recommendations for a nice simple cheap PLC.

[hooey]

Wago controlers

I will throw in the Wago range of couplers and programable controlers I have just finished a small carton conveyor system with a 750-841 programmable controler and found it to be a very capable unit, and i know ther 750-341 ethernet coupler is modbus tcp or ethernet ip slave device.

hooey

 

[dexdyne]

Thanks all for the continued advice.

Of course I meant S7 when I said S5. Slip of the brain.

I'll look at the new suggestions soon.

The stupid thing is that I want so very little out of the device, in terms of function.

Some IOs, a Modbus slave, and the ability to slowly run 100 lines of BASIC would probably fit perfectly - more a modbus remote IO unit than a PLC I guess.

TVM

David

 

[JesperMP]

Look for PLCs that support IEC61131-3 ST "Structured Text" language.
It is more close to Pascal than Basic, but should be very easy for a Basic programmer to get into.
I know that at least the Beckhoff PLC can do this.

edit:
Wago can.
S7-200 cannot.
S7-300 can (but way too expensive, even more so with Modbus).
AD cannot.
AB Micrologix cannot.

 

[Trance-M]

Have a look at VIPA plc's.
http://www.vipa-automation.co.uk/

http://www.vipa.nl/contact/vipa-worldwide/

They are cheap compared to Siemens, but you can program them with the Siemens Step 7 software.

All VIPA systems are programmable with STEP®7 from Siemens or with WinPLC7, the programming tool from VIPA. The VIPA systems 300S and 300V are designed for compatibility to S7-300® from Siemens enabling mixed operation, e. g. with CPUs from VIPA and modules from Siemens. Systems 100V, 200V, 300V and 300S offer solutions for centralized and decentralized applications. For centralized use a variety of CPUs is available. Depending on the type, the CPUs of systems 200V, 300V and 300S are equipped with an integrated CP 343 for communication via Ethernet. As a standard, the CPUs in system 300S are equipped with an Ethernet Interface for PG/OP communication. For decentral applications, CPUs with integrated Profibus DP SlaveInterface as well as ProfibusDP, CAN, INTERBUS, Ethernet and DeviceNetSlaveFieldbusCoupler are available.

10.10.07 - Category winner at Innovation Prize 2007 The German “Initiative Mittelstand” has awarded the Innovation Prize 2007 to our product “SPEED7 – Fastest Hard-PLC in the world”.

 

[JesperMP]

Actually, what is it in that Basic program ?
Unless there is a lot of string manipulation, then you can probably use any PLC with Ladder ot other traditional PLC language.
Ladder is easy to get into (biased opinion obviously). You can probably write the same Basic program in Ladder with just a little bit of effort.
You can get an AD DL05 for around 100 USD with 8 in, 6 out + modbus slave.

 

[dexdyne]

> Actually, what is it in that Basic program ?
> Unless there is a lot of string manipulation, then you can probably
> use any PLC with Ladder ot other traditional PLC language.

Absolutely. I was using the expression 100-lines-of-basic to show the size of the complexity. Ladder, ST, C, whatever will all do it.

> Ladder is easy to get into (biased opinion obviously). You can
> probably write the same Basic program in Ladder with just a little
> bit of effort.

One day I must master it, so you're right.

> You can get an AD DL05 for around 100 USD with 8 in, 6 out + modbus
> slave.

OK - I've obviously failed to notice that. My notes said DL05 was $99, but modbus expander D0-DCM cost an extra $129. PLus $400 for the programming s/w

 

[JesperMP]

As far as I understand, it supports modbus directly on both onboard serial ports. I could be wrong though.

 

[72hdflh]

Yes, the DO-05 does support Modbus directly through both onboard ports, check out chapter 4 of the manual Chapter 4 Page 33 in the following link. http://web4.automationdirect.com/static/manuals/d0user/d0user.html

You can also download a free version of the software, however it is limited to 100 words.

Hope this helps.

 

[milldrone]

it supports modbus directly on both onboard serial ports.

Jesper , You are correct, rs232 but that should not be a problem at 5 feet. The free demo software will program up to 100 words. A while back I was helping someone who could not purchase the software and needed to use the demo version. This worked out to 18 uncomplicated rungs.

 

[chud]

Why not just go for a Zelio(Schneider) or a Logix relay (Siemens)
Can program in Ladder or Function Block Diagrams and is quite powerful for such a low end unit.

Meets all ur requirements except for C language.
Can do coms with a HMI and coms via Cellphone