LDmicro Forum - new PLC.

hello Jorge Jacome,

grateful for the compliment, I like to work with quality, soon I'll post some more pictures. remembering that this was not "our" fantastic ldmicro would not be possible for me to mount these PLCs.

Thu Jun 28 2012, 09:19:34

nice work (by bob dole)

how do you make the plastic case
looks very professional

Thu Jun 28 2012, 14:21:47

plastic box (by Magno Medeiros (Brasil))

This plastic box is manufactured by a Brazilian company called Patola eletroplastico. for all I know they also sell to other paises.se tell your parents. see link: http://www.patola.com.br/?pagina=home.php

Thu Jun 28 2012, 15:38:58

(no subject) (by Jorge Jacome)

Hi Magno

Thank you for post patola.com, I was looking for DIN rail
plastic boxes.

About your PLC-- are you using 24 V dc supply for inputs and outputs; the inputs are PNP or NPN, and the outputs are relay type or transitor/FET/MOSFET outputs.

Do you have a PLC version for inputs and outputs 0-10 V and
4-20 ma ?

email: [email protected]

regards

Jorge

Fri Jun 29 2012, 06:27:58

inputs end outputs (by Magno Medeiros (Brasil))

Hello Jorge,

The inputs are digital optical coupling (or MCT6 TLP504).
The 24v relay outputs, as you can see from the diagram that I'm sending.
As for inputs and outputs of the type you described, (analog) have not had time to develop anything, because I work in the department of Electrical and textile industry have somewhat limited time. I think about it for the near future.

Fri Jun 29 2012, 14:08:40, download attachment FPMG DIN 1618 V1 imagem.jpg

(no subject) (by Ciobanu Rivelino)

Hi, you can use ULN2803 Ic transistor array to drive directly from port relays.
That i used for my project.
You dont need 10K resistor & Bc847.
One Ic is for 8 ports.
Regards

Sun Jul 1 2012, 14:58:09

grateful (by Magno Medeiros (Brasil))

Thanks friend, but I can not use this because the CI is very small plastic box, then divide the circuit into four plates as you can see. It would be more complicated in this case. Even so grateful for the collaboration.

Mon Jul 2 2012, 17:39:29, download attachment Sem título.png

(no subject) (by Samukelo Shezi)

Hey Magno Medeiros

Good work, buddy! Can I order that from you? My email: [email protected].

Regards
Samukelo Shezi

Wed Sep 5 2012, 00:26:57

Input stage isolation (by Ziggy)

Hello Magno,

First of all thank You for sharing Your Ideas.

I am looking at the input stage where You are proposing to use optocouplers and dry contacts from external equipment.

Usually the optos are employed to provide galvanic isolation from the external equipment and to minimise conduction of noise from external sources.

Usually this means that the optos are driven from external sources.

Your circuit suggests that the optos are driven by the on-board 24VDC potentially negating any any galvanic isolation benefits the optos provide.

Ah but then they are driven by dry relay contacts thus maintaining galvanic isolation by the virtue of dry contacts.

This then makes optocouplers redundant.

Is my understanding correct?

Tue Dec 25 2012, 03:29:31

CLP. (by Magno Medeiros (Brasil))

Hello Ziggy,

That next year you have peace, health and achievements.
as his observation, thank you, for I see as constructive criticism. I agree in part, but I make use of optocouplers to be standard in PLC's, by using various types of sensors that have digital outputs or dry contacts and because it is common to use relatively long cables premises. Another point to note, is not to expose the microcontroller pin directly to the external environment. I can tell you that in practice have no problems with these PLCs already use on some machines still grateful to you and anyone who makes comments, because I have some knowledge in electronics but am not an Expert.

Wed Dec 26 2012, 08:07:23

(no subject) (by Ziggy)

Magno,

Thank You for the good wishes; may You too have a prosperous and peaceful New Year.

Good to hear the solution is working for You in practice.

I hope to emulate Your success with an ATMega8 based unit.

Presently I have a customer for whom I have designed a prototype controller based on ATmega8. The application is very much an embedded microcontroller solution driven ofcourse by LDmicrosoftware.

I would have normally written this in C ( WINAVR ) but instead decided to try out LDmicro.

It was a breeze.

I have therefore decided to put together an ATmega8 PLC with the view to having an off the shelf solution for odd controls jobs that might come up.

The solution will not emulate the PLC look You have implemented but will rather be packaged in a simple box with cable glands.

I will however go to the expense of separate power supplies to ensure galvanic isolation.

Wed Dec 26 2012, 21:12:02

(no subject) (by Magno Medeiros (Brasil))

ok! I observed some interference at the start, but put some 100nF capacitors in the circuit and solved. I have some PLCs installed at the company I work (textile industry) working well.

Thu Dec 27 2012, 12:54:45

(no subject) (by Alex)

Hello magno, about your PLC design,is it designed for writing the hex program online via icsp, you don{t need to turn the plc off?

Thu Apr 26 2018, 17:12:19

Post a reply to this comment: