Ultrasonic water level sensor ?

[Jaws]

Given the propensity Autotrails have for giving totally random and far from accurate reading for water levels, has any one fitted / used / had experience of using an ultrasonic level sensor on a motorhome tank ?

 

[rosalan]

I do not think that any single marque, let alone Autotrails have a copyright on inaccurate readings of fluid levels but a really accurate reading would be an interesting novelty. I am guessing it could prove to be more expensive than the present 5 level indicator.
p.s. My grey waste can sometimes show half full with the tap open.

 

[Ridgeway]

Would one of the Mopeka type devices that are designed for LPG work ?

 

[Jaws]

Would one of the Mopeka type devices that are designed for LPG work ?

It might do..
So far all I have managed to find use a transponder that goes in the top of the tank..
The Mopeka type would be ideal if it did work, but £50 down the drain if it did not !

 

[mitzimad]

Dip stick fool proof

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[fat haggis]

Would one of the Mopeka type devices that are designed for LPG work ?

Its held by magnetic force. A bit hard for a water tank

 

[mitzimad]

actually thinking about this the best thing would be a sight tube like an oil tank

 

[Two on Tour]

It might do..
So far all I have managed to find use a transponder that goes in the top of the tank..
The Mopeka type would be ideal if it did work, but £50 down the drain if it did not !

No a Mopeka will not be suitable for measuring the water level in a tank, how do I know, I tried it.

 

[Jaws]

No a Mopeka will not be suitable for measuring the water level in a tank, how do I know, I tried it.

Of course, that has now got me wondering why !
Thibk I might ring them on Monday ... see if I can talk to a techy bod

 

[Two on Tour]

Of course, that has now got me wondering why !
Thibk I might ring them on Monday ... see if I can talk to a techy bod

I'll save you a phone call John.
I spoke with Chris at Mopeka in the States when I wanted to use a Mopeka sensor to measure the diesel in my night heater tank.
The Mopeka sensor is calibrated for the density of propane and it measures the height of the liquid propane by sensing the point at which the density changes as the ultrasonic waves hit the air above the liquid propane. Propane has a density of 493 kg/m3 and water has a density of 997 kg/m3, so you can see that propane is nearly half the density of water.
Diesel has a density of about 880 kg/m3 and I managed to get the Mopeka to sort of read diesel by playing with the tank height settings in the app and had a little more success when I started running my night heater on home heating oil at a density nearer 800 kg/m3, but it still took fiddling with the app setting to get some sort of reading and correlation between the fuel level and a readout on the app.

I have the Mopeka sensor up for sale in the classified at the present, but if you want to play with it and to put your mind at rest, then you are welcome to borrow it to experiment with.

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[PeteH]

Dip stick fool proof

That`s not nice! The poor O/P was only asking a question..

On the serious side. Ultrasonic devices have to be calibrated for the material being investigated. eg. my ultrasonic thickness meter was calibrated for mild steel. Gave all sorts of weird reading if used on (say) aluminium!. BTW, it had to be recalibrated and re-certified periodically too.

 

[Jaws]

I have the Mopeka sensor up for sale in the classified at the present, but if you want to play with it and to put your mind at rest, then you are welcome to borrow it to experiment with.

Nahhh.. Appreciate the offer Paul but happy to take your word for it mate !

 

[nicholsong]

If I want to double-check the water guage readings I unscrew the lid in the MH floor and gaze or dip in.

Geoff

 

[Ditcha]

Wouldn't you think the likes of mopeka would make devices for measuring different media, missing a trick there me thinks.

 

[Gellyneck]

I think Dane Diabalo fitted replacement sensors to his AT and believe they're much more accurate than the "standard" fit. Can't remember the name of them though.

Jaws
Just found the thread\s John,

Grey Water Tank Wierdness

Hi folks, have an 2019 Autotrail Delaware HB. I’ve noticed a couple of weeks ago that the grey tank was emptying very slowly, and flushed it from the drain with a hose. Seemed to fix it. Now it seems the full tank sensor alerts even when I know there is little in the tank, and draining starts...

www.motorhomefun.co.uk

Water-level meter (fresh water tank) not working

Two days ago we filled our 100-liter fresh-water tank then noticed yesterday that the reading is still "full", even though the tank is in fact just under half-full. This morning we put in more water (not full); still the reading is "full". This is of course inconvenient and needs to be put...

www.motorhomefun.co.uk

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[Tony50]

On my Chausson we can see the level of water in the tank through the filling hatch in daylight, level meter in instrument is useless.

 

[Flook]

Ultrasonics works in different ways depending on the application. Having come from an electronics background which included some ultrasonics when I was a young man.

I suppose you could have a transponder of sorts that sent out an ultrasonic wave when operated, this wave would pass through water as if it was not there to a certain degree. Now if a float was placed into the water with a metal insert, and the transponder adjusted or calibrated for the signal wave to rebound off the metal where the ultrasonic wave was monitored by a receiver built into the transponder, this could by the electronics be converted in a measured form to tell you the accurate water level you have in any motorhome tank of fresh or water water.

I am sure there must be something out there that does this, as ultrasonics is not new, and is used for all types and kind of measurements, including testing of grass pipe seals before placing underground and filled in, it is also used for under water sea bed tests etc. So what your asking I would have thought would be easy peasy for those experts to put together.

