"DEF low, but you know it's not" problem

ACZL wrote:
Sadly, it's not problems w/ any of the big 3's engines. Rather the DEF system is going to be the Achilles heel going forward. Semis are no different. Can thank our tree huggers for this.

This comment is what got me thinking on this...

Am a technologist and generally speaking...design stuff and part of
that is to solve problems along the way to get to whatever marketing
is telling engineering departments they want to sell...

All light sources has some UV content and dependent on the materials
those designers employed...phosphorous is the main material that
has the source light waves strike to glow and produce white light
More will convert more to white light and the evenness of the coating
dictates how much UV might escape

Some UV does get through and is up to the designers' specification

Think tannin booth lights...lots and lots of UV

Now the controls side...

If optical, how did they do it?

Am most familiar with a side mounted sensor at the 'minimum' level
they wish to tell the computer...but with comments of 'full' and
non-linear gauge readings...tells me either a couple side optical
(more $$$) or one that shines up/down to reflect off of the surface

Tough, as the water line/surface is NOT always smooth, but with
waves & disturbances from the road surface

Hysteresis is how that would be muted a bit and fits comments of
how slow the gauge readings are


If floats, then that too need hysteresis as it will rock up and
down from the waves/disturbance

But floats do sink. Partially to all the way...


If optical...is it on constantly? or do they pulse it on some
time cycle?


Noodling this some more...most likely a float...optical is too
expensive and maintenance issue if the liquid has a coating/clouding/etc
portion of their life cycle to coat the lens...why spark ignition
never got going...the lens/window clouds up...

PS...also thank the tree huggers for removing 'some' the 'brown'
from the sky...

I've had asthma since a kid and my last trip to see my grandson
in S Cal...had several attacks due to the higher levels of SMOG
down there...so I do appreciate what the Tree Huggers have done

Just look up 'smog', 'images' and 'china' and/or 'India" and you
might remember what many urban areas in NA looked like in the 60's
and 70's

In China...the government stopped all traffic into the capital
'cuz of smog. Some were stuck there for up to 4 days...the gov
also banded private vehicles in the city during the Olympics
so that the foreigners would NOT see the typical smog...