Communication for new device?

Hi

Firstly I am new to control and have more of an IT background so if my questions seem fundamental or are on the wrong track please excuse me.

I am involved with the development of a new sensor that will be used in industrial environments. We are at the stage where we are deciding how to communicate with this device that will ulimately be used for control purposes.

I have a few questions that I would answers to or some direction on the types of things we should consider.

  1. Should such a device communicate via modbus or are their other alternatives that should be considered?
  2. Modubs RTU or TCP/IP?
  3. How are modbus devices communicated with before they are programmed with a modbus address (eg. is there a standard for programming the modbus ID on such devices or is it device specific)?
  4. Are there other considerations in relation to communication we should be investigating?

I'm sure I will have are other questions that will come to mind or in response to any answers but would appreciate any assistance or help with the direction I should be looking.

Regards ilr

Reply to
ilr
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Factors like the type of industry you're targeting will influence the best solution:

a) If you target the process industries, you might want to consider a Fieldbus Foundation

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interface.

b) For other industries it might be worthwhile to consider other fieldbusses like Profibus.

c) A simple 4 - 20 mA interface would easily connect you to any PLC or DCS.

d) I d> Hi

Reply to
pieter steenekamp

Thank You Pieter

I really appreciate you advice

a,b) At this stage the device is for use in wineries. I will have a look at fieldbus and profibus to see what they offer.

c) 4-20mA was considered but other information is required from the sensor other than just the analogue output as well as a requirement to store calibration information. Are their devices that can be used to control from an output such as modubs/fieldbus or profibus rather than using PC hardware to control?

d) Ultimately their will be multiple devices throughout the winery for measurement and control.

Regards ilr

Reply to
ilr

For the application you have described, I would suggest you look seriously at Profibus

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- specifically Profibus DP.

If you don't want to use PC hardware, Siemens (Vipa and others) sell small footprint PLCs that can communicate using Profibus and control other analog and digital devices at the same time. This equipment is already in common use in wineries and breweries world-wide and likely some of your clients already use it.

Good luck.

Cameron:-)

Reply to
Cameron Dorrough

A typical winery probably already has a PLC and you just want to interface to existing PLCs.

If you want to go the fieldbus route, there is probably general bias towards Profibus and Foundation Fieldbus (FF) in Europe and US respectively.

I know many people will disagree with me, but if all other factors are ignored, and you consider just the pure technical specs, then FF is in my view better than Profibus. But then, Profibus will probably not only meet, but exceed the minimum requirements, so other factors could influence the best choice in your specific case. If I were you I would ask a couple of your potential customers what brand PLC they use and then contact those PLC manufacturers for their preferred or recommended interfacing standard.

Pieter

Camer> > Thank You Pieter

Reply to
pieter steenekamp

Thanks to both of you for your assistance.

Sorry for my ignorance but could you clear something up for me.

I know that PLC's in general take an analogue or digital signal (on/off) from some kind of sensor or device and then do something based on that signal. Is it common for PLC's to also take a signal from sensors or devices that talk modbus, fieldbus, profibus etc. and do something based on that value eg PID control (the signal is neither analogue or digital but a numerical value)? Does the PLC act as a "master" device polling the sensor at regular intervals or the other way around. Are these kind of PLC's common or am I on the wrong track?

Thanks in advance

Reply to
ilr

Thanks to both of you for your assistance.

Sorry for my ignorance but could you clear something up for me.

I know that PLC's in general take an analogue or digital signal (on/off) from some kind of sensor or device and then do something based on that signal. Is it common for PLC's to also take a signal from sensors or devices that talk modbus, fieldbus, profibus etc. and do something based on that value eg PID control (the signal is neither analogue or digital but a numerical value)? Does the PLC act as a "master" device polling the sensor at regular intervals or the other way around. Are these kind of PLC's common or am I on the wrong track?

Thanks in advance

Reply to
ilr

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