User's Manual

268XA
Service Manual
1-28
Table 1-34. FAI A/D Thermocouple Specifications (cont.)
Thermistor
Accuracy + °C
90 Day 1 Year
Temp °C Range*
Slow Slow
-40 to 150 100 to 100 mΩ 0.4 0.51 18 to 23 °C
Steinhart – Hart Equation: 1/(T
o
Kelvin) = A + B*(ln Ω) + C*(ln Ω)
3
Default constants are supplied only for a YSI (type 004) 2,252 Ω thermistor, you can enter
constants for other thermistors. The ranges of thermistor constants are as follows: A 1.0E-4 to
1.0E-2, B 1.0E-5 to 1.0E-3, and C 1.0E-8 to 1.0E-6.
* Assumes 4-wire measurement.
FAI A/D Frequency Measurement Specifications
The following tables provide FAI A/D specifications for the frequency measurement
function.
Table 1-35. FAI A/D Frequency Accuracy Specifications
Frequency Measurement Accuracy, 1 Year, -10 °C to 60 °C
Range Resolution Accuracy + (% input + Hz)
Slow Fast Slow Fast
15 Hz to 900 Hz 0.01 Hz 0.1 Hz 0.05%+0.02 Hz 0.05%+0.2 Hz
900 Hz to 9 kHz 0.1 Hz 1 Hz 0.05%+0.1 Hz 0.05%+1 Hz
9 kHz to 90 kHz 1 Hz 10 Hz 0.05%+1 Hz 0.05%+10 Hz
90 kHz to 900 kHz 10 Hz 100 Hz 0.05%+10 Hz 0.05%+100 Hz
1 MHz 100 Hz 1 kHz 0.05%+100 Hz 0.05%+1 kHz
Table 1-36. FAI A/D Frequency Sensitivity Specifications
Frequency Range Minimum Signal Maximum Signal
15 Hz to 70 kHz 100 mV ac rms 30 V ac rms
70 kHz to 100 kHz 100 mV ac rms 20 V ac rms
100 kHz to 200 kHz 150 mV ac rms 10 V ac rms
200 kHz to 300 kHz 150 mV ac rms 7 V ac rms
300 kHz to 1 MHz Linearly increasing from 150 mV
ac rms at 300 kHz to 2 V ac rms
at 1 MHz
Linearly decreasing from 7 V ac
rms at 300 kHz to 2 V ac rms
at 1 MHz