20 micrologix to one Compact logix

[Usireland]

if I used 1769-L33 PLC as main station , the small HMI's will read different tags in PLC (each HMI read 6 bit memory tags for valves state , write 4 integer words) its not big data
Only the Main HMI have larg number of tags and I will connected it via rs232 port with main PLC 1769-L33

Its not really very important if the small HMI´s are reading a small number of tags or a large number of tags it will use a similar amount of Network Bandwidth.

Second the 1769-L33 does not have a Serial port built in. In order to use a serial panel view (which I wouldn´t recommend) you would need to add a 1769-ASCII card. It would be better for you to use ethernet and not add the ASCII card.

I would investigate the 1769-L16ER-BB1B. From memory the difference in price between it and a 1734-AENTR is quite small, it might be worth looking into.

 

[alijuda]

Dear Helliana
Dear Usireland
i thing its more cost to use 1769-XX communication module for each Node ,
Now we just worry from 20 HMI maybe caused network slowly



I will use your advice to use 1769-L36ERM , its support 48 TCP/IP nodes
also when I check the Technical info. for this type I found this notes :

((All CompactLogix 5370 controllers support 256 CIP connections and 120 TCP/IP connections.)) in my case I have 40 TCP/IP connection

according to my plan I will have little problem than using 20 Micrologix PLC+ 1 Compact logix
But I needs your advice ,Iam new with Compact logix I worked before with many Rslogix500 project and Factory Talk vie ME stations , this project the first with rslogix5000
Many Thanks
Ali

 

[Helliana]

Using a micrologix as remote I/O will be a huge headache to develop, support, and maintain. It just just not what they are designed to do. You will kill your network trying to do that many different message instructions plus you have two sets of PLC code, two sets of programming software, etc. for each set of I/O to deal with.

If you want to have all your logic done in one central location, you really need to buy a decent processor that is designed to handle it and use remote I/O that is designed for it. I would recommend one of the L3 series compactlogix models or a low end Controllogix with PointI/O, 1769-AENTR, or a 1756 chassis. I personally like the 1769-AENTR because the wiring is easier, looks nice and clean, and means i don't have to stock but one type of I/O cards.

Your other option would be use a Micrologix or small L1 or L2 Compactlogix to control each machine on their own. This would cut down network traffic for HMIs and add redundancy, but but you would have to maintain 20 separate pieces of code.

If you try to make a micrologix become a remote I/O using message instructions, you are just punishing yourself and making it almost impossible to troubleshoot for anyone working on the equipment after you.

 

[alijuda]

Yes, Iam alreay decided to use Compcact logix main plc 1769-L36E as main station and I study if I can used 1734-xx Point I/O
Its suitable cost for my project I thing this type of PLC Faster than 1734-L33E
For the 20 HMI I will check the network activity if going slowly I will add another compact logix processor and divided the network (10 station in each network)

Best regards for support&early replies