why the SCAN time of DCS is more & that of PLC is less? if the SCAN time of

why the SCAN time of DCS is more & that of PLC is less?
if the SCAN time of DCS then why we use DCS.

Question Posted / gaurav.r.kale@gmail.com

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why the SCAN time of DCS is more & that of PLC is less? if the SCAN time of DCS then why we use..

Scan time of DCS is more than the scan time of PLC when the
I/O's are digital.
Whereas the scan time of DCS is less than the scan time of
PLC when the I/O's are analog.
Hence DCS is better when analog signals are considered
whereas PLC is better when digital signals are considered.
However DCS do handle both analog and digital signals. It
can also have more no. of I/O's compared to PLC. Hence we
use DCS.

Is This Answer Correct ?

33 Yes

7 No

why the SCAN time of DCS is more & that of PLC is less? if the SCAN time of DCS then why we use..

Answer / kyle condran

DCS are not PC based. the configuration and operating software are but the actual control happens in a control module. DCS usually have a fixed scan time 50ms+, but not always, regardless of I/O count or program size.

PLC scan time depends on Program size and I/O used in the program.

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5 Yes

0 No

why the SCAN time of DCS is more & that of PLC is less? if the SCAN time of DCS then why we use..

Answer / solomon

Eventhough PLC scan time is less,DCS is selected for its
I/O availability.About 1 lakh I/O available in DCS.

Is This Answer Correct ?

11 Yes

10 No

why the SCAN time of DCS is more & that of PLC is less? if the SCAN time of DCS then why we use..

Answer / k.k.rameshkumar

DCS is pc based system. The speed of the processor/CPU
decides the scan time.

Is This Answer Correct ?

3 Yes

28 No

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