.
All units come with a 1 Year Replace Industrial Warranty.
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Product Conditions
Replace Industrial, LLC is not affiliated with any of the manufacturers listed on this website. All products are sourced & verified through the industrial surplus market and through other independent supply chains. We do not convey any manufacturer warranty with the product. Each product sold comes with a 2 Year Replace Industrial Warranty, unless specified otherwise. This warranty conveys solely through Replace Industrial, LLC. and is completely unaffiliated with any manufacturer warranty. The terms of our warranty can be found here.
Surplus: This unit is sourced through the industrial market outside of the manufacturer and has been independently verified to not have been used operationally previously. These units are in the original packaging, but the packaging & unit may show signs of shelf wear.
Used: This unit may have been previously used and show signs of wear. The unit has been independently verified and is guaranteed with a 1 Year Replace Automation Warranty. The unit has been sourced through independent supply chains in the industrial markets.
Firmware: Replace Industrial, LLC sells hardware only and does not sell firmware and makes no representation as to what firmware may or may not be present on the hardware. We do not obtain or provide software for customers.
Allen-Bradley 1771-SPI
The Allen-Bradley 1771-SPI is a protocol interface module designed for PLC-5 systems, acting as a network master to control data exchange between the PLC-5 processor and up to 32 slave devices. Compatible with any slot in the 1771 I/O chassis, it draws 1.3A of current at 5V DC through the backplane. Communication is handled via an RS-485 multi-drop serial port paired with a Field Wiring Arm connector, operating in half-duplex asynchronous mode with speeds from 1200 to 19200 bps. The module supports IEEE floating-point formats and Block Data Transfer protocols, providing reliable data handling in industrial environments. It operates within a temperature range of 0 to 60°C and can tolerate up to 95% non-condensing humidity, with a non-operational temperature tolerance from -40 to 85°C.
| Manufacturer | Rockwell Automation |
| Brand | Allen-Bradley |
| Part Number | 1771-SPI |
| Product Type | Protocol Interface Module |
| Series | 1771 / PLC-5 |
| Function | Network Master for PLC-5 |
| Slave Device Support | Up to 32 Devices |
| Communication Interface | RS-485 Multi-drop Serial Port |
| Connector | Field Wiring Arm |
| Communication Mode | Half Duplex Asynchronous |
| Baud Rate Range | 1200 to 19200 bps |
| Protocols Supported | IEEE Floating Point, Block Data Transfer |
| Operating Temperature | 0 to 60°C |
| Storage Temperature | -40 to 85°C |
| Humidity | 5% to 95% Non-Condensing |
| Backplane Current | 1.3 A @ 5 V DC |
| Mounting | 1771 I/O Chassis Slot |
| Status | Discontinued / Legacy Support |
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