A bit of Advice on which PLC, Automation Direct?

[jstolaruk]

And he doesn't know A/D. So his learning curve would be the same.

 

[DwSoFt]

I'm assuming he is revamping the system bc the client doesn't like the existing Siemens setup for whatever reason

 

[JRW]

The end user doesn't know it either.
And doesn't have the original code.....
A vicious circle

 

[Edmhydraulics]

I am not going to use the S7-300 plc currently in the machine because it's obsolete, the customer is spending money to upgrade the machine, I don't want to put legacy equipment in place when I have the option not too. Second reason is that yes I don't know Siemens, I have heard it's not the easiest to learn, also I don't want to pay the $1800 for the software which is pretty much the cost of the Do-More which looks to have great help and support and free software.

 

[jstolaruk]

I am not going to use the S7-300 plc currently in the machine because it's obsolete, the customer is spending money to upgrade the machine, I don't want to put legacy equipment in place when I have the option not too. Second reason is that yes I don't know Siemens, I have heard it's not the easiest to learn, also I don't want to pay the $1800 for the software which is pretty much the cost of the Do-More which looks to have great help and support and free software.

I see S7-300 series stuff still being shipped on new equipment so I wonder about the obsolete reference. And having used both A/D and Siemens, I have to respectfully disagree on saying that its an "upgrade". The savings from not purchasing new equipment would pay for the s/w. And you'll have a s/w learning curve no matter which platform you choose.

Interesting you mentioned IEC61131-3, I haven't found a claim for compliance with the Do-More product. Step 7 (TIA) is.

But hey, in the end you have to support it so its nice not having to follow a narrow specification.

 

[Edmhydraulics]

I was told the S7-300 was obsolete or going to be soon, perhaps that is wrong, I dont know. I just have a sneaking suspicion that the S7 will be harder to learn than Automation Direct, I have experience programming in Ladder, so it should not be too bad. I am more familiar with 61131-3 compliant systems, but like I said I can do straight ladder as well. I want to have the backup of good customer support, and a good website to fall back on, I dont know how well Siemens is supported out here, and from what I have seen their website is not that good. Ultimately I would like to add Siemens to my repertoire, but not on this project. If I can get the S7-300 from this job and use it to work to learn Step 7 then that would be good.

So

 

[DwSoFt]

I haven't seen many Siemens in Alberta. But I have seen a few. An Osb mill is 1, power generation skid was another. I think it's mostly when packages come here from Europe.

 

[Edmhydraulics]

Funny thing this machine I am working on was made in the US. And came complete with Siemens HMI and PLC.

 

[JRW]

Should be easy to get the source code then
You need to get out more, Siemens is all over the US.
It's not a little company just in Germany

 

[Edmhydraulics]

We tried to get the source code from the manufacturer, he won't give it up or do the changes required so we are back to square 1. I realize that Siemens is huge worldwide, just that we don't see much of it here in Weatern Canada, I think the learning curve would be too steep to learn Step 7 in a short period, where it looks like there are lots of tutorials available on the AD product. I would love to know Siemens product, but it's one of those things for the future.

I am also building a line of machines that hopefully be able to export, so that would most certainly be using Siemens product, but I need orders from overseas first before I embark on transferring the programs over. As it is all my sales so far have been in Canada and the US.

 

[keithkyll]

