- Interfaces analog I/O signals to Ethernet
- Sixteen 16-bit differential analog inputs
- Up to eight 15-bit analog outputs with remote sense
- Measures voltage, thermocouple, and 4-20 mA
- Integral cold-junction compensation for thermocouples
- Fully electronic calibration
- Directly connects to field wiring
- Connects to Ethernet through 2601 I/O system hub
- DIN-3 rail mountable
Model 2608 is an analog I/O module that connects to Ethernet through a 2601 communication module. It has sixteen differential analog inputs and 0, 4, or 8 (model 2608-0, 2608-4, 2608-8) single-ended analog outputs. It is a member of the 2600 series of smart I/O modules.
Each analog input may be independently configured to measure voltage, thermocouple, or 4-20 mA current loop. The module has built-in 500 ohm resistors for current loop measurements, and cold-junction compensation sensors for thermocouple measurements. Dedicated input channels are used for cold-junction compensation sensors so that all sixteen external inputs will remain available for application use.
All analog inputs are fully differential so that common mode noise will be reduced or eliminated from measurements. Field wiring is connected directly to the 2608 through removable terminal blocks—no external breakout boards are needed.
The 2608 can be connected to any of the sixteen IOM (I/O module) ports on the 2601 with a low-cost category-5 patch cable, which provides all operating power and communication signals needed by the 2608. All inter-module communication circuits are optically isolated to prevent potentially disruptive ground loops.
Interfacing a large number of analog signals to one Ethernet port
||±10 V, ±100 mV
||500 samples/second for each channel
||6.1 µV (10 V range), 60.1 µV (100 mV range)
|Output voltage range
||2 mA, max
|Power and Environmental|
||24 VDC, 80mA
||0 to 70 °C
||(W x H x D): 8.62 x 4.87 x 2.62 inches; 219 x 124 x 67 mm