Function blocks for PLC500
Hello Rob,
Query is:
As we use following Function Blocks in our Control Builder for AC800m :
1) "SignalInReal" : for Creating alarms, etc for High Level , High High level,etc
2) "IntegratorReal" : for Totaliser function Block.
So, as I have now just started working PLC500. I couldnt find the equivlent Function Blocks here.
Can you please suggest them ?
Voted best answer
They dont exist. Write them yourself.
The AC500 is a simple PLC with limited memory compared to the AC800M. So writing a fullly featured SignalInReal block with alarm handling, limit checking etc will waste memory and CPU time calculating things you never actually need.
The AC500 is IMHO a great little PLC - but it isnt an AC800M. Keep your AC500 code SIMPLE ! Write only the functions you need - eg for analog handling just scale the Input Channel to a real value as required and use that. Write only the compare functions that you need for limit checking on idividual signals, not every signal. Your motor controls do not need to be any more complicated than a SR for command output and an AND to check ready/running. A totalizer is just an ADD block and a MULT to scale the input for signal range and program scan time.
All of your alarm handling, operator presentation etc goes into the SCADA. Since you already said you are using 800xA then you can build all of this functionality much more easily in the object types.
Use the KISS principle... Keep It Simple Stupid :)
Answers
Also, check the Util.Lib library for the basic components you can use.....
Analog Value processing -> LIMITALARM
Mathematic Auxilliary Functions -> INTEGRAL
There are a lot of FBs, LIBs and APPs for the AC500. Some of them are available for free download. Some complex libraries are with a licence. Please frequently visit or subscribe for alerts here:
http://www.abb.com/abblibrary/DownloadCenter/?showresultstab=true&categoryi
d=9AAC177033
You can also find the path from www.abb.com/plc
Best Wishes
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