Siemens Vs. Allen Bradley

Hey all,

We’re looking at moving our in house automation platforms away from Mitsubishi to either Siemens or Allen Bradley. We’ve been doing a lot of research and are starting to form some opinions but I’d like to hear from other people about what their experiences have been between the two.

We have dealt with Allen Bradley in the past and they have been somewhat lacking in support, plus we aren’t a big fan of all of the firmware revision stuff. However we haven’t had much experience with Siemens so I can’t say for sure how they directly compare.

What do you think?

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I can’t give you a good integrator/end-user perspective on it… but from a driver compatibility standpoint, at least with our drivers/server, AB wins hands down.

We are planning to use Ignition S7 driver for communication with S7-400 PLC with an important load of IO communication : 7 PLC S7 with 10000 io tag for each PLC.

Do you heard about big architecture with the S7 drivers ?

S7 driver support only direct adressing, what is the principle for request optimisation ?
(we plan to acces only DB data)

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my opinion is that AB software is far better, especially if you are using rslogix 5000. Its been a few years since I messed with any siemens plc’s, but I found AB to be much better.

Hardware wise I think either is good.

Another thing to look at is how willing your local distributor is to help you out.

In the UK, there appears to be a distinct love or hate relationship with Siemens. You either love it or hate it. I’m sure that this is down to the previous versions of programming software. Siemens have made a significant improvement with the latest version of software (TIA portal) which has made this much more user friendly. They also allow the use of all of the IEC programming languages on the higher specification PLC’s.
From a hardware perspective I think they are as capable as one another and both have significant amounts of programming memory and rediculously fast scan rates.
Firmware updates on the CPU units are free to download from the Siemens website as required.
I guess my preference would be to use Siemens as they natively support Profibus & Profinet and AS-interface which would be my fieldbuses of choice, even at the low level processors and have the option of ‘Integrated Safety’ PLC’s

Obviously from an Ignition point of view there is no direct access to the PLC tags, with Siemens but I’ve not found this to be an issue.

Go over to this forum , this topic and “Which PLC is best” have many discussions.
Consensus is North America = Rockwell , rest of world = Siemens

plctalk.net/qanda/showthread.php?t=79004

best thing I like about Contrologix, with a the Ethernet card in a Clgx rack that has other network cards, (C-NET,DNET, DH+) you can connect to any device on other network across the backplane of the Clgx rack just by connecting to the Ethernet card.

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Thanks guys, all good info.

I will point out that we’ve narrowed our choice down to Allen Bradley and Siemens specifically because we need products that can withstand corrosive gas environments. Both Allen Bradley and Siemens offer these products (so does ABB, but they are VERY far behind in both hardware and software).

Price wise, Siemens is cheaper for both hardware/software and support. However, we won’t mind paying more if the product and support is of higher quality. The biggest thing that irks me about AB support is that the tech connect contract stuff goes up in price depending on how many CPU’s you have out on the floor. Why should I have to pay more for software support because I install more hardware? Especially when the hardware price is almost double the next leading competitor.

But I digress… In the end price doesn’t matter so much as long as you get the quality you pay for. I’m more concerned that the hardware holds up and that the ease of use is there. Bottom line is that we don’t want to be in the same situation we are in now in another 10 years.

I appreciate the perspectives, keep them coming!

[quote=“Duffanator”]Thanks guys, all good info.

I will point out that we’ve narrowed our choice down to Allen Bradley and Siemens specifically because we need products that can withstand corrosive gas environments. Both Allen Bradley and Siemens offer these products (so does ABB, but they are VERY far behind in both hardware and software).

Price wise, Siemens is cheaper for both hardware/software and support. However, we won’t mind paying more if the product and support is of higher quality. The biggest thing that irks me about AB support is that the tech connect contract stuff goes up in price depending on how many CPU’s you have out on the floor. Why should I have to pay more for software support because I install more hardware? Especially when the hardware price is almost double the next leading competitor.

But I digress… In the end price doesn’t matter so much as long as you get the quality you pay for. I’m more concerned that the hardware holds up and that the ease of use is there. Bottom line is that we don’t want to be in the same situation we are in now in another 10 years.

I appreciate the perspectives, keep them coming![/quote]

The pricing of Tech Connect is based on # of activations, not CPUs .
It is sold in increments of 1, 5 & 10.

We pay $7K for 5 activations per year. Pricey, but costs can be easily implemented in to large contracts, also keeps you up to date on all hardware and software.

We used to be a Siemens house, thing that irked me about Siemens support was the response time.
Support cycle was like this:

1 - call tech support # and leave a name , contact info
2 - within an hour or so , someone would call back and get details and decide why type of support required
3 - within a few hours or next day, tech person would call you back.

With Rockwell support, if you called you usually were talking to a tech within 5 - 10 minutes.

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I think whatever Siemens does becomes a standard in Europe like Profibus, profinet even opc is originated with support from Siemens. So Your decision should also be based on your customer location as well !