Siemens Logo (is it a PLC?)

[Johnny Rotten]

Hope this topic has not been covered, anyhow will be taking a one day course on Siemens Logo. Course includes software and hardware (to take home and keep). Siemens calls this a smart relay or something like that.

Is this Siemens answer to AD? Has anyone actually used this stuff? I've never heard of it, and Logo sounds way too much like Lego.

Any thoughts?

Johnny

 

[mday]

The Logo has been around for a number of years, it's positioned to replace timing relays and other single function relay devices with it's cost and high current outputs (10 amps). It programs with FBD or LAD and offers a number of instructions to develop your application with.

My Dad carried a few Square D multifunction timing relay around with him that he purchased for $100 each, but now keeps a few Logos with him instead. The Logo offers him more flexibility and cost just a little bit more than a single timing relay.

Good luck!

 

[Johnny Rotten]

Thanks Micheal. Obviously you can not send analog to anything (a drive speed reference) because the expansion mod's are only analog in. They do not make an analog out mod.

Oh well, can't wait to play with one. Oh yes the course is $200.00. Will get to compare this LOGO with a AD D0-05AR and a AD D0-06AA.

Can't wait for A/B's reply. Maybe the DooDoo?

Johnny

 

[Tim Ledwith]

John,

My understanding is that the LOGO is a "smart relay" as opposed to a full blown PLC. I mostly use the Allen-Bradley Pico relays for applications where I don't need a full blown PLC. However, recently I have started using more LOGO relays - the add on Analogue Input and PT100 Input Modules have come in useful on some applications.

Most PLC manufacturers have got a smart relay in their product range, check out the Omron Zen Relay, the Moeller Easy Relay and the Telemechanique Zelio Relay - some of them look suspiciously similar to each other.

Another Relay you could consider is the Mitsubishi Alpha Relays - I have used these on several small automation projects.

Regards, Tim.

 

[Johnny Rotten]

Mday and Ted, sounds like a proper way to make a mess.

It must go deeper than that. How do you use these on profibus?

Johnny

 

[dchartier]

Hellow Johnny;

Basically, you don't (use it on Profibus). It is not a PLC, it is only a Smart relay: no memory or interfaces for comms are included in the package.
Hope this helps,
Daniel Chartier

Edit: let me rephrase that: there is connectivituy available from a Logo! relay to a EIB bus (buiding automation) and (although limited by the number of I/O) on a As-i bus.Basically, exchanges that require only bit-level access. Nothing for Profibus, Modbus, or other control automation buses.
D.C.

 

[Johnny Rotten]

Thanks DChartier. Still sounds like a proper way to make a mess.

When it fails, which it will, replace it with...?

Just sounds like a Siemens 1-800 call.

Again, sounds like a proper ...

Johnny

 

[Eric Nelson]

Hope this topic has not been covered...

Actually it has (sort of), in THIS thread, but it can't hurt to bring it up again. These smart relays have their uses, but you really need to understand their limitations before using them. I've used them (the Moeller Easys) on a few simple projects. Stand-alone level control, shift register, etc...

My biggest gripe is the limited number of timers. There's only 8 in the Easy...



-Eric

 

[ArikBY]

I stopped use them since I started to use AD,DL-05 do every thing better then this smart relay,and it is real PLC with out the limitation Eric mention.
It cost about a same.

 

[scairn]

john

ihave used klockner moeller easy relays for a number of years the new 800 series allows you to input 2 anolouge signals and one output (0>10 V dc). they are priced around $500au the programing is via easy soft pro or through the buttons on the front of the unit. it uses a combination of ladder logic and FBD. they work as good intermediate from relay logic to a full blown plc

 

[whish1]

help understanding the logo

I stopped use them since I started to use AD,DL-05 do every thing better then this smart relay,and it is real PLC with out the limitation Eric mention.
It cost about a same.

************************************************************

http://support.automation.siemens.c...iew/en/24786764



https://www.automation.siemens.com/...tml?HTTPS=REDIR

Hello guys does anyone mind giving me a short tutorial ?
The links above are for the siemens website application examples for the logo 12/24Rc
Of interest to me is the program example for
1)*Heating Control*
2)And scaling of 4-20mA sensor
3)Storing Analog min max values

I dont understand what the symbols used in the FBD mean and what they are doing there .
If you can spare the time I would appreciate it.

Regards

Wayne

 

[dchartier]

Rtfm

Hello wish1;

Even better, I can suggest the following link:
http://support.automation.siemens.com/WW/llisapi.dll?func=cslib.csinfo&caller=view&lang=en&siteid=cseus&aktprim=0&extranet=standard&objid=10805245&DataKey=10805245&treeLang=en
You should find all required info here.
Hope this helps,
Daniel Chartier

 

[Doug_Adam]

We use the occasional Logo, this is usually where we would otherwise use hard wired relays.
The latest Logos now have maths and other functions missing from the earlier models. I think they are now in the bottom end PLC area.

Just as a comparison, they are more capable than a late 70's vintage TI that we had at my previous company.

 

[Crossbow]

Logo does in fact have analog output capability, which someone earlier said it does not.

And www.siemens.com/logo has plenty of information, manuals, and sample programs.

The one day Logo training with the starter kits is something I used to teach all the time when I worked for a Siemens distributor. You get the starter kit and some basic training, which I think really helps people understand what Logo is and what it isn't.

I've personally been responsible for around 300 Logo sales (about 270 of those were a repetetive control panel) and wrote the programs for most of them. And I have one controlling my pool pump and outdoor lights.