Right PLC for the job!

We are having a new line installed and we have specified to a supplier that all 42 PF40's have their own 22-COMM-E adaptor, ontop of that their will be 12 1734-AENTR's and 1 PV+1500, and we want to then have it connected on the Plant Control Network to interface with other controllers, and monitor the drives and also some Server based SCADA package which has yet to be confirmed, we will then want to do product tracking all the way through the line, they are wanting to use a L3, 1769-L33ER processor now i have reservation that this will be lacking in processing power/connection to do all that we want.

they have also ignored our requests and quoted for 11 ethernet cards to sit on 22-XCOMM-DC-BASE and use RS485 for Run source and speed, the plan is to have 11 remote panels around the line, and in each panel an unmanaged weidmuller switch (IE-SW-BL08-8TX), 1 1734-AENTR and 1 22-COMM-E and between 3-4 PF40's in each, then each box back to the main panel with another unmanaged switch in it.

i have suggested we upgrade to ControlLogix and i emailed the supplier the list below:

I propose a 17 slot ControlLogix rack configured as such:
1756-A17 - RACK
1756-PA75 - PSU
SLOT 0: 1756-L71
SLOT 1: spare
SLOT2: spare
SLOT3: 1756-EN2T (I/O)
SLOT4: 1756-EN2T (DRIVES)
SLOT5: 1756-IF16
SLOT6: 1756-IB32
SLOT7: 1756-IB32
SLOT8: 1756-IB32
SLOT9: 1756-IB32
SLOT10: spare
SLOT11: spare
SLOT12: 1756-OB16
SLOT13: 1756-OB16
SLOT14: 1756-OB16
SLOT15: 1756-OB16
SLOT16: 1756-OB16
And in replacement of the 3 off 1769-IT6 cards a 1734-AENT with the appropriate amount of 1734-IT2I modules which would be located externally from the main panel to suit your system.

the supplier has quoted an extra 17,000 Euro's for this upgrade even though the cost of the upgrade in terms of components is around 7-8k, i could just use 1756-ENBT modules but even with that saving it will take some persuation.

i could do with some advice on if this is overkill going to ControlLogix or if its warranted, and if so some supporting arguments, as the guy in charge of the project is relluctant to spend anymore money on this £12 Million project.


Thanks in advance

Rob

rob upgrading to control logix would likely require a larger encloser which may accuont for some of the difference in price. As for the pv's I would scrap them and go with Ignition from inductive automation and industrial pcs to pefrom the HMI/SCADA/Data base functions as it could save you money while giving you added value. with out knowing the complete scope of the project I could not tell you if the control logix is needed. IMHO

what i was after was any indication that the processor would not be upto the job running that many drives on ethernet and point I/O adaptors.

our standard we sent out with the RFP's were that all drives are PF40's and each having a 22-COMM-E card.

you could be right about needing a bigger enclosure, i have asked them to send me a price breakdown of that, even a larger enclosure surely cannot add an extra 10k to the project.

Rob

i have asked them to send me a price breakdown of that, even a larger enclosure surely cannot add an extra 10k to the project.

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Allot depends on if a P.O. has been issued and work started lets say the compact logix has been bought and installed that money would have already been spent and would be added to the cost. I for one could not sell the then used equipment as new however I would send you the equipment to use or hold them for another project for you as I could not return used equipment. The labor would be lost who would pay for that? new engineering time would be required as well as updated drawings regardless of weather the project had gotten to the build stage. the point a lot of people miss is that its not just the hardware cost that drives the project cost up. In the big scope 10k is a very small increase in a 12mil project.

all that has happened is that the supplier has been selected and now we are finalising the component list, no PO has been given but will be within a matter of weeks.

all of us understand that 17k is nothing on a project this big but the guy who makes the final say thinks that 17k is, as he said before SCADA is not in the scope of this project even though its not SCADA as such its just allowing us the resources to implement a SCADA system in the near future.

my other suggestion would be to allow them to use a compactlogix and they install all the ethernet equipment, then get a stand alone Controllogix in the area and feed all the processors in the area to that and allow that to do the leg work of product tracking etc.

Rob. I like you plan with the Controllogix system. I have one that I am doing now. L71 with 19 PF40's, 1 Panelview plus and a remote L32e using produced /consumed tags. The PF40's have all of the faceplates and AOI's already and are very easy to configure. Your engineering department will be the one that has to live with your system after the contractors are gone. I would also specify that all switches be managed. Another thing to look at is how are you going to drop out those PF40's on an estop. The basic pF40 does not have a safe off option.

