Measurement Computing CIO-DAS-TC - Manual (Page 2)

1
Specifications
Typical for 25 °C unless otherwise specified.
Specifications in italic text are guaranteed by design.
Analog input
Table 1. Analog input specifications
A/D converter type AD652 V/F converter
Number of channels 16 differential thermocouple inputs, 1 CJC input
Programmable ranges 2.5 V to +10 V, 20 mV to +80 mv, 15 mV to +60 mV, 6.25 mV to 25 mV
Voltage gains 1, 125, 166.7, 400
Thermocouple types J, K, E, T, R, S, B
A/D pacing Continuous conversions. Software-programmable for 50 Hz, 60 Hz, or 400 Hz
A/D trigger sources Software-triggered
Data transfer Single I/O register transfer through dual port RAM
Conversion rates (integrating
time) 50 Hz, 60 Hz, 400 Hz
Software programmable
*Conversion rates
(per channel) 25.0 msec @ 50 Hz typical, 25.5 msec maximum
21.6 msec @ 60 Hz typical, 22.1 msec maximum
7.4 msec @ 400 Hz typical,7.9 msec maximum
*This is the total time to convert the channel, process the data, and provide a
delay to switch the gain and channel.
Linearity error (A/D specs) ±0.05% @ 4 MHz clock
Gain drift (A/D specs) ±75 ppm/°C max
Zero drift (A/D specs) ±50 uV/°C max
Power supply rejection ratio 0.01 %/V
Overvoltage protection 40 V to +55 V
CMRR @ 60 Hz 80 dB minimum
Input leakage current ±80 nA maximum
Input impedance 100 MegOhm minimum
Absolute maximum input
voltage 40 V to +55 V
Isolation to PC 500 V min through DC/DC converter and opto-isolators
Accuracy and resolution
Table 2. Accuracy and resolution (voltage measurements)
Gain Range Accuracy (Worst Case) Resolution
@ 50 Hz @ 60 Hz @ 400 Hz
1 2.5 to 10 V ±0.01% of reading ±2.5 mV 312.5 µV 375 µV 2.5 mV
125 20 to 80 mV ±0.01% of reading ±20 µV 2.5 µV 3.0 µV 20.0 µV
166.7 15 to 60 mV ±0.01% of reading ±15 µV 1.88 µV 2.25 µV 15.0 µV
400 6.25 to 25 mV ±0.02% of reading ±6.25 µV 0.781 µV 0.938 µV 6.25 µV