I have one final question please.
Will I require an additional modified ribbon cable to allow a Raspberry Pi Touchscreen to be connected to UniPi?
I have one final question please.
Will I require an additional modified ribbon cable to allow a Raspberry Pi Touchscreen to be connected to UniPi?
@jaroslav_sobota:1x8mbc8a:
If you wish to receive a complete package with REX installed, you have to wait for the official reply from the UniPi guys.
Yes I think this is the way to go, The UniPi Industrial kit + REX advanced installed ready to start working on & programming.
@iot:28op1ppj:
Hello,
as you easily can see here - it cost's less more money (35$ => 84$).
So is the total cost of UniPi Industrial set €229.00 + $84?
I have just one more question before I can proceed with a proposal to present to the directors.
I understand that the UniPi industrial system is supplied with standard REX for Raspberry Pi, however I would need to use the PIDAT function that is only supplied with the REX Advanced for Raspberry Pi.
What is the total cost for UniPi Industrial if it is supplied with REX Advanced instead of REX Standard please?
@jaroslav_sobota:5etmpkxr:
So for approx 479 GBP you have a solution which I believe completely replaces the Omron PLC and gives you much more potential.
Firstly let me thank you for your research into my thermocouple problem, however 479 GBP is only slightly less than the Omron equipment cost after our discount has been applied. I agree that Pi would give much greater flexibilty but i still have to reduce costs as much as possible to help off set the development costs of the project.
As i mentioned the only real problem was the use of a thermocouple and i think i have found an alternative solution that i would like to show you.
http://www.yoctopuce.com/EN/products/us ... ermocouple
This unit supports Pi via the USB interface and looks to be exactly what I need to progress this project with Pi & UniPi.
Jaroslav, I would greatly appreciate any feed back about this that you may have.
@jaroslav_sobota:1j6te3ge:
Can you put here a link to the datasheet of the Omron PLC and I/O modules you are trying to replace?
What load are you switching with the SSRs? AC or DC current?
What sampling frequency and precision do you need for the analog input (pressure transducer)?
What is the price of the current solution with Omron PLC and HMI?
This is the PLC http://uk.rs-online.com/web/p/plc-cpus/0401589/
We are switching a 220V ac load on all four SSR's
A sampling time of .5 seconds will be ok and precision of 1 integer (no decimal places)
The aporoximate cost, for these components can be calculated here
http://uk.rs-online.com/web/p/product/7 ... wwod3h4IGg
@jaroslav_sobota:3ruvvmme:
I'm not aware of any other solution. You might be interested in the RIO-2018 Modbus module, which you can use to read thermocouple data.
http://www.artila.com/en/news/news-2015-05-15.htmlHow many thermocouples and other I/O are you using in your machine?
This project is as much about driving costs down and increasing flexibility of the machine as much as possible, for example displaying and printing the machines production cycle information and operating parameters, network connectivity etc.
As the machine stands at the moment I have 2 switches(start & stop), one thermocouple (K-Type), one pressure transducer (0 to 10v) and 2 inputs from micro switches, and 4 outputs to SSR's & 1 HMI, at the moment we are looking into replacing the Omron PLC & HMI, replacing these with Raspberry could save up to 60% of the electrical components costs per machine.
ideally I would like to have everything except the touchscreen mounted together and in a modular format, Having the odd printed circuit board floating around and pieces of breadboard will not be acceptable.
My role is software engineer, and I would like to use the Rex control system for programming but electronics is not in my or our service engineers skill set, if a part fails we need to replace the defective module, not get the soldering iron out.
If I can get this small project started I have no doubt that is will lead onto other projects as soon as I can demonstrate the increased flexibility and cost effectiveness of using Raspberry instead of PLC's in our smaller machines, BUT…... at the end of the day it must be easy to support both on site (world wide) and by our customers own engineers.
@jaroslav_sobota:3ty58xxb:
@Shaun:3ty58xxb:
- Is it possible to connect a K-type thermocouple to the UniPi directly?
No it is not. You need specialized ADC for thermocouples, see e.g. MAX31855 http://www.maximintegrated.com/en/products/analog/sensors-and-sensor-interface/MAX31855.html
OK I understand that K-Type thermocouples cannot easily be used, thank you for answering.
I thought that maybe the 1 wire system would be an option but unfortunatly the temperature range is too low, I need a minimum of +250C.
I do not need a negative temperature value, just from "room temperature" to 250C, do you have any alternative to the 125C standard DS18B20s please?
Hello,
My company is thinking about changing from a PLC control to UniPi to control for one of their smaller bench top machines as a prtotype for future development of an new upgraded product.
I have a couple of questions regarding UniPi before we can start thinking about if Unipi is suitable for this project.
Is it possible to connect a K-type thermocouple to the UniPi directly?
Is it possible to connect a touchscreen directly without using any IO?
if (1) is not possible) Is it possible to connect a “PiFace Rack” to the UniPi board so that a seperate K-type sensor board can be mounted together with the Unipi?
Thanks in advance.
Shaun.
Hello,
My company is thinking about changing from a PLC control to UniPi to control for one of their smaller bench top machines as a prtotype for future development of an new upgraded product.
I have a couple of questions regarding UniPi before we can start thinking about if Unipi is suitable for this project.
Is it possible to connect a K-type thermocouple to the UniPi directly?
Is it possible to connect a touchscreen directly without using any IO?
if (1) is not possible) Is it possible to connect a “PiFace Rack” to the UniPi board so that a seperate K-type sensor board can be mounted together with the Unipi?
Thanks in advance.
Shaun.