Temperature control circuit design

Thread Starter

BENCASEY83

Joined Jan 27, 2017
45
Hi guys

I have been given a project in work which involves changing the process of two identical oil storage tanks. The current setup on both tanks is just a simple start stop control through a contactor for a 3 phase motor which is turning on and off a small mixer paddle. The temperature is controlled by a simple PT100 temperature probe and a setpoint controller which switches in and out when temp is low and then switches off when the temp is reached. Which is all fine.

What they want now is to have the temperature control the same but now on a Friday they want the temperature to drop down to 50 degrees on Friday when the plant closes and then have the temperature rise to 60 degrees at around 5am on Monday morning automatically so it will be ready to use when the shift begins at 7am.

I have been looking at different temperature controllers as the one i have is just a simple on/off controller and will not be capable of doing this. In particular i was looking at West controllers which have dual inputs/outputs and countdown timers events/ etc as i have one in operation on another piece of equipment in the plant. And I was also looking at 7 day timers etc. I will attach links of things below but i am looking for some guidance/ input to possible ways of what would be the best way to go about this as i am also thinking of a PLC as well because they are saying they may well want to install VFDS further down the line for speed control, so whatever i do now I want to future proof it for easy add ons. Each tank has its own panel and controls so i want to do the same controls on each panel so essentially something not too over complicated.

I know the message is a bit long winded but thanks in advance guys.


Temp controllers: https://ie.rs-online.com/web/c/auto...4877807&sort-by=P_breakPrice1&sort-order=desc


Time clocks : https://ie.rs-online.com/web/c/auto...-time-switches/?applied-dimensions=4291870457
 

Reloadron

Joined Jan 15, 2015
6,128
What you want is a temperature controller which includes a RTC (Real Time Clock). A decent home programmable temperature controller but you want one which will take the input from the existing sensor. I see no need to get overly fancy with the control since what you now have seems to be basic On/Off control. You only need a single loop. I remember using West Temp Controllers but that was years ago. You can try finding a dual set point controller, I have some old ones made by Honeywell. Then tie in a RTC so the set point changes for weekends.

Ron
 

Thread Starter

BENCASEY83

Joined Jan 27, 2017
45
What you want is a temperature controller which includes a RTC (Real Time Clock). A decent home programmable temperature controller but you want one which will take the input from the existing sensor. I see no need to get overly fancy with the control since what you now have seems to be basic On/Off control. You only need a single loop. I remember using West Temp Controllers but that was years ago. You can try finding a dual set point controller, I have some old ones made by Honeywell. Then tie in a RTC so the set point changes for weekends.

Ron
Hi Ron

Thanks for the input. No pun intended lol. I have been looking at this controller below for what you suggested and I think it will work unless you see any different

What you want is a temperature controller which includes a RTC (Real Time Clock). A decent home programmable temperature controller but you want one which will take the input from the existing sensor. I see no need to get overly fancy with the control since what you now have seems to be basic On/Off control. You only need a single loop. I remember using West Temp Controllers but that was years ago. You can try finding a dual set point controller, I have some old ones made by Honeywell. Then tie in a RTC so the set point changes for weekends.

Ron
What you want is a temperature controller which includes a RTC (Real Time Clock). A decent home programmable temperature controller but you want one which will take the input from the existing sensor. I see no need to get overly fancy with the control since what you now have seems to be basic On/Off control. You only need a single loop. I remember using West Temp Controllers but that was years ago. You can try finding a dual set point controller, I have some old ones made by Honeywell. Then tie in a RTC so the set point changes for weekends.

Ron
Hi Ron
Thanks for the input. I have been looking at this controller with the link below from what you suggested I think it will work. Also I have a West EC 44 on another piece of kit in the plant and it works as you described as well but the delivery time on these is too long and I Need to start this project tomorrow. I have attached a link at the very bottom for the West controller for comparison.

https://ie.rs-online.com/mobile/p/pid-temperature-controllers/8947014/
What you want is a temperature controller which includes a RTC (Real Time Clock). A decent home programmable temperature controller but you want one which will take the input from the existing sensor. I see no need to get overly fancy with the control since what you now have seems to be basic On/Off control. You only need a single loop. I remember using West Temp Controllers but that was years ago. You can try finding a dual set point controller, I have some old ones made by Honeywell. Then tie in a RTC so the set point changes for weekends.

Ron

Hi Ron

Thank you for the input. I have used a west controller myself in the past for a more or less identical process some years back i have attached the link below of which one i used and i think i could use again but the problem is that the delivery on these is too long as i have to start the project tomorrow. I have attached another link at the bottom from Radionics of one of the controllers i think will do the same job, unless you see something different that i dont.



West controller: https://www.west-cs.com/products/models/dual-temperature-controller-pro-ec44/



Link to controller i think i could use: https://ie.rs-online.com/web/p/pid-temperature-controllers/8947014/
 
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