What is a Blind Controller?

Thank you for your valuable reply.

A controler that controls the blinds in an office or house.

This is probably a matter of local terminology. Quite likely it is a controller without feedback. A simple example would be a potentiometer. A more complex example would be sensorless vector control.

Stevie Wonder on the keyboards.

(add funny caption here)

She just cut me off on the freeway exit this morning!

From a controls theory perspective a blind controller can be considered as the input device of an open loop system. Since the OP provides no perspective other than the baffling Instrumentation blog heading, then Stevie Wonder, Dhritarashta, and Louis the Blind can also be plausible answers.

OP, please explain the context of your question.

The guy in Thomas the Tank engine who replaced the other guy who ate more food than he should have.

i was going say a labrador with a special harness, but you can readily get a proper answer if you google "blind controller definition".

Here is you answer.

http://lmgtfy.com/?q=Blind+controller+definition

Glad to help

I'll give it a shot..

A controller normally operates within a feedback or feed-forward loop, which means that each of the measured variables has a desired set-point (value) to be controlled at.

When controlling 'blindly' per the definition you gave, the measured variables' values are displayed at the control panel, but are ignored by the controller (controller is 'blind' to them)

eg. water at a cooling tower is drained/ controlled 'blindly' by having a valve continuously wide-open, without taking the temperature at the cooling tower into consideration, although it is the actual desired temperature set-point which would normally determine the % opening/closing of the valve. All the while the actual temperature is displayed at the control panel, so the Operator can intervene manually if need be (perhaps the cooling pond below the tower may overflow)

If my fictitious example actually exists somewhere, the hole designer probably didn't bother to size the valve properly either, and that is why.

I just rattled that off, but I hope it's self-expalnatory.

Sounds like a control theory definition. (Where have I heard that before.)

You left out any references to a monarch.

Nope, made it up on the spur of the moment...never actually seen a 'blind controller' in 35 years. Monarch ?? Why would I bring Elvis into this....?

I'm still salivating over all that awesome gear you've got on that bench behind you.

What were you saying about 'blind controllers' again please?

There are two kind of Blind controllers. In the picture you will see on the right, the twisty rod type.

On the left you will see the string thingy type.

Both are essential for correct function of the blinds.

You're Welcome.

You must have seen the controllers through a closed blind...neat trick!

Oh god, not another blind-controller voyeur.

My BOSS

sorry... I couldn't resist.

Bill

"Blind controllers are cheap and they work."

That's why the bean-counters love insisting on them over controllers with a good HMI built in.

"They have to be serviced by qualified staff who know how to handle them."

Those personnel are expensive, good luck finding any in the same buildings as the blind controllers are installed in.

It depends upon context. It isn't possible to convey context in a sentence of 5 words: <...What is a blind controller?...>. Please elaborate.

A reply would be appreciated.

It's the guy generally at the start of a processing line that just starts and stops the infeed raw material...at each proceeding step there is a local controller that just maintains his assigned process and must signal the main controller if an emergency shutdown is required...these are generally semi-automation operations where the local controllers are just monitoring the process at their station...

jdbailes is correct. A blind controller does not have a display for the process variable and the control output. There's just a dial for the setpoint. The last time I saw one was back in the 1980's. It dropped out of popularity because you can't see how it's performing. You have to have "blind" confidence that it's doing its job properly.

regards,

Vulcan