86turbodsl
Active Member
That's exactly it. My new tank gage has a little black cover over the center of the indicator you pull off to press on the remote transducer. It reads "remote ready".
Large LP Gas Tank Fuel Monitor via Transducer
- Thread starter BraveSirRobbin
- Start date
That's exactly it. My new tank gage has a little black cover over the center of the indicator you pull off to press on the remote transducer. It reads "remote ready".
BraveSirRobbin
Moderator
I would love more details on this method as it seems to be a desired option for me.
Do you have model numbers, pics, etc...? I wonder if I can get a "direct" replacement for one already mounted. If not, I am guessing it would be a PITA to add to a tank?
Thanks for any input.
BSR
BraveSirRobbin
Moderator
I found THIS pdf file on an "off the shelf" package that I'm going to further investigate. Further details on the remote ready gauge specifics can be found in THIS pdf file.
This is what I eventually want. A voltage output proportional to the fuel level inside the tank via an "off the shelf" product.
Edit: Squibb Taylor also has some solutions towards the end of THIS pdf file.
This is what I eventually want. A voltage output proportional to the fuel level inside the tank via an "off the shelf" product.
Edit: Squibb Taylor also has some solutions towards the end of THIS pdf file.
BraveSirRobbin
Moderator
Hi Anthony;
I'm not sure I'm fully getting what you are doing. Am I correct in assuming you have a hall effect sensor that is "mimicking" the manual gauge reading?
If so, are you then applying a voltage to that sensor and getting out a variable voltage as you move the float sensor? Can you see the manual gauge dial while you are doing this test?
If the answers are yes to the above questions you should be able to formulate a response graph. What I would do is this:
Measure the output voltage with a multimeter while you run through the range of the float sensor. Hopefully you can read the mechanical dial while doing this (would make it easier). Do this in precise increments so what you would end up with is a listing of say 1/8, 1/4, 3/8, 1/2, etc... mechanical dial readings with their corresponding output voltages.
Now plot the readings (mechanical reading vs output voltage) and graph the results. Hopefully you get something close to a straight line (which would represent a linear output).
Now, just follow the steps in my Analog to Digital Converters guide to establish an equation which would represent fuel level.
AnthonyZ
Active Member
So it's hard to explain with words. The existing meter is round. The needle spins within it like a speedometer. If you remove the meter from the tank, underneath you'll find it's just flat brass. There is no physical connection to the moving portion of the float gauge located within the tank. Instead, the float inside the tank turns a magnet underneath the flat brass in a circular pattern. That, in turn, spins the needle in the outer meter via a second magnet that's physically attached to the bottom of the needle. The problem with using the hall effect sensor is that it can detect the magnet but, it doesn't differentiate between the direction of the needle's spin (as in CW or CCW). It just outputs a signal based on the magnetic field's strength. I can measure that out put AND watch the existing needle ('cause I just glued the hall effect sensors on top of the the round meter, at the edge). If I place the sensor near the needle's full position, the signal is essentially the same as it would be if the needle were pointed at the empty position. Because it's round, the full and empty needle positions are right next to each other. If I place the hall effect sensor in, say, the midpoint of the meter, I get the strongest signal at that point but if the tank is nearing empty or nearing full, I get diminished signal with no way to read if the needle is in front of or behind the hall effect sensor. So, I'm using two sensors on each meter and I just need to spend some time working out the best logic to correct for it. It's not too big a deal. I just need to get back up there next week to approach it again.
Sandpiper
Active Member
Nice explanation.....and nice idea.
I think I got it except for the flat brass part.....
On the logic to separate the low level from the high level.......I have one idea for you to consider. The logic would have to make some assumptions, based on recent past readings, so it would also have to keep a history of readings. But you could do this:
1. If the level is moving slowly, then it is being consumed and is decreasing, moving toward the low level end.
2. If the level is moving fast, the tank is being refilled, and the reading is moving toward the hi level end.
These are the only two cases. It seems like it should work.
Thanks for posting. This is an interesting idea.
By the way.....I have much industrial experience in installing electrical equipment in electrically classified areas. For a tank such as this, according to NFPA 497, Figure 5.9.2b, a 15' diameter spherically shaped Division 2 volume would defined around the tank refill connector and any vents such as a relief valve. There is no Division 1 volume defined. With Division 2, there are other methods of meeting the area classification besides using intrinsic safety methods- such as being hermetically sealed.
