NI PCI-485I2

Description

Detailed parameter table

NI PCI-485I2

Product introduction

The NI PCI-485I2 is an industrial-grade serial communication card developed by National Instruments (NI), a leader in industrial automation and test technology. As a key product in NI’s serial communication lineup—renowned for ruggedness and reliability—the NI PCI-485I2 is engineered to enable stable, high-speed data transmission in harsh industrial environments, such as factory automation and process control.

Designed for engineers and system integrators, the NI PCI-485I2 features 2 independent RS-485/RS-422 ports, each supporting data rates up to 10 Mbps—ideal for connecting to industrial devices like PLCs, sensors, and motor drives. Unlike consumer-grade serial cards, its 2.5 kVrms isolated drivers protect against voltage spikes and ground loops, common in industrial settings.

At its core, the NI PCI-485I2 merges industrial durability with flexible software integration. Powered by NI’s NI-Serial driver, it supports popular industrial protocols like Modbus RTU and works seamlessly with NI’s programming tools (e.g., LabVIEW) for custom application development. Whether deployed in a manufacturing plant’s control system or a test bench for serial device validation, the NI PCI-485I2 ensures uninterrupted data flow, while its PCI interface guarantees easy integration into existing industrial PCs.

Core advantages and technical highlights

Isolated drivers for industrial noise immunity

The NI PCI-485I2’s 2.5 kVrms isolated drivers are a critical advantage for industrial use. They isolate each serial port from the PC chassis and from other ports, preventing ground loops and voltage transients that can corrupt data or damage equipment. For example, in a factory with multiple PLCs connected to a single PC, ground potential differences between machines could cause signal interference— but the NI PCI-485I2’s isolation eliminates this risk, ensuring reliable communication even in noisy electrical environments. This ruggedness makes it a top choice for process control applications where downtime is costly.

High-speed, multi-port communication

With 2 independent ports and data rates up to 10 Mbps per port, the NI PCI-485I2 enables parallel, high-throughput serial communication. In a packaging plant, for instance, one port can send control commands to a conveyor belt motor drive (via Modbus RTU) at 1 Mbps, while the other port collects real-time status data from a vision sensor at 5 Mbps—no port contention or speed bottlenecks. The 4 kB FIFO buffers per port further prevent data loss during high-traffic periods, ensuring smooth transmission even when multiple devices send data simultaneously.

Flexible protocol support and software integration

The NI PCI-485I2 supports both RS-485 (half-duplex, multi-drop) and RS-422 (full-duplex, point-to-point) modes, adapting to diverse industrial device requirements. It natively works with Modbus RTU/ASCII— the most common protocol for industrial sensors and controllers— and can be configured for custom serial protocols via NI’s software tools. For example, in a water treatment plant, engineers can use LabVIEW to program the NI PCI-485I2 to communicate with a custom flow meter using a proprietary serial protocol, while also connecting to a standard Modbus-enabled pH sensor on the second port. This flexibility reduces the need for multiple communication cards.

Industrial-grade durability and protection

Built to withstand harsh industrial conditions, the NI PCI-485I2 includes EMI/RFI shielding to block electromagnetic and radio-frequency interference—critical in environments with motors, inverters, or high-voltage equipment. It also features hot-swap protection, allowing users to connect or disconnect serial devices without powering down the PC (when used with hot-swap-compatible terminals). The automatic software-selectable bus termination simplifies setup: users can enable 120 Ω termination for long RS-485 cables (up to 1200 m) directly via software, eliminating the need for external resistors and reducing installation time.

Typical application scenarios

Factory automation and PLC communication

In factory automation, the NI PCI-485I2 serves as a bridge between industrial PCs (IPCs) and PLCs. For example, in an automotive assembly line, an IPC with the NI PCI-485I2 connects to 10 Allen-Bradley Micro800 PLCs via RS-485. One port sends production schedule data to the PLCs (Modbus RTU, 500 kbps), while the other port collects real-time data (e.g., robot position, conveyor speed) for monitoring on a LabVIEW dashboard. The NI PCI-485I2’s isolation prevents voltage spikes from welding robots from disrupting communication, ensuring the assembly line runs without unplanned stops.

Process control and sensor data acquisition

In process industries like oil and gas or chemical manufacturing, the NI PCI-485I2 collects data from distributed sensors. For a chemical plant’s reactor monitoring system, the card connects to 8 RS-485-enabled pressure sensors (multi-drop configuration) on one port, sampling data at 100 kbps to track reactor pressure. The second port communicates with a Modbus RTU-enabled temperature controller, sending setpoint adjustments and receiving current temperature readings. The NI PCI-485I2’s high noise immunity ensures accurate data capture even near large pumps or heaters, while its long cable support (up to 1200 m) lets sensors be placed close to the reactor without signal degradation.

