LP/Propane monitoring

[Dbacks2k4]

Anyone have a good recommendation for LP/Propane tank monitoring?

Im going to use a pair of standard 20 lb BBQ tanks with an auto switchover. Would be nice to have a gauge of sorts up in the bus with my other monitoring for water, electrical, etc

I've used the little in-line pressure gauges on my popup and they're OK, but not remote, requires me to go out and look at it. Everything else I'm seeing on Amazon is either a Bluetooth app-based setup or in-tank sensors designed for permanently mounted rv tanks. I want to use BBQ style for ease of swap-out.

Maybe something as simple as a bathroom scale with a remote read-out?

[Tejon7]

I just bought one of those Bluetooth monitors that you mentioned - the Mopeka Pro. The standalone app is ok, but the really neat thing is that it works equally well with the Victron Cerbo GX. The propane % remaining shows up on both my main monitoring screen and on VRM (so I can check tank levels when away from the bus). The Mopeka sensor magnets onto the bottom of any steel tank and can be moved easily between thanks.

If you've drunk the Victron Kool Aid like I have, this might be a good option for you.

[Rucker]

Originally Posted by Dbacks2k4

Anyone have a good recommendation for LP/Propane tank monitoring?
<snip>
Maybe something as simple as a bathroom scale with a remote read-out?

A quick check of options indicates the aforementioned Mopeka wireless monitor is the most likely candidate, if you don't want to go out and touch the tanks.

There's what looks like a crappy digital scale with BT enabled out there, I just don't see how that would work in practical terms if you want the tanks relatively secure underneath.

My tanks are inside the bus in a sealed and vented compartment. Because I don't use the bus full time I don't need to constantly monitor them-I have a hatch on the top of the cabinet to check capacity with a scale-or, like I do now, by just lifting them to check their heft.

[Booyah45828]

That mopeka unit is pretty cool. So long as the sensor doesn't frequently become uncalibrated or fall off. This seems like it'd work similar to a float gauge, but this is remote mounted and non-invasive.

The only other way that I know to check propane levels is by weight, and that'd be pretty hard to do and keep accurate on something that's mobile and bouncing around.

I've seen guys try and use a pressure gauge to tell propane levels, which is a kind of a joke.

[Tejon7]

Originally Posted by Booyah45828

That mopeka unit is pretty cool. So long as the sensor doesn't frequently become uncalibrated or fall off. This seems like it'd work similar to a float gauge, but this is remote mounted and non-invasive.

The only other way that I know to check propane levels is by weight, and that'd be pretty hard to do and keep accurate on something that's mobile and bouncing around.

I've seen guys try and use a pressure gauge to tell propane levels, which is a kind of a joke.

I'm sure excited about it. I tested it briefly on a 20lb tank and it worked as expected. No surprise - that's what it's designed for.

Now I'm going to see if I can get it to work on my main fuel tank. That way, if I'm parked for a long time over winter and using the diesel heater frequently, I'll have an easy way to watch fuel level from my main Victron screen. I don't know what frequency it's little transducer uses, but lpg and diesel aren't so dissimilar that it should matter. There's no way to set up the Mopeka app to use diesel as the measured liquid, but you can change your tank dimensions as needed. I figure that if I find the difference in sound speed between lpg and diesel, then tell the app that my tank is proportionally taller/shorter than reality to compensate for the difference, there's no reason it shouldn't work.

[Booyah45828]

With it calibrated correctly I don't see why it wouldn't measure it. I don't think the frequency will care what fuel you're measuring, so long as it's in a liquid stat. I feel the tank also needs to be a standard rectangular or round tank, as it might not correctly read if you have odd angles in it or a weird shaped tank. Also know that it might never show full on the gauge, because most fuel tanks have a vapor space that takes up to 10 or so percent to the rated capacity. A 50 gallon tank might actually have 55 gallons of volume.

[Dbacks2k4]

Originally Posted by Tejon7

I just bought one of those Bluetooth monitors that you mentioned - the Mopeka Pro. The standalone app is ok, but the really neat thing is that it works equally well with the Victron Cerbo GX. The propane % remaining shows up on both my main monitoring screen and on VRM (so I can check tank levels when away from the bus). The Mopeka sensor magnets onto the bottom of any steel tank and can be moved easily between thanks.

If you've drunk the Victron Kool Aid like I have, this might be a good option for you.

I've not drank the Victron koolaid (almost did, but when Signature Solar EG4 instead) - but I am looking at the Simarine PICO monitoiring system. It has a bluetooth capability, I'll have to investigate if the Mopeka would integrate with that!

Does the sending unit require some sort of battery or a 12v connection?

Thanks!

[Tejon7]

Originally Posted by Booyah45828

With it calibrated correctly I don't see why it wouldn't measure it. I don't think the frequency will care what fuel you're measuring, so long as it's in a liquid stat. I feel the tank also needs to be a standard rectangular or round tank, as it might not correctly read if you have odd angles in it or a weird shaped tank. Also know that it might never show full on the gauge, because most fuel tanks have a vapor space that takes up to 10 or so percent to the rated capacity. A 50 gallon tank might actually have 55 gallons of volume.

Good points. I hadn't considered the vapor space. My fuel tank is a rectangle, so here's hoping it'll work. I'm crawling underneath tomorrow, so I'll try to remember to stick the Mopeka on and start testing.

[Tejon7]

Originally Posted by Dbacks2k4

I've not drank the Victron koolaid (almost did, but when Signature Solar EG4 instead) - but I am looking at the Simarine PICO monitoiring system. It has a bluetooth capability, I'll have to investigate if the Mopeka would integrate with that!

Does the sending unit require some sort of battery or a 12v connection?

Thanks!

As I understand it, a regular 'ol Victron user integrated the Mopeka with their GX device, sent their code back to the Netherlands, and the Victron guys liked it enough to add it to a recent firmware update. If the Simarine pico doesn't currently support these, I bet a clever guy like you could make it happen!

No 12v needed - the integrated battery supposedly lasts 2-3 years and is replaceable. I doubt that longevity, but I've only had mine for two weeks so time will tell...

[Tejon7]

Sorry to further hijack this thread, but I wanted to report back on using the Mopeka sensor for other liquids. It was simpler than I thought to get it to work for my diesel tank. I stuck it to the tank bottom center, drove to the truck stop and filled up, then fiddled with the "tank height" setting in the app until the meter read 100% full. I'm sure it isn't perfect, but good enough for me. Never completely trusted my tiny dash fuel gauge anyway, so another way of measuring puts my mind at ease.

[Rucker]

That is a brilliant idea, putting it on a gas tank. Especially if sometimes the remedy to a broken gas gauge is to drop the tank.

[Tejon7]

Originally Posted by Rucker

That is a brilliant idea, putting it on a gas tank. Especially if sometimes the remedy to a broken gas gauge is to drop the tank.

We're bus converters... Taking something meant for a specific job and bending it to our will is what we do

[Dbacks2k4]

Originally Posted by Tejon7

We're bus converters... Taking something meant for a specific job and bending it to our will is what we do

"can I get an Amen!!" haha