LSIS XBF-AD08A

XGB Analog edition manual
8.6 Functions of Analog Input Option Board
The functions of analog input option board are as follows.
Function
Description
Channel
operation/stop setting
● Specify operation/stop of the channel which will perform A/D conversion.
● Specifying unused channels as Stop can shorten overall operation time.
Input
Voltage /current
range setting
● Specify desired range of analog I/O.
● Analog input option board provides 2 ranges(4~20mA, 0~20mA) of current I/O and 1
range ( 0~10V) of voltage I/O.
Output data type
setting
● Specify digital I/O types.
● This module provides 4 output data types (Unsigned, Signed, Precise, and Percentile
Values)
A/D input conversion
method
● Sampling Process
- If A/D conversion method has not been specified, the module processes sampling.
● Averaging process
- Outputs A/D converted value averaged by
count to reduce rapid change of input
value caused by external noise
8.6.1 Sampling Process
In popular A/D conversion process, analog input signals are collected at constant time intervals and
A/D converted. The time elapsed for the analog signals to be converted into digital signals and
saved in memory device depends upon the number of channels used.
(Process Time) = (No. of Channels Used) x (Conversion Speed + Scan time)
(Ex.) Process time when using 1 of 2 I/O channels and scan time is 2㎳;
1 x (1 ㎳ + 2㎳) = 3 ㎳
The term ‘sampling’ means taking sample value among continuous analog signal values at regular
intervals.
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