Flowmetrics 922-MFC Installation And Operating Instructions Manual page 61

Typical RTD Input Schematic
5.13 Digital Flow Input:
Number:
Range:
Sensor Types:
Max Input Frequency: 40kHz max
Min pulse width:
Thresholds:
Input Impedance:
Excitation Voltage:
Min. Frequency to maintain rate display: 5 Hz
Typical Digital Pulse Input Schematic
5 VDC
@ 0.9 mA
2 mA Excitation Current Output
20 KΩ
1.5 uF
20 KΩ
1.5 uF
100 KΩ
1 (Flow only)
3-30 VDC Pulse
Dry contact, opto-isolated or voltage
source
10µsec (with 40kHz filter)
OFF is less than 2.0V
ON is greater than 2.5V
40KΩ to ground minimum
5VDC through 5.6KΩ resistor
5.6 K Ω
+5 VDC
+5 VDC
39 K Ω
100 K Ω
5-3
˜˜ A/D
Counter