Overview
Manuals
More Features
Lifecycle and Migration Status
Features:
- 8 isolated current-only input channels
- 4 to 20 mA (with operational threshold limits spanning 0.1 to 21 mA)
- High-precision 16-bit unipolar resolution yielding 330 nA/bit (0.34 µA/bit)
The Allen-Bradley 1771-NIS is an I/O module belonging to the 1771-N high-resolution I/O module family. It features eight current input channels with a rated current range of 4-20mA. The 1771-NIS module provides loop power to the input circuitry. The 1771-NIS draws 2.4A from the I/O chassis backplane, with a total power consumption of 12W. The 1771-NIS can be connected to PLC-5/250, PLC-3, and PLC-5 controllers.
Allen-Bradley recommends using the 1771-NIS with the RTP-4 (RTP-4 is suitable for applications other than thermocouples). Power to the I/O chassis should be turned off before installing or removing any I/O module. The optimal operating temperature range for the 1771-NIS is 0 to 60°C, and the relative humidity range is 5% to 95% (non-condensing).
The 1771-NIS/B Allen Bradley High-Resolution Analog Input Module Series B may still be available for purchase and support from Moore Automated Company beyond End-Of-Life (EOL) by the manufacturer (OEM).
Allen Bradley 1771-NIS/B High-Resolution Analog Input Module Series B Manuals(Datasheets), Link
Important Notice: Other accessories, manuals, cables, calibration data, software, etc. are not included with this equipment unless listed in the above stock item description. All prices are shown in USD.
The 1771-NIS/B input channels support a current range of 0.1 – 21mA. The input channel resolution is 330nA/bit (16-bit unipolar), and the maximum input impedance is 300Ω. The module provides a 20 – 30V DC loop power supply (current range 0 to 20mA). The 1771-NIS/B module detects open circuits within 5 seconds and provides 24V DC overvoltage protection. Its common-mode rejection ratio (CMRR) is 150 dB, with a typical value of 50 dB. Offset drift is ±200 nA/°C, and gain drift is ±95 ppm/°C. Update time per module is up to 25 seconds, and the input channel bandwidth is 9 Hz. Lower and upper limits are 3.2 mA and 21 mA, respectively. The calibration values for the 1771-NIS/B input channels are 1 mA / 21 mA.
According to Rockwell Automation records, the entire 1771 platform was officially discontinued on May 31, 2017. When upgrading outdated PLC-5 infrastructure, engineering departments typically migrate this hardware architecture to the modern ControlLogix platform. A simple conversion method is to map this module to a ControlLogix 1756 analog input module and utilize the dedicated 1492-CONACAB migration cabling system to preserve existing patch panel field cabling.
