Siemens S7-400 ユーザーズマニュアル

ページ / 638
Interface Submodules
13-44
S7-400, M7-400 Programmable Controllers Module Specifications
A5E00069467-07
13.7.4
Conversion Time and Cycle Time of the Analog Input Channels
Introduction
This section contains the definitions of and relationships between the conversion
time and the cycle time of analog input modules.
Conversion Time
The conversion time consists of the conversion time of the analog-digital converter
(ADC) and the settling time of the multiplexer.
Cycle Time
Analog-digital conversion and transfer of the digitized measured values takes place
upon request or by way of multiplexing (parameter assignment required), that is the
analog input channels are converted in sequence one after the other. The cycle
time, that is, the time until an analog input value has been converted again, is the
sum of the conversion times of all analog input channels of the interface
submodule.
Figure 13-22 gives a breakdown of the cycle time for an four-channel analog input
module.
Conversion time channel 0
Conversion time channel 1
Conversion time channel 3
Cycle time
Figure 13-22 Cycle Time of the Analog Input Module