What is a good programmable relay?

[mr_electrician]

Quick question here. Has anyone used a programmable relay such as LOGO, that has more then 16 output capability, such as LOGO! Edited April 7, 2007 by mr_electrician

[beegee]

every brand has its own prog. raly but many come from the same factory Logo seems to be one of the better, just like the Miillenium, Zelio, ZEN, Easy.... I don't know the exact specs of each but I think you can't afford to dig in deep into the specs for those prices Edited April 5, 2007 by beegee

[Ken Moore]

I've used the TECO unit the last few applications, because of the low price compared to Siemens or AB. http://www.factorymation.com/s.nl/sc.2/category.22/.f The standard size only has 12 outputs, and there are 4 output expansion modules, I don't know if you can add more than one expansion module at at time or not. Call the dealer in the link and ask.

[JRoss]

The Mitsubishi Alpha 2 is the only one I'm familiar with. The largest unit has 15 inputs and 9 relay outputs, and you can get extension blocks with four outputs, either transistor or relay. If you're looking for a large number of outputs, you might want to look into a full PLC with relay outputs, such as the Mitsubishi FX1s or FX1n. Those come with more options and expandability, and for a large number of I/O would be comparably priced, or even cheaper.

[entertron]

Mr. Ashton, When you start getting into a greater number of I/O, I would suggest a PLC instead. Smart relays offer limited internal capablities and programming capacity. They are what they say they are...a relay with some additional intelligence, compared to a relay itself. If there is a PLC you are familiar with, I would suggest looking at what they offered...you had mentioned Siemens, therefore the S7200 will be more than capable of handling your application. If you are open to other products, there are many to choose from, including ours. Much will depend on your application. Hope this helps. God Bless,

[Crossbow]

By far in my experience the Logo is one of the most expandable and easiest to program. So if you're beyond that, then the best bet by far is moving up to a PLC. Logo's a simple device. BTW many vendors sell the exact same product. Check a Siemens Logo against an Idec Smart Relay. Idec told us they get them from Siemens. Typically their unit lags a version behind though.

[mr_electrician]

I would buy a small Step 7 200 plc, but it is the company that won't fork over the money for one. Thats why I have been using LOGO's. But as we all know, it will max out at 16 outputs. I have rewired some common spine conveyors by cascading the contactors off on output, but I am still stretched. I think I am going to add a second LOGO into the system and use my last spare output from the original logo to enable the second LOGO controller. The main issue also is that the conveyor system layout is temporary. When we get the final layout, I will devolope the electrical system WITH a plc. What a learning experience so far!!!!! Edited April 7, 2007 by mr_electrician

[Crossbow]

Too bad they won't spend the money now. If you had the PLC in your temporary setup, it would serve several purposes. 1. You wouldn't have to buy it later and buy Logos now (so the money thing seems like a lame excuse) 2. You could begin getting more familiar with the PLC programming now. 3. Some of the code you write now would probably be reusable when you finish the project. Take those arguments to management and see what they say. They're wasting man hours developing it two ways.

[Gazzr]

Can't you just tell them that the project you are being asked to do is beyond the capabilities of the Logo. (This wouldn't be a lie). If they want the system they must take the step. Don't offer the solution of using two Logo's, and going back to using the auxiliarly relays on contactor's is a step backwards. I recently convinced my employer that the S7-200 was the best next step for the small projects in my company, (allthough my manager is quite an easy going guy who gladly let's us get on with it). I bought the "Starter pack" or whatever they call it, and it worked out to be fantastic value for money. Also this would be a great next step for you, as it is a bigger step than I first expected but you are probably like me and most people on here, eager to learn.

[gravitar]

If your company's concern is having to pay for stuff NOW that won't be used till LATER, you should talk to your siemens salesman about your problem and see about getting extended terms.. Like net-60 or net-90. Depending on your company's sales volume and payment history, it shouldn't be a problem. they might even have a sales loner you could do your development work on.

[mr_electrician]

We are on net 60 with our SIEMENS supplier. Work figures that I can make it work with what I have, and I can, just don't agree with it.