Allen Bradley 1746-NI4 SLC 500 High Resolution Analog Input Module 4 Point

Product Details

Related Product Model Recommendations

Payment & Delivery

FAQs

Q1: How do I select between voltage and current input on the 1746‑NI4?

Each of the 4 channels has a DIP switch on the circuit board. Setting the switch ON selects current mode (±20mA); setting it OFF selects voltage mode (±10V). Ensure the field device signal type matches the DIP switch setting—connecting a voltage source to a current‑configured channel may damage the module .

Q2: How are the input channels addressed in the PLC program?

If the module is installed in Slot 5, the input words are mapped as follows:

• Channel 0 → I:5.0

• Channel 1 → I:5.1

• Channel 2 → I:5.2

• Channel 3 → I:5.3

Each is a signed 16‑bit integer. The raw count range depends on signal type: ±20mA gives counts from –16,384 to +16,384; ±10V gives –32,768 to +32,767 .

Q3: What raw counts should I use for scaling a 4‑20mA transmitter?

For a 4‑20mA signal:

• 4 mA (minimum) → 3277 counts (under‑range value)

• 20 mA (maximum) → 16384 counts

Use these as InputMin and InputMax in the SCP (Scale with Parameters) instruction, and map them to your engineering units (e.g., 0–100 PSI). If the reading is stuck at 3277, the loop is likely open or polarity is reversed .

Q4: Is the 1746‑NI4 still in production?

No. The SLC 500 platform was formally discontinued by Rockwell Automation on March 31, 2024. The 1746‑NI4 is now only available through the used, refurbished, or third‑party market. For new projects, Rockwell recommends migrating to the CompactLogix 5380 platform with appropriate analog I/O modules .

Q5: What is the difference between the 1746‑NI4 and the 1746‑NIO4I?

The 1746‑NI4 is a pure analog input module with 4 input channels. The 1746‑NIO4I is a combination module featuring 2 analog inputs and 2 analog outputs in a single slot. The input section scaling and addressing on the NIO4I is identical to the NI4, making it a good choice for compact PID control loops.