Allen-Bradley 1794-IT8

Technical specifications

Manufacturer

Allen-Bradley

Manufacturer part no.

1794-IT8

Type

Analog input module

Application

I/O module

Used with

FLEX I/O adapters and terminal bases

Input resolution

16 bits (2.384 µV typical)

Supported Thermocouple types

Type B: 300…1800 °C (572…3272 °F), Type C: 0…2315 °C (32…4199 °F), Type E: -270…+1000 °C (-454…+1832 °F), Type J: -210…+1200 °C (-346…+2192 °F), Type K: -270…+1372°C (-454…+2502 °F), Type N: -270…+1300°C (-454…+2372 °F), Type R: -50…+1768°C (-58…+3214 °F), Type S: -50…+1768°C (-58…+3214 °F), Type T: -270…+400°C (-454…+752 °F), Type TXK/SK(L): -200…+800°C (-328…+1472 °F)

Data format

16 bits, 2’s complement; Offset binary (unipolar)

Normal mode rejection ratio

-60 dB @ 60 Hz

Common mode rejection ratio

-115 dB @ 60 Hz -100 dB @ 50 Hz

Common mode input range

± 10V

Accuracy

With filter (max): 0.025% Full Scale @ 25 °C (±0.5 °C) (77 °F [±33 °F]), Without filter (max): 0.05% Full Scale @ 25 °C (±0.5 °C) (77 °F [±33 °F])

System throughput

325 ms (1 channel scanned), programmable to 28 ms 2.6 s (8 channels scanned), programmable to 224 ms

Open input detection

Available at system throughput rate

Open circuit detection type

Out of range reading (upscale)

Overvoltage capability

35V DC, 25V AC continuous @ 25 °C (77 °F) 250V peak transient

Channel bandwidth

0…2.62 Hz (-3 dB)

RFI immunity

Error of <1% of range @ 10V/m, 27…1000 MHz

Input offset drift with temperature

+6 µV/°C max

Gain drift with temperature, max

10 ppm/°C

Overall drift with temperature, max

50 ppm/°C of span

Cold junction compensation range

0…70 °C (32…158 °F)

Cold junction compensation

Allen-Bradley Cold Junction Compensation Kit, 1794-CJC

Dimensions (HxWxD), approx

46 x 94 x 53 mm (1.8 x 3.7 x 2.1 in.) 94 x 94 x 69 mm (3.7 x 3.7 x 2.7 in.) installed

Temperature, operating

-20…+55 °C (-4…+131 °F)

Technical documents (1)

• Rockwell Automation FLEX I/O selection guide 1794-SG002

Key features

• Eight point thermocouple input for Flex I/O
• 16 bit input resolution, 2.384 µV typical
• Open circuit detection reads out of range, upscale
• Common mode input range of ±10V
• Cold junction compensation with the 1794-CJC kit

About the Allen-Bradley 1794-IT8

The 1794-IT8 is a FLEX I/O 8 point thermocouple input module. Resolution is 16 bits (2.384 µV typical). Throughput is 325 ms with 1 channel scanned, programmable to 28 ms, or 2.6 s with 8 channels, programmable to 224 ms. Normal mode rejection is -60 dB at 60 Hz, and it works from -20…+55 °C (-4…+131 °F).

What is the 1794-IT8 used for?

It reads eight thermocouples into a FLEX I/O node: types B, C, E, J, K, N, R, S, T and TXK/SK(L). Data is 16 bits in 2's complement or offset binary (unipolar). Cold junction compensation uses the 1794-CJC kit.

Lifecycle and successor

Active Mature (Rockwell Automation lifecycle status, checked 24 October 2026).

Before you order

What to photograph or confirm so the right unit is quoted.

Read the catalog number 1794-IT8, the series letter and the firmware revision from the label. Send us a photo of the label and we confirm the match before we quote.