NFAI835-S51 Analog Input Output Module YOKOGAWA 4-20mA

YOKOGAWA NFAI835-S51 Analog I/O Module

• Brand & Model: YOKOGAWA / NFAI835-S51 – 4-channel input, 4-channel output, isolated.
• Input Channels: 4 channels accept 4 to 20 mA signals from transmitters. You can configure each channel for 2-wire or 4-wire transmitters via terminal connections.
• Output Channels: 4 channels source 4 to 20 mA to actuators or control devices. Each output features a fallback value that you set per channel for safety.
• Transmitter Power Supply: The module provides a loop power supply of 20.2 to 29.3 V DC, with a current limit of 25 mA per channel.
• Isolation & Withstanding Voltage: The NFAI835-S51 withstands 500 V AC between input/output and system, and 500 V AC between individual channels. This ensures robust noise rejection and long-term reliability.
• Accuracy & Drift: Input accuracy is ± 0.1 % of full scale. Output accuracy is ± 0.3 % of full scale. Temperature drift stays within ± 0.01 % per °C, maintaining stable performance across a wide operating range.
• Speed & Response: The data refresh cycle is 10 ms. Both input and output step response times are 100 ms, enabling fast closed-loop control.
• Environmental & Physical: The module operates from -20 °C to +70 °C. It consumes 360 mA at 5 V DC and 450 mA at 24 V DC. The unit weighs only 0.3 kg and uses a 40-pin MIL connector.
• HART & Protocols: Built-in HART passthrough allows you to communicate with smart field devices. RTU, WTR, and PCT options are enabled for this specific version.

Technical Specifications Overview

• Model: YOKOGAWA NFAI835-S51 (Analog I/O, 4 in / 4 out).
• Input Range: 4 to 20 mA (scalable).
• Output Range: 4 to 20 mA (sink/source).
• Resolution: 14-bit for input, 12-bit for output (typical).
• Linearity: ± 0.05 % of span (input), ± 0.1 % of span (output).
• Frequency Response: DC to 30 Hz (-3 dB) for both input and output.
• Sensitivity: 1 µA per count for input, 2 µA per count for output.
• Temperature Range: Operating -20 °C to +70 °C; storage -40 °C to +85 °C.
• Humidity Tolerance: 5 % to 95 % RH (non-condensing).
• Interference Immunity: Common mode rejection > 120 dB at 50/60 Hz. Series mode rejection > 60 dB at 50/60 Hz.
• Dielectric Strength: 500 V AC for 1 minute between channels and system.

Frequently Asked Questions (FAQ)

• Q: Can I use the NFAI835-S51 with a YOKOGAWA Centum VP system?
  A: Yes, the NFAI835-S51 is fully compatible with all YOKOGAWA DCS series that use the standard backplane.
• Q: Does this module support HART communication on both inputs and outputs?
  A: Yes, HART passthrough works on all 4 input channels and all 4 output channels.
• Q: What is the maximum cable length for the 4-20 mA signals?
  A: For analog signals, we recommend a maximum cable length of 300 meters for reliable accuracy.
• Q: Can I configure the output fallback value while the system runs?
  A: Yes, you can set the fallback value per channel online without stopping the controller.
• Q: Do you have stock for this model right now?
  A: Yes, we keep the NFAI835-S51 in stock for immediate shipment.
• Q: What is the return policy if the module does not fit my application?
  A: We offer a 30-day return policy – just contact us for an RMA number.
• Q: Does the module provide transmitter power for 4-wire devices?
  A: The internal power supply (20.2–29.3 V) can power 2-wire transmitters. For 4-wire, you need an external supply.
• Q: How does the module handle overvoltage on input channels?
  A: Each input includes overvoltage protection up to ±30 V DC without damage.

Contact Information Inquiries: sales@nex-auto.com , +86 153 9242 9628

Partner NexAuto Technology Limited: https://www.nex-auto.com/