LSIS XGB Series, Руководство пользователя

Страница: 364 / 618

XGB Analog edition manual
10.6 Functions of Analog I/O Option Board
The functions of XBO-AH02A analog I/O option board are as follows.
Function Description
Channel
operation/stop setting
● Specify operation/stop of the channel which will perform A/D, D/A conversion
● Specifying unused channels as Stop can shorten overall operation time.
I/O Voltage/current
range setting
● Specify desired range of analog I/O.
● Select voltage/current with external switch, and set up range with parameter.
● Analog I/O option board provides 2 ranges(4~20mA, 0~20mA) of current I/O and 1
range ( 0~10V) of voltage I/O.
I/O data type setting
● Specify digital I/O types.
● This option board 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, it processes sampling.
● Averaging process
- Outputs A/D converted value averaged by count to reduce rapid change of input
value caused by external noise
D/A output status
setting
● When switching form RUN to STOP, it sets output status of channel
● Provides 4 types of output status (former, min, middle and max value)
10.6.1 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.
.
10 - 12