Which AB PLC???

Just looking for some advice on which AB Plc to go for.

The process has 500 I/O, All the I/O is in panels but will be split up into two with a remote rack. All the I/O are Digi and relay output with the execption of 8 analoque ouputs and 4 drives.

Also I will have 2 hmi's and about 4 drives. They are local to the panel but not sure on which network to use.

I have allways used Mitubishi but we have two systems on site that have the compact logic L35E so I was thinking of going down the same road.

However I'm not sure if I should go for the control logic range.

So just wondering which range is most popular amoungst professionals compact logix or control logix?

Andy

My take on what distinguishes a ControlLogix over a CompactLogix:
I would say go CompactLogix and all ethernet, but AB's odd product family tree forces you to choose between devicenet, or select a different hardware family for the remote i/o.
There is an 1769-ADN adapter for putting 1769 i/o as remote racks on DeviceNet, but nothing like that for Ethernet/IP (as far as I know). Really strange, as it would have fitted nicely with the Ethernet/IP port on the 1769-L35E.

To my opinion, when you are making a strategic decision about which new PLC platform to use over the next many years, chose the one that is based on Ethernet if you can. Profibus and DeviceNet are not bad choices, but 10 years from now they will be less important than they are now.

So I think you have these options to choose from:

• CompactLogix CPU and i/o + DeviceNet adapter + CompactLogix i/o on DeviceNet.
• CompactLogix CPU + Point i/o on Ethernet/IP.
• ControlLogix CPU + ENBT adapters + ControlLogix i/o on Ethernet/IP.

I'd suggest going with ControlLogix, especially if you will have potentially multiple communications networks.
To save some money, you can use 1734 Series Point I/O for the remote rack, which can be MUCH less expensive then a full 1756 rack.

I would say go with CompactLogix and 1794 Flex I/O for the remote panel. The Ethernet adapter for the Flex is 1794-AENT.