Jaws, I hope this may go somewhere near to what you were asking.

Flook

 

[SIFTA SAM]

How much time will be spent suitably leveling the motorhome up first before being able to obtain these accurate water reading?

 

[two]

I had a Euromobil that displayed the water tank contents as a %. It dropped in tens (90, 80, ..) until 10%, then dropped in 1% increments. I don't know how accurate it was but it was more than good enough and the tank was pretty empty by the time the gauge was displaying single digits. Don't know how it worked because it never required investigation.
Now, we have a rough idea how long a tank will last and the pump starts to remind us if we forget.

 

[Soozywoozy]

Would love to know also.. we have a massive 180 litre water tank and our gauge is divided into quarters, which means when its a quarter full its somewhere between. 44 litres and zero!

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[two]

If you are nervous about your gauge's accuracy, I suggest you calibrate it first:
Empty it then add 10litre at a time with your watering can (you do have one, don't you?).
Take a note of the number of litres added to reach each of the levels indicated.
You will probably find that it's not linear, for all sorts of reasons, but you will at least know what each of the readings means in terms of the amount remaining.
I'd expect the measurements to be fairly repeatable, at least for the season.

 

[Gromett]

I looked at using ultrasonics myself. The problem was all the ones I could find wouldn't survive submersion. In a moving van this would happen. I gave up on the plan.

 

[the1andonly]

The level system on my rapido is pointless. The overflow also comes out of the lid onto floor before the overflow pipe.
I added 2 float switches and leds to indicate max level when filling and a low leval at 2 showers worth left. Being level helps, if too far out the float sticks.
I once read a diy project that used a non contact capacitane method with an arduino it used a cpper tape on the outside of the container. It was demonstrated with a 2l bottle, vastly different aspect ratio to my water tank ie long and not vry tall.

 

[Jaws]

Ultrasonics works in different ways depending on the application. Having come from an electronics background which included some ultrasonics when I was a young man.

I suppose you could have a transponder of sorts that sent out an ultrasonic wave when operated, this wave would pass through water as if it was not there to a certain degree. Now if a float was placed into the water with a metal insert, and the transponder adjusted or calibrated for the signal wave to rebound off the metal where the ultrasonic wave was monitored by a receiver built into the transponder, this could by the electronics be converted in a measured form to tell you the accurate water level you have in any motorhome tank of fresh or water water.

I am sure there must be something out there that does this, as ultrasonics is not new, and is used for all types and kind of measurements, including testing of grass pipe seals before placing underground and filled in, it is also used for under water sea bed tests etc. So what your asking I would have thought would be easy peasy for those experts to put together.

Jaws, I hope this may go somewhere near to what you were asking.

Flook

Yesssss.. as there does not seem to be a commercial priced answer in my price range this is what i was thinking
As ultra sonics is going to be difficult I will investigate putting to use 3 miniature klystrons I have in the loft that are happy in the K band
Using microwave coupled with a suitable receiver ( only has to be a detector and RF amp, an I F amp anda low power af amp which you can get in one module nowaday for very little ) use that set up to drive an LM3914 with a few LEDs on its output..
Happy to work with RF but not boned up on sonic gear

Gonna have to dig out those Klystrons now !and hope they are civvy ones and not military which are more often 48 v and a pain in the bum !

 

[Jaws]

I looked at using ultrasonics myself. The problem was all the ones I could find wouldn't survive submersion. In a moving van this would happen. I gave up on the plan.

I was more thinking of shooting through the side of the tank as I canna get inside it anyway!

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[Chuns]

I fitted a Mopeka to my water tank, and it works a treat. Yes, a bit dear, but It comforts me to know what is there fairly accurately and consistently, rather than see that I have a half full tank, which then might read a quarter full after drawing a small kettle of water, as it is with the installed system. Which is it?

It is easy to fit and wire in if you have even the most basic DiY skills. As my water pump is mounted in the tank area so I was able to piggy-back onto its +ve and -ve.

 

[Two on Tour]

I fitted a Mopeka to my water tank, and it works a treat. Yes, a bit dear, but It comforts me to know what is there fairly accurately and consistently, rather than see that I have a half full tank, which then might read a quarter full after drawing a small kettle of water, as it is with the installed system. Which is it?

It is easy to fit and wire in if you have even the most basic DiY skills. As my water pump is mounted in the tank area so I was able to piggy-back onto its +ve and -ve.

Are you sure it's a Mopeka you have fitted as they are battery powered by a 3 volt cell not 12 volts ?

 

[Diabalo]

It drove me crackers as I like things to work, so I replaced mine with Horst miracle probes, been ok ever since. Got them sent over from the states half the price than over here.

 

[rosalan]

I am sure there is a good reason not to use it but years ago my cars used to have a floating ball-cock device in the petrol tank. When moving it was all over the place but when parked it was fairly accurate at measuring how much fuel was in the tank.

 

[Jaws]

I fitted a Mopeka to my water tank, and it works a treat. Yes, a bit dear, but It comforts me to know what is there fairly accurately and consistently, rather than see that I have a half full tank, which then might read a quarter full after drawing a small kettle of water, as it is with the installed system. Which is it?

It is easy to fit and wire in if you have even the most basic DiY skills. As my water pump is mounted in the tank area so I was able to piggy-back onto its +ve and -ve.

Any chance of a picture and or more details of which Mopeka product you used chuns ?

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