Over the years of building custom equipment, the customers liked to specify their preferred brand of PLC. I've had to learn Idec, Omron, TI, GE, etc. When the choice is mine, it's mostly AD.
Recently had a big project where Siemens was specified. Software was TIA13. TIA is Totally Integrated Software. PLC, HMI and other software packages are combined into one interface. You need a powerful computer with lots of memory to handle it.
I did a distributed control system with six S7-1200's, and an Industrial computer from Siemens.
The learning curve was horrible. There was quite a few bugs. The best support was on this forum. The hardware is well built. I liked canned features like the boxes (FB's, Function Blocks) they have for serial communications.
Programming the HMI was very time consuming. It takes several steps to create a pushbutton.
The customer purchased a machine from China, and specified Siemens to the builder. They built it with a S7-200 and 10" HMI. Both were built for the China market only. Not programmable or supported here. Siemens made that clear. We had to tell the customer he needed a S7-1200 to replace his S7-200, and a new 10" HMI as well. After trying to deal with a hot customer who found our story hard to believe, our vendor had to explain it to them. Next, find a way to upload the program from the S7-200, and convert to S7-1200. Needed a copy of (obsolete) MicroWin. After that, found there wasn't a S7-200 to S7-1200 converter in TIA13. It was offered in the first version of TIA - 10.5. Had distributor do the conversion. It was so bad, I couldn't use it. Fortunately, the program was small so the rewrite wasn't too bad. At least I had the Modbus codes they used for the VFD's, and that's all I needed.
Talking to 3 VFD's via RS485. New program was running fine. Over the weekend, the RS485 module quit communicating. Power cycle was the only way to reset it.
Used six Modbus FB's. Three for Read, three for Write. Used the "Done" bit from each box to advance sequencer to the next FB. Added fault counters, and watched the counts rack up. About 20 per minute. Turns out the "Done" bit was little early, causing crashes on the RS485 bus. Added a 500 ms delay between each FB to cure it. Tested it all the way down to 10 ms without faults. This exact method worked on the Chinese S7-200, but not the replacement S7-1200. Guess the new PLC was faster. Siemens never answered my question about the timing issue, or why the CPU in the RS485 would lockup, and no software commands would reset it. PLC's Link.

The dumb Ethernet switches from Siemens should be plug and play. Has a pushbutton for setup, but this is only to configure the fault lamp according to the manual. During testing, I couldn't get the switch to communicate with the PC. After contacting Siemens tech support, they said there was an issue with the setup switch. You need to push it several times until you get a specific flashing light pattern. If it's still in "setup" mode, it can appear to be defective when it's not. Not documented in the manual, or on their website. PLC's Link.

An address limit nightmare that JesperMD was able to help me with.

WinCC Datalogging issues. Had to write a custom in VB.

One day, I installed an additional RS232 module, but it had an error. Turns out the TIA update added new default drivers that weren't compatible with my 6-month-old modules. From Siemens support:
-----------------
"In V13 SP1 when you pick the 241-1AH32, then look down at the bottom under 'information' and you can see by default it is selecting firmware version 2.1. If your module is version 2.0, then selecting it as 241-1AH32 firmware 2.1 won't work.
You need to click the pull down and select it as 2.0 before pulling it over to the cpu's left side."
------------------------------
So the new 2.1 driver is not backwards compatible. Nice.

AB is the big one in the USA, Siemens in Europe. I didn't have any trouble with AB. Perhaps Siemens was good before they went with TIA. We have quite an investment in software, a starter kit, and a couple of PLC's and modules. We'll probably put them on eBay. I doubt that Siemens will ever be my first choice. There was just too many issues that I found hard to excuse.

 

[Edmhydraulics]

KeithKyll, thats those are the type of issues I am concerned about. Siemens is a huge worldwide company, their product is used in high reliability critical infrastructure, stuff like nuclear centrifuges from what I hear(see Stuxnet). Do you think they really care about one integrator trying to set up a system for a single machine, they are after the 1000's of machines market.

AD looks like they work well with the small to medium sized OEM or Integrator, their website is easy to navigate and its easy to find what you are looking for, they have a multitude of videos on YouTube that you can watch, and it looks like they have a loyal following in North America.

I am not knocking Siemens, some large companies here do specify their components, but its more than what I need right now.

Cheers.

 

[jaden]

From my experience, the support from Automation Direct is second to none, especially for smaller volume users. And, I don't have pay for a yearly support fee.

 

[JRW]

Edm
Get the project, get it done and make some money
That's all that counts

 

[Edmhydraulics]

JRW, Yup, thats the plan, I have the project, I just need to get it done.