peetee22
Posts: 2
Joined: Tue Oct 12, 2021 8:51 pm

Work project

Tue Oct 12, 2021 9:08 pm

Hi, I'm new to the Pi world.
I'm really sorry if this is in the wrong area or something.

I want to try and control 2 x pumps (through relays) and a solenoid valve by reading water pressure from a 4-20mA transducer. Then adding some outputs for high and low pressure alarms and high and low tank level sensors. Also, have a touchscreen display with real time pressure reading/info and be able to change settings for pumps, valve and alarms.

Would this be possible on a Raspberry Pi?
Would I need additional I/O boards?
Is there a code that would be best/easiest for this type of control?

Thank you

pcmanbob
Posts: 11802
Joined: Fri May 31, 2013 9:28 pm
Location: Mansfield UK

Re: Work project

Thu Oct 14, 2021 3:01 pm

Hi.

So yes you will need additional I/O boards,

One for the relays ,

probably one to read the pressure from a 4-20mA transducer,

Depending on what you want to drive from the output for pressure alarms you may well need some interfacing circuits.

Yes it should be possible using a pi, I would suggest python if you want to code your own GUI on the display.

With any project like this break it down in to smaller chunks and get each bit working first especially the hardware.
We want information… information… information........................no information no help
The use of crystal balls & mind reading are not supported

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thagrol
Posts: 5839
Joined: Fri Jan 13, 2012 4:41 pm
Location: Darkest Somerset, UK
Contact: Website

Re: Work project

Thu Oct 14, 2021 5:17 pm

As you're asking about this for a "Work project" I have two questions for you:

1. How much are you paying for the help?

2. Given you're talking about valve control, pressure monitoring, and alarms you're probably talking about a process and/or safety critical system. Are you sure it's wise to DIY this?
I'm a volunteer. Take me for granted or abuse my support and I will walk away

All advice given is based on my experience. it worked for me, it may not work for you.
Need help? https://github.com/thagrol/Guides

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B.Goode
Posts: 13022
Joined: Mon Sep 01, 2014 4:03 pm
Location: UK

Re: Work project

Thu Oct 14, 2021 5:27 pm

peetee22 wrote:
Tue Oct 12, 2021 9:08 pm
Hi, I'm new to the Pi world.
I'm really sorry if this is in the wrong area or something.

I want to try and control 2 x pumps (through relays) and a solenoid valve by reading water pressure from a 4-20mA transducer. Then adding some outputs for high and low pressure alarms and high and low tank level sensors. Also, have a touchscreen display with real time pressure reading/info and be able to change settings for pumps, valve and alarms.

Would this be possible on a Raspberry Pi?
Would I need additional I/O boards?
Is there a code that would be best/easiest for this type of control?

Thank you

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peetee22
Posts: 2
Joined: Tue Oct 12, 2021 8:51 pm

Re: Work project

Thu Oct 14, 2021 11:08 pm

thagrol wrote:
Thu Oct 14, 2021 5:17 pm
As you're asking about this for a "Work project" I have two questions for you:

1. How much are you paying for the help?

2. Given you're talking about valve control, pressure monitoring, and alarms you're probably talking about a process and/or safety critical system. Are you sure it's wise to DIY this?
Yes it is for a piece of equipment that my company buy from other manufacturers. But as they are quite expensive controls, I wanted to try to build a one off/test unit using a Pi as the controller. I'm doing it off my own back and if it doesn't work then I'll just use the hardware for myself on little projects around the home.

Obviously I can't pay for the help. I don't mind teaching myself. I just wanted to know if it was viable or if it would be a waste of my time and money.

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thagrol
Posts: 5839
Joined: Fri Jan 13, 2012 4:41 pm
Location: Darkest Somerset, UK
Contact: Website

Re: Work project

Fri Oct 15, 2021 1:41 am

peetee22 wrote:
Thu Oct 14, 2021 11:08 pm
Yes it is for a piece of equipment that my company buy from other manufacturers. But as they are quite expensive controls, I wanted to try to build a one off/test unit using a Pi as the controller. I'm doing it off my own back and if it doesn't work then I'll just use the hardware for myself on little projects around the home.

Obviously I can't pay for the help. I don't mind teaching myself. I just wanted to know if it was viable or if it would be a waste of my time and money.
Obviously, it's your decision. If you own the business, I understand. If you're an employee, why are you willing to work for free and fund it yourself? Your time and skills have value, as does that of others.

As for whether it's viable, I can't say. Technically feasable? Probably. Viable in terms of time and money? No idea. Viable in terms of safety, performance, reliability, standards compliance, and legality? Again, I can't say. But those are some of the factors in driving up the price of the units that are currently being purchased.

I've said my piece so I'll be leaving this topic now rather than accidentally start an argument.
I'm a volunteer. Take me for granted or abuse my support and I will walk away

All advice given is based on my experience. it worked for me, it may not work for you.
Need help? https://github.com/thagrol/Guides

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