All AI modules connect to analog (value) sensors. The FRN1980 option provides eight ±2.5 Vdc inputs. Each of the 8 inputs, plus ground and temperature, are opto-switched into a precision A-to-D converter; ground is measured so short-term drift may be cancelled and temperature is measured so that the temperature drift associated with all silicon-based chips may be negated. The result is 13 bit resolution of the analog input; simply put, there are 8000 steps over the total range with an accuracy of ±0.05%. This module utilizes the total range as their active range. Availability: Usually ships in 6-8 weeks. FRN1980 >>>> JAN 31, 2008 <<<< LAST DAY TO ORDER NEW MOSCAD/MOSCAD-L UNITS, PARTS & ACCESORIES When purchasing MOSCAD hardware/software or any product with NO dollar amount, a quote containing ALL PRICING will be e-mailed before the order is processed.