Allen-Bradley 1769-IF8 Compact I/O 8-Channel Analog Input Module

Eight analog inputs for voltage and current signals

The Allen-Bradley 1769-IF8 is an eight-channel analog input module for 1769 Compact I/O. Each channel can be configured as a voltage input (plus or minus 10 V, 0 to 10 V, 0 to 5 V, 1 to 5 V) or as a current input (0 to 20 mA or 4 to 20 mA), in differential or single-ended connection, so the module can serve transmitters, potentiometers and instrument signals in one slot.

The converter is delta-sigma with 16-bit resolution in unipolar ranges and 15 bits plus sign in bipolar ranges. When the input goes beyond the normal range the module sets an over- or under-range flag but keeps converting up to the full-scale range, which allows a transmitter fault current to be seen.

Technical specifications

Accuracy, filtering and update time

Accuracy at 25 °C is plus or minus 0.2% of full scale on voltage and 0.35% on current, with module error of 0.3% and 0.5% over temperature, and non-linearity and repeatability of 0.03%. Voltage inputs present 220 kΩ and current inputs 250 Ω.

A filter frequency selection sets the response: 10 Hz gives 100 ms per channel and 400 ms per module, 50 or 60 Hz gives 30 ms and 120 ms, and 500 Hz gives 6 ms and 24 ms. Common-mode rejection is greater than 60 dB at 50 and 60 Hz with the 10 Hz filter, and the common-mode voltage must stay within plus or minus 10V DC of the analog common.

Wiring and bank notes

Rated working voltage is 30V AC or 30V DC, with overload protection to 30V DC on voltage inputs and 32 mA on current inputs. Isolation between the inputs and the bus is qualified at 500V AC or 710V DC for one minute. The module is 1.5 slots wide, weighs 450 g and draws 120 mA at 5.1V DC and 70 mA at 24V DC; heat dissipation is 3.24 W.

Use shielded cable such as Belden 8761 or equivalent and ground the shield per the wiring guidelines. The power-supply distance rating is 8 modules. Wire with 22 to 14 AWG solid or 22 to 16 AWG stranded copper, 90 °C, on the 18-pin terminal block.

Related Allen-Bradley products: Allen-Bradley 1769-IF4 Compact I/O 4-Channel Analog Input, Allen-Bradley 5069-IF8 Compact 5000 8-Channel Analog Input, Allen-Bradley 1769-OF4 Compact I/O 4-Channel Analog Output, Allen-Bradley 1794-IE8 FLEX I/O 8-Channel Analog Input, Allen-Bradley 5094-IF8 FLEX 5000 8-Channel Analog Input Module and Allen-Bradley 1762-IF4 MicroLogix 1200 4-Channel Analog Input Module.

Documents and quotation

The Compact I/O technical data 1769-TD006 holds the IF8 table and response data. For a quotation send the 1769-IF8 reference, series, quantity, the controller or adapter and the signal types per channel. Related hardware is listed in PLC & I/O Cards.

How the 1769-IF8 Works

The 1769-IF8 converts each enabled channel with a delta-sigma converter. Voltage signals are measured across a high-impedance input, and current signals are converted to voltage across the internal 250 ohm resistor. In differential wiring each channel is measured between its own plus and minus terminals, which rejects noise picked up equally on both wires; in single-ended wiring the minus terminals are tied to a shared reference.

The filter frequency sets the integration time and therefore the balance between noise rejection and update speed, as shown in the update-time figures above. Because the module updates its channels in sequence, disabling unused channels can shorten the module update time. Over-range and under-range flags let the controller detect a transmitter fault or a broken loop.

1769-IF8 Selection & Ordering Guide

• Channel count: the 1769-IF4 offers four channels and the 1769-IF16C sixteen current-only channels; the 1769-IF8 suits mixed voltage and current signals in larger numbers.
• Coated version: the 1769-IF8K is the conformal-coated variant.
• Bank layout: the module is 1.5 slots wide and must sit within eight modules of the 1769 power supply.
• Power budget: include the 120 mA at 5.1V DC and 70 mA at 24V DC in the bank calculation.
• Platform: used with a CompactLogix controller, as MicroLogix 1500 expansion I/O or with a 1769 communication adapter.

When you request a quote, list the series letter and signal type of each channel. Our team can help confirm the correct ordering code.

Installation & Maintenance

Remove power before installing or removing the module. Use shielded twisted-pair cable, ground the shield at one end, keep analog wiring separate from power and drive cables, and tighten terminals correctly. In service, review the channel status bits, check readings with a loop calibrator or voltage source, and keep the cabinet clean and ventilated.

Typical Applications in Oman & the GCC

• CompactLogix-based skids in oil and gas, chemical injection and gas compression.
• Water treatment, pumping stations and desalination plants.
• HVAC, chillers and district cooling plant monitoring.
• Process lines in food, beverage and building materials plants.

Keep panels in hot plant rooms within the rated operating temperature of the 1769-IF8.

Why Source the 1769-IF8 from Seven Star LLC

Seven Star LLC supplies Allen-Bradley Compact I/O modules, including the 1769-IF8, across Oman and the GCC. Request a quote with the catalog number and quantity.