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sayahan2003 March 13th, 2018 02:46 PM

High/Low selector
 
My friends,

If in an application we have flow control with pressure override, or pressure control with level override or something like this, how do we know that the selector should be low select or high select? Is this related to the controller action (direct or reverse)? what if one of the controller is reverse and the other one is direct? or both direct?

Thanks

janner_10 March 13th, 2018 04:12 PM

You're gonna have to fix your Google translate or re-phrase that question.

It makes no sense whatsoever.

sayahan2003 March 13th, 2018 04:20 PM

Quote:

Originally Posted by janner_10 (Post 771777)
You're gonna have to fix your Google translate or re-phrase that question.

It makes no sense whatsoever.

you are using the same language for other posts too. If you do not understand, just don't worry about it!

AustralIan March 13th, 2018 04:21 PM

You use logic and common sense every time.

"If loop1 wants to drive the output lower and loop 2 wants to drive the output higher, which one would I rather do?"

boneless March 13th, 2018 04:40 PM

Example from my world.

I want to get a certain temperature (by slowing down flow through a heat exchanger), but I want a minimum flow. Here the highest of the two determines the output.

I want a certain power use on a boiler, but I don't want to exceed my temperature. Here the lowest of the two determines output.

OkiePC March 13th, 2018 04:40 PM

The question makes sense, it is just too generalized to get a good response. Maybe you are looking for general answers. Maybe you have some specific hardware that we can apply the question to...

sayahan2003 March 13th, 2018 05:28 PM

Quote:

Originally Posted by boneless (Post 771785)
Example from my world.

I want to get a certain temperature (by slowing down flow through a heat exchanger), but I want a minimum flow. Here the highest of the two determines the output.

I want a certain power use on a boiler, but I don't want to exceed my temperature. Here the lowest of the two determines output.

Thanks boneless,
Your example are absolutely correct. My question is how you get to the result at the last sentence of each example(lowest or highest).

sayahan2003 March 13th, 2018 05:29 PM

Quote:

Originally Posted by OkiePC (Post 771786)
The question makes sense, it is just too generalized to get a good response. Maybe you are looking for general answers. Maybe you have some specific hardware that we can apply the question to...

Thanks OkiePC,

This is a general question. I don't have a specific hardware.


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