Test and validation of serial devices

In electronics manufacturing, the NI PCI-485I2 is used to test RS-485/RS-422 devices like industrial routers or IoT gateways. For a router manufacturer’s production line, the card connects to 2 routers simultaneously: one port sends test commands (e.g., data rate changes, protocol switches) at 10 Mbps, while the other port monitors the router’s response to verify compliance with industry standards. The NI PCI-485I2’s software flexibility allows engineers to automate tests via LabVIEW, generating test reports and flagging defective units—reducing manual testing time by 40% compared to standalone serial testers.

NI PCI-485I2

Related model recommendations

NI PCI-485

A single-port version of the NI PCI-485I2, with 1 RS-485/RS-422 port (vs. 2). It’s a cost-effective choice for applications needing only one serial connection (e.g., basic PLC communication) while retaining the same isolation (2.5 kVrms) and data rate (up to 10 Mbps) as the NI PCI-485I2.

NI USB-485

A USB-powered serial communication module that complements the NI PCI-485I2. Unlike the PCI-based NI PCI-485I2, it’s portable and works with laptops—ideal for field service or temporary test setups (e.g., troubleshooting a remote sensor). It shares the same NI-Serial driver compatibility, making it easy to switch between lab (NI PCI-485I2) and field (USB-485) use.

NI PCIe-485

A PCI Express upgrade to the NI PCI-485I2, offering faster bus speeds (PCIe x1) and improved compatibility with modern PCs (which often lack PCI slots). It has 2 ports, 2.5 kVrms isolation, and 10 Mbps data rates—matching the NI PCI-485I2’s performance while future-proofing systems with PCIe architecture.

NI 9842

A CompactRIO (cRIO) serial module that pairs with the NI PCI-485I2 for distributed systems. The NI PCI-485I2 handles communication in a central IPC, while the 9842 (installed in a cRIO chassis) communicates with sensors in remote locations. They use the same NI-Serial driver, ensuring consistent data formatting across the system.

NI LabVIEW 2024

Essential software for maximizing the NI PCI-485I2’s capabilities. LabVIEW provides pre-built VIs for Modbus communication, serial data logging, and dashboard creation—letting users build custom monitoring systems without low-level programming. For example, engineers can use LabVIEW to visualize sensor data from the NI PCI-485I2 in real time, set up alerts for abnormal values, and log data to a database.

NI PCI-8516

A CAN/LIN communication card that works alongside the NI PCI-485I2 in automotive test systems. The NI PCI-485I2 handles RS-485 communication with industrial sensors, while the PCI-8516 communicates with CAN-based vehicle ECUs—creating a comprehensive test setup for automotive manufacturing.

Installation, commissioning and maintenance instructions

Installation preparation

Before installing the NI PCI-485I2, power off the PC and ensure it has an empty PCI slot (PCI 2.2/2.3 compliant). Wear an ESD wristband to prevent electrostatic damage. Insert the card firmly into the PCI slot and secure it with the chassis screw. Connect serial devices to the card’s terminal block: match RS-485/RS-422 signals (A, B, GND) to the device’s pins, and enable bus termination (120 Ω) via software if using cables longer than 100 m. Download and install the latest NI-Serial driver from NI’s website—this enables communication between the card and your PC. For multi-port setups, use NI’s Measurement & Automation Explorer (MAX) to assign unique COM ports to each port and test communication with a loopback test.

Maintenance suggestions

To maintain the NI PCI-485I2’s performance, inspect the terminal block quarterly for loose wires or corrosion—tighten screws if needed and clean contacts with a dry, lint-free cloth. Avoid exposing the PC (and card) to extreme temperatures or moisture (adhere to the 0 °C–55 °C operating range) to prevent component degradation. If communication errors occur, check for damaged cables (replace if frayed) and verify the data rate, parity, and flow control settings match the connected device. Update the NI-Serial driver annually to access bug fixes and compatibility improvements for new operating systems. For isolation testing, use a multimeter to verify port-to-chassis isolation (should remain ≥2.5 kVrms); if not, contact NI support for service. Use only NI-certified spare parts (e.g., terminal blocks) for repairs to ensure compliance with industrial safety standards.

Service and guarantee commitment

National Instruments (NI) backs the NI PCI-485I2 with a 1-year standard warranty, covering defects in materials and workmanship. For extended protection, customers can purchase NI’s ServicePlus plan, which extends coverage up to 3 years and includes priority technical support and calibration services. NI’s global technical team—specialized in industrial serial communication—is available 24/7 via phone, email, and online chat to assist with setup, troubleshooting (e.g., resolving Modbus communication issues), or software integration.

NI also provides free resources: application notes on RS-485 network design, LabVIEW example code for the NI PCI-485I2, and a user community where engineers share tips for industrial communication. If the card fails within the warranty period, NI will repair or replace it at no cost, with expedited shipping to minimize downtime. This commitment reflects NI’s confidence in the NI PCI-485I2’s durability and its dedication to supporting customers in their critical industrial automation and test tasks.