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Hi dear sirs
Our chiller and heat pump's controller use programed microprocessor to do the function.
As I know,most central ac system use DDC to control.And PLC can also do the work.
What the difference between the microprocessor\DDC\PLC and their special advantages?
May be it's a silly question,but I still want professional guy give me an easily-understood explanation. thanks in advance!
best regards
LC
A PLC is a programmed microprocessor, infact PLC means programmable logic controller.
You may want to divide between programmable microprocessors and parametric microprocessors. Eg. most carel's products are programmable, while all but few dixell's products are parametric.
DDC stands for Digital Data controller, and its a sort of building management system that gathers all data for a building and acts consequently. Eg FX16 of Johnson Controls is a multimedia DDC, somehow similar to the pCO line from Carel.
As you see the line between DDC, PLC and other microprocessors is thinner and thinner every day, and by the acronym one cannot identify the type of product.
hello All,
Nonickname is right, the main different between plc and standard controller based on microprocessor is the possibility to develop the algorithm in its own.
Std controller are paramentric so the producer give the controller with a firmware that manage the behaviour according to the paramenter settings given by the user. Plc has still an uP but it enbedded just the bios for the basic function management. Then the user has to create himself the algorithm and the paramenters using some std developing ambient lsaGraf based on IEC61131 standard.
usaully plc has a faster uP suitable into the industrila process, but in Ac market this features of speed is not needed so the price is not justified.
Carel was the first to lunch a programmable low-end controller for Ac market with the Pico but this controller needs custom developing tool provided by Carel and the user must be trained.
Elwell come later but introducing inot a low end controller the IEC stadards comming from PLC world.
This allows to decrease the cost and everyone already able to work with PLC is able to switch easily. So everyone keeps the "know-how" without sharing the information with a software house lnked to Carel
Hi mambro,
Your idea is good. i know Italy Invensys is a good controller for chiler and heat pump which is easily to adapt a special unit to set up the embeded paremeters.
No need to do any programming.
regards
LC
Hi LC_SHi,
other brand are following Eliwell standard, but as I saw now they're still behind.
I gor info the Eliwell is releasing a New product for smal unit to replace Ech series.
I'm gona try it. i'll let you know quickly
Cheers