Allen-Bradley 1769-IF16C Compact I/O 16-Channel Current Input

Sixteen 4-20 mA inputs in one Compact I/O slot

The Allen-Bradley 1769-IF16C packs sixteen single-ended current inputs into one 35 mm slot of a Compact I/O rack. It is aimed at plants with many 4-20 mA transmitters, such as tank levels, pump pressures and temperature transmitters, where the cost and space of individual four-channel modules would be high.

The 16-bit sigma-delta converter reads 0-20 mA or 4-20 mA with an accuracy of ±0.5 percent of full scale at 25 °C and a module error of 1.25 percent. Input impedance is 249 ohms. A sensor or transmitter power supply, which must be Class 2, is wired externally, with the signal wired to the input terminal and the return to a common terminal.

Technical specifications

Speed, filtering and wiring

Update time depends strongly on the filter selection. With the 16 Hz filter the module updates in 1600 ms for all sixteen inputs, with 200 ms per input; with the 315 Hz filter it takes 120 ms; and with the 1365 Hz filter 40 ms. Choose the slower filters for noise immunity on slow process variables and the faster ones only where the application needs quick response.

Both terminals of each channel must remain within ±10 V DC of analog common, and the continuous overload limit is ±28 mA. The module draws 190 mA at 5.1 V DC and 70 mA at 24 V DC from the bus, so check the budget of the power supply and the controller when building a rack with several analog modules.

1769-IF16C and 1769-IF16V

The 1769-IF16V in the same document is the 16-channel voltage version, with 0-10 V, 1-5 V and ±10 V ranges. Do not substitute one for the other: the current module has a 249 ohm shunt and cannot read voltage signals. For four mixed channels use the 1769-IF4.

Documents and quotation

The Rockwell Automation 1769 Compact I/O specifications document is attached. See our PLC and I/O cards category for related controllers and modules such as the 5069-L320ER CompactLogix 5380 controller. Confirm the exact catalog number, series letter and firmware or hardware revision on the product label, and the compatibility with your existing system, before ordering. Stock and lead time are confirmed at quotation.

How the 1769-IF16C Works

Each of the sixteen channels of the 1769-IF16C passes the loop current through a 249 ohm precision resistor and measures the voltage across it with a sigma-delta converter. Because the inputs are single-ended, all channels share an analog common, which is how sixteen channels fit in one slot. The module does not power the loops: two-wire transmitters are powered from an external Class 2 supply, with the signal returning through the module input to the common.

The selected filter sets the trade-off between noise rejection and update time, and the module updates the channels in sequence, so the total module update time is roughly the per-input time multiplied by the number of enabled channels. Disabling unused channels shortens the update time. Values are reported to the controller in the selected data format, with status bits for over-range and under-range conditions.

1769-IF16C Selection & Ordering Guide

• Current only: the 1769-IF16C reads current signals; use the 1769-IF16V for voltage and the 1769-IF4 or 1769-IF8 for mixed ranges.
• Power budget: add the 190 mA at 5.1V DC and 70 mA at 24V DC to the bus budget of the power supply.
• Distance rating: place the module within eight modules of the 1769 power supply.
• Accessories: a replacement terminal block is the 1769-RTBN18; each bank also needs an end cap terminator.

When you request a quote for the 1769-IF16C, send the series letter and the controller or adapter in use. Our team can help confirm the correct ordering code.

Installation & Maintenance

Remove power before installing the module. Use shielded twisted-pair cable for each loop, ground the shields at one point, and keep analog cables apart from power and drive cabling. Size the external transmitter supply for all loops. During maintenance, monitor the channel status bits, check terminal screw torque, and verify suspect channels with a loop calibrator before replacing hardware.

Typical Applications in Oman & the GCC

• Tank farms and terminals reading many level and pressure transmitters.
• Water and wastewater plants and pumping stations.
• Desalination and reverse-osmosis skids with multiple flow and pressure loops.
• HVAC and district cooling plants monitoring temperatures and pressures.

In hot climates keep the panel within the 0 to 60 °C operating range.

Why Source the 1769-IF16C from Seven Star LLC

Seven Star LLC supplies Allen-Bradley Compact I/O modules, including the 1769-IF16C, across Oman and the GCC. Request a quote with the catalog number and quantity.