Thanks for the reply,

yes i recommended the Stratix 5000 series switch's but they want to just use the standard weidmuller and said could we not fit them ourselves once the kit is installed.

the problem i am having is that they have already quoted us a price for this which isn't in my favour as all the managed switches and controllogix which they then want to add ontop, if these had been factored in earlier before the quote this increase wouldnt even matter and we wouldnt be having this conversation.

this company just do as they please no matter what we request its been a PTA talking with them.

and the guy incharge will be reluctant to allow any extra costs.

im unsure how they are going to do this i have not seen any drawings but maybe just safety contactors in the main panel which feed the remote boxes.

robw53 said:

Thanks for the reply,
yes i recommended the Stratix 5000 series switch's but they want to just use the standard weidmuller and said could we not fit them ourselves once the kit is installed.
the problem i am having is that they have already quoted us a price for this which isn't in my favour as all the managed switches and controllogix which they then want to add ontop, if these had been factored in earlier before the quote this increase wouldnt even matter and we wouldnt be having this conversation.
this company just do as they please no matter what we request its been a PTA talking with them.
and the guy incharge will be reluctant to allow any extra costs.
im unsure how they are going to do this i have not seen any drawings but maybe just safety contactors in the main panel which feed the remote boxes.

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It's Stupid that they are trying to cheap out on the most important part of the machinery. Which is also the least costly in the grande scheme of things. Why even bother asking you what you want if they are just going to throw it away and give you what they want anyways

The old adage is "pay for it now or pay more for it later"

just to clear things up, it is the supplier of the equipment who want us to fit the switches later, the company i work for buying the equipment they are the ones who dont want any increase in the machinery costs even though its the right step

Rob

i agree, unfortunatly i was asked after the quotes had been recieved.

anybody able to advise on the type of connections the ethernet comms card and Point I/O adaptors use, so i can workout if i would go over the maximum supported on a compactlogix?

Any time somebody wants to stretch a CompactLogix into something other than a single machine controller for "cost reasons", I get the same sort of misgivings you are getting.

The same goes for multi-drive mode with PowerFlex 4-series drives: unless you need infrequent speed changes (fans and pumps) you don't want to use multi-drive mode.

The new 5370 series CompactLogix have a simplified way to determine their Ethernet capacity: just count Ethernet Nodes.

The CompactLogix Selection Guide (1769-SG001) has a good table on Page 13.

The 1769-L33ER that your supplier has offered will handle 32 Ethernet nodes; 11 drives, 12 POINT adapters, a PanelView, a SCADA server and a couple of programming computers puts you at about 27.

The larger 1769-L36ER controller will handle 48 Ethernet nodes.

Unless you think of this system as a single machine, I wouldn't accept the CompactLogix to run it.

so let me get this right, each PF40 with an ethernet uses one of the 32 connection on the compacts? i did try using the IAB but this did not really give me alot of confidence and i was supprised when it didnt use any extra, i know the PV+ take up 4 connections and that also doesnt register with the IAB software.

but as usual the bean counters always seam to get it the way they want it, Cheap!!

well im guessing 42 PF40's, and 11 Point I/O adapters wont run happy with a Compactlogix

Rob

AS ken said it really depends on the contrologix or compact logix processor you choose. The new L7 contrologix processor counts ethernet connections differently than the L6 and below for several reasons. The new compactlogix are the same story.

The newer stuff is just count each node not connections.

This is large in part because the new L7 for example supports 500 connections where on L6 series the max was 250.

There are limts on the ethernet adaptor also ENBT,EN2T,etc.

Personally i would not settle for anything less than a L7 at this point because they are jsut as cheap if not cheaper than the L6 series of the same capacity(memory)

If I were looking at controlling that many drives on ethernet I would be looking at the 755 series with embedded ethernet and safe off included to eliminate contactors and **** like that.

I would also be looking at CIP safety if it applies and it will work in almost all cases except the very extreme.

Any company that is not up to par with the above is likely not a company I would want to be doing buisness with. Sounds like they are behind times.

That's food for thought with the 755 series, I think I need to talk to our distributor and find out how much they are in respect to a PF40 with 22-comm-e as any price increase would need to be discussed and higher powers agree it, I didn't even realise the 755 went as low as .75kw, I was asked too late in the project to advice on something's so it's a race against the clock with this one. As well as doing the day job.

+1 Ken's a smart dude with good advice

Ken Roach said:

Any time somebody wants to stretch a CompactLogix into something other than a single machine controller for "cost reasons", I get the same sort of misgivings you are getting.

The same goes for multi-drive mode with PowerFlex 4-series drives: unless you need infrequent speed changes (fans and pumps) you don't want to use multi-drive mode.

The new 5370 series CompactLogix have a simplified way to determine their Ethernet capacity: just count Ethernet Nodes.

The CompactLogix Selection Guide (1769-SG001) has a good table on Page 13.

The 1769-L33ER that your supplier has offered will handle 32 Ethernet nodes; 11 drives, 12 POINT adapters, a PanelView, a SCADA server and a couple of programming computers puts you at about 27.

The larger 1769-L36ER controller will handle 48 Ethernet nodes.

Unless you think of this system as a single machine, I wouldn't accept the CompactLogix to run it.

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