Allen-Bradley 1771-NB4T High-Resolution Thermocouple/mV Input Module

The 1771-NB4T is a high-resolution thermocouple and millivolt input module designed for the Allen-Bradley PLC-5 control platform. It supports two temperature or millivolt input channels and includes two 0-25 mA outputs. Supported thermocouple types include B, E, J, K, R, S and T, providing multiple sensor options for temperature measurement applications.

Technical Specifications

Input Measurement and Sensor Compatibility

The 1771-NB4T accepts thermocouple and millivolt signals through two input channels. Thermocouples generate low-level voltage signals corresponding to temperature differences, while millivolt input capability allows the module to process compatible low-level voltage signals.

The supported thermocouple types are B, E, J, K, R, S and T. These sensor types have different temperature characteristics and calibration curves, so the configured sensor type must match the thermocouple connected to each input channel.

Analog Output Configuration

In addition to its two measurement inputs, the 1771-NB4T provides two 0-25 mA output channels. This combination of input measurement and analog output capability allows the module to handle both signal acquisition and current-signal output within the PLC-5 system.

The 0-25 mA range should be distinguished from the more common 4-20 mA instrumentation range. The actual output scaling, connected load requirements and control configuration should be verified against the applicable technical documentation before integration.

PLC-5 System Application

The 1771-NB4T is intended for PLC-5 system configurations requiring thermocouple or millivolt signal acquisition. Its combination of two sensor inputs and two analog outputs provides measurement and signal-output functions in a single module.

When replacing an existing module, verify the PLC-5 rack configuration, thermocouple type, input signal requirements and analog output wiring. The shared PLC-5 platform designation alone does not establish interchangeability with other 1771-series analog modules.

Product Availability and Warranty

The 1771-NB4T is discontinued by the manufacturer. According to the supplied product listing, the original factory warranty does not apply, and a Radwell 2-year warranty is included.

For procurement and maintenance purposes, confirm the complete model number and required input/output configuration before ordering.

Frequently Asked Questions

Q: Which thermocouple types are supported by the 1771-NB4T?

A: The listed supported sensor types are B, E, J, K, R, S and T. The configured sensor type must correspond to the thermocouple connected to the input channel.

Q: How many inputs and outputs does this module provide?

A: The 1771-NB4T provides two thermocouple/millivolt inputs and two 0-25 mA outputs.

Q: Can the 1771-NB4T be used as a standard 4-20 mA analog output module?

A: Its listed output range is 0-25 mA, not exclusively 4-20 mA. Compatibility with a particular 4-20 mA application depends on output configuration, scaling and the connected device requirements.