Question regarding choice of remote I/O

[FrozenFood 0]

first of all, hi everyone! I have been using PLCs for a few years now (CPM2A and CJ1M's) for smaller processes until now. Some context; I am building a system to monitor refrigeration control panels, (all at 230v, but I will be stepping this down to 24v DC) there will be three separate monitoring stations (a CJ1M and a touchscreen) on the site. Each monitoring station will only have to monitor 100~ I/Os and a few dozen PT100's I have to connect a PLC (a CJ1M, preferably) to a remote I/O network of some sort. The context for the project is only monitoring logic 1's and 0's, for now, but i would like to build in expansion so that the touchscreen can be used to turn the refrigeration on or off in the future. the cable run, for the remote I/O will be 300m max. My Questions; What is the best way of using remote I/O with a CJ1M, in terms of ease of setup? The Smartslice remote I/O seems the best choice for this, but what does it take to set something like this up. Like I have said above, i have used PLCs many times before, but this is a step to me and i want to make it as painless as possible. Can someone who has done something similar before give me a few tips? Cheers

[BobB 58]

Have a look at CompoNet. I have started using it and it is very good.

[beegee 7]

We use Sliced I/O on Devicenet. This is easy to set up with CX-integrator and you can connect all sorts of slaves like inverters, other PLC's TCs (even from other brands). On the price side we found it less expensive than Componet (for the moment and our applications anyway) You can go up to 500 m (in a tree network)

[FrozenFood 0]

thanks for the replys! is it possible to connect more than one touchscreen to a DeviceNet network, controlled by one plc? i have looked on omron's website, and they only offer touchscreens with direct serial links to PLCs. does this mean i will have to drop a PLC wherever i want HMI?

[scottmurphy 1]

Not sure about the devicenet, but you can do multiple screens on serial

[chainsaw 0]

I've just used smartslice i/o on devicenet and found it pretty easy to setup with cx-integrator, as beegee has already mentioned. You can have more than 1 HMI on the network, just assign a different node number on the devicenet network. When ordering the HMI you have to specify a devicenet connection as I'm pretty sure it's an add-on to the standard HMI.

[FrozenFood 0]

cheers for that! do omron themselves do screens like that?

[beegee 7]

They used to make it on NT21 and so on... I would consider using ethernet with NS5 instead. You will slow down Devicenet too much with all the data going to the screens and they prbably need the data that is allready in the PLC. I don't like mixing up supervision wit I/O

[chainsaw 0]

I only had about a half dozen screens, so not much data going back and forth. I haven't done a big project on them yet. Does it really slow down comms that much? This would be handy to know for future reference. Erg! Don't know what happened to the quotes, sorry! *fixed Edited 22 May 2007 by PdL

[beegee 7]

NSJ5 can act as a master or a slave on devicenet, but you are putting a more expensive system in place. I would consider using one PLC (coould also be an NSJ) with the remote IO and etherent and conect as many NS screens by ethernet as you want. This will also be an easier topology and all NS screens can be the same (if you don't use an NSJ) with only the IP address different. the speed can be calculated according to the details in the Devicenet manual (W380-E1-03 section 8) but be carefull when using smart active parts they use explicit messaging.

[Nick Clute 0]

I don't know if you require using Omron specific remote IO, and I didn't hear if you liked any fieldbus in particular, but recently I started using Turck's BL67 platform and I like it a lot. They have Profibus and DeviceNet stations, however they also have just straight Ethernet stations that could connect directly to the overhead system instead of running it through a plc...and for any internal logic if you wanted to do some small logic, they have a programmable gateway that is controlled with an IEC 61131-3 language...*shrug* I also liked it because it's IP67, so no cabinet required...