Raw reading / ADC resolution
The built-in ADC converter converts the voltage on the input to a number
between 0 and 1023 (10 bit). This number is further scaled internally to 0-
10000.
To calibrate the raw ADC reading to the desired unit, use a 2-point
calibration and the helper feature in the web software.
See Calibrating analog inputs on page 44 for details
The tables below are average readings and can be used as a guide for
calibration. This table only apply to the physical inputs on the ezeio
™
.
0-5V
Input
Raw
0.0V
0
2.5V
4882
5.0V
9765
0-10V
Input
Raw
0.0V
0
5.0V
4927
10.0V
9855
0-30mA
Input
Raw
0.0mA
0
4.0mA
1395
20.0mA
6975
0-50kOhm *
Input
Raw
100Ω
107
1kΩ
902
10kΩ
4792
Note that when configured for resistance, the raw-to-Ohm relationship is not
linear.
Other devices may use other scaling on the inputs.
Consult the device manual for details.
Digital pulse input
Normally the value of an input represents a voltage, current or resistance. If
the sensor connected is of pulse type (such as a S0 pulse), the input can be
defined as a
Digital Pulse Input
by enabling this check box.
When this box is checked, the input value will reflect the time between the
two last transitions from low (<0.9V) to high (>1.1V) on the input. The time
is presented as milliseconds, and range from 4 to 99999999 (~28h). If no
pulses are detected, the max value will be returned.
The shortest pulse that can be detected in this mode is 2ms.
When in Digital pulse input mode, the count register will automatically
count up for each pulse.
The Digital Pulse input type is supported by the four inputs on the ezeio
™
and the eze System “Wireless I/O Expander”.
Consult the device manual for other device types.
Page 40 of 121
