Description

The 1794-IRT8 is an Allen-Bradley FLEX I/O Thermocouple and Resistance Temperature Detector (RTD) module. This unit requires a nominal voltage of 24 Volts Direct Current. It also comes with 8 inputs.

• RTD Sensors supported: 100 ? Pt ? = 0.00385 Euro (-200…+870 °C) 100 ? Pt ? = 0.003916 U.S. (-200…+630 °C) 200 ? Pt ? = 0.00385 Euro (- 200…+630 °C) 500 ? Pt ? = 0.00385 U.S. (-200…+630 °C) 100 ? Nickel ? = 0.00618 (-60…+250 °C) 120 ? Nickel ? = 0.00672 (-60…+250 °C) 200 ? Nickel ? = 0.00618 (-60…+250 °C) 500 ? Nickel ? = 0.00618 (-60…+250 °C) 10 ? Copper ? = 0.00427 (- 200…+260 °C).
• Operating Shock: 30 g
• Vibration: 5g @ 10 to 500 Hz
• Storage Temperature: –40…85 °C (–40…185 °F)
• Operating Temperature: 0 to 55 C (32 to 131 F)
• Wire Size: Determined by installed terminal base
• Indicators: 1 green power status indicator 8 red open input indicators
• Mounting: DIN Rail
• ystem Throughput: 7.4 ms – mV 8.0 ms – ? – 2-wire 10.0 ms – ? – 3-wire 10.4 ms – ? – 4-wire 8.0 ms – 2-wire RTD ( °F) 10.4 ms – 4-wire RTD ( °F) 8.8 ms – 2-wire RTD ( °C), ( °K) 10.8 ms – 4- wire RTD ( °C), ( °K) 9.8 ms – 3-wire RTD ( °F) 10.0 ms – 3-wire RTD ( °C), ( °K) 8.0 ms – Thermocouples ( °F) 8.8 ms – Thermocouples ( °C), ( °K)?
• Data Format: °C (implied decimal point XXX.X) °F (implied decimal point XXX.X) °K (implied decimal point XXX.X) – 32767…+32767 0…65535 0…5000 (? mode) (implied decimal point XXX.X) -4000…+10000 (mV mode) (implied decimal point XXX.XX)
• Accuracy: 0.05% of full range in mV mode with filtering selected Hardware only = 0.10% of full range in mV mode
• Resolution: 14 bits
• Nominal input voltage ranges: -40…100 mV DC for thermocouples 0…325 mV for RTDs mV default
• Thermocouple Sensors supported: Type B: 300…1800 °C (572…3272 °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 TXK/XK (L):-200…800 °C (-328…1472 °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)
• Terminal base: 1794-TB3G, 1794-TB3GS, 1794-TB3GK
• Product Description: Flex IO 8-Channel RTD / Thermocouple Input Module
• Nominal voltage: 24 Volts DC
• Indicator: Power indicator
• Inputs: 8
• Accessories: 2 cold junction compensators
• Host system: FLEX I/O system

The 1794-IRT8 module is an Allen-Bradley FLEX Input/Output (I/O) millivolt, thermocouple, and resistance temperature detector (RTD) module. The 1794-IRT8 module features a nominal voltage rating of 24 Volts Direct Current and eight analog inputs. This thermocouple and RTD module is not conformally coated. The Allen-Bradley 1794-IRT8 FLEX I/O thermocouple and RTD module is meant to be part of a connected Allen-Bradley FLEX I/O system with the ability to perform broadly the same application functions as a rack-based I/O system. Within a pre-existing FLEX I/O system, the 1794-IRT8 thermocouple and RTD module must be connected to a power adapter as well as a terminal base. The thermocouple and RTD module contains both the bus interface and the application circuitry, while the terminal base features a terminal strip that can terminate either 2-wire or 3-wire devices. The adapter transfers read and write data to, as well as from, the 1794-IRT8 FLEX I/O thermocouple and RTD module. The Series B version of the Allen-Bradley 1794-IRT8 FLEX I/O module is also able to work with grounded thermocouples.

When the Allen-Bradley 1794-IRT8 module (Series B) is to operate in thermocouple (rather than RTD) mode, cold junction compensators are required. The 1794-IRT8 FLEX I/O thermocouple and RTD module ships with a pair of cold junction compensators for exactly this purpose. It can attach with up to eight RTD or thermocouple inputs. The front panel of the Allen-Bradley 1794-IRT8 FLEX I/O thermocouple and RTD module features a module identification nameplate, a user-customizable removable label, an indicator for key switch position, and an on/off indicator.