Not seeing what the difference is between what the commercially available Robertshaw sensor / wireless transmitter and what AnthonyZ is trying to create (reinvent?)
The sensor exists in a commercially acceptable package (I am sure including all the safety / certification issues that are appropriate).
What is left is how to "hack" into the sensor's wires and convert that to serial data. A bit of ee and calculations.
The sensor exists in a commercially acceptable package (I am sure including all the safety / certification issues that are appropriate).
What is left is how to "hack" into the sensor's wires and convert that to serial data. A bit of ee and calculations.
86turbodsl
Active Member
Go here: http://www.propane101.com/floatgauge.htm My tank gage face is the bottom center one of the 4 dials shown on the page. If you zoom into that photo, you can see it reads "remote ready" you pull the little black cap off and put on your transducer. It reads rotation of the dial needle. That's it. I had to drain the tank to install the gage.
AnthonyZ
Active Member
Proof of concept on the "Remote ReadY" gauge is proven. I went back to my project this past week and placed hall effect sensors on the face, under where the black filler cap is and used a screwdriver to turn the dial for testing. One sensor will easily and accurately track the dial. So I now have two tanks of three being measured as often as every five seconds and the resolution is great. Works like a charm and was relatively easy to calibrate.
In my case, the build is kind of complex but, it's rather elegant. I built a solar panel charging station that tops off a 12v7ah battery at the remote tank location. The power circuit is used to drive the the hall effect sensors (about $3/ea.), which are tied to analog inputs on a MaxSerial Arduino (about $15). The Arduino does all the calculations and then sends ASCII strings wirelessly to a second Arduino at the house via Xbee modules (Pro, maybe $100 for the two Xbee's and the two Xbee shields). The second, or receiver, Arduino is serially connected to an HAI panel that uses messages to display the tank levels and WebLinkII software to email the client when the tanks are low. At the head end, I plan on using an Avocation Systems SR2 serial router to allow the serial data to also be fed to a Convergent Living 15" touch screen in the kitchen which I can use to display a graphical depiction of the individual tank levels.
Now we're getting somewhere...
In my case, the build is kind of complex but, it's rather elegant. I built a solar panel charging station that tops off a 12v7ah battery at the remote tank location. The power circuit is used to drive the the hall effect sensors (about $3/ea.), which are tied to analog inputs on a MaxSerial Arduino (about $15). The Arduino does all the calculations and then sends ASCII strings wirelessly to a second Arduino at the house via Xbee modules (Pro, maybe $100 for the two Xbee's and the two Xbee shields). The second, or receiver, Arduino is serially connected to an HAI panel that uses messages to display the tank levels and WebLinkII software to email the client when the tanks are low. At the head end, I plan on using an Avocation Systems SR2 serial router to allow the serial data to also be fed to a Convergent Living 15" touch screen in the kitchen which I can use to display a graphical depiction of the individual tank levels.
Now we're getting somewhere...
My LPG provider (FerrellGas) offers a service called "SmartFill". The gauge on the tank looks like the one 86turbodsl has. The wire goes to a transmitter that is literally stuck on the tank with glue or tape (it's a gray thing about four inches tall, kinda pyramid shaped but not exactly, all covered in opaque plastic so you can't see what's inside). I have a receiver in my home that displays the tank level (0-100%). It has a phone connection. Once a day, it calls Ferrell to give them the current tank level. When it hits about 25%, they show up and fill it within a couple of days. The receiver can actually handle two tanks. This tank was installed a few years ago, and is a rental tank, i.e., owned by Ferrell.
Last summer, I had a standby genset for my home installed about 150 feet from my home. My existing tank is about 250 feet from the genset and is only a 250 gallon tank. Since the genset uses a little over two gallons an hour at 50% load, I decided to get a dedicated 500 gallon tank for it so I could go a week or so of continuous genset usage without needing to refill. Unfortunately, Ferrell won't lease tanks that are dedicated to home standby generators (they don't need filling very often since the only extended outages are during/after a hurricane), so I had to buy it. They were supposed to fit it with the SmartFill transmitter but they forgot. The installer said it was no problem putting it on later, although I never had it done.
If it was possible to purchase this solution and get access to the codes, it seems like it would be a great solution for a HA system.
Last summer, I had a standby genset for my home installed about 150 feet from my home. My existing tank is about 250 feet from the genset and is only a 250 gallon tank. Since the genset uses a little over two gallons an hour at 50% load, I decided to get a dedicated 500 gallon tank for it so I could go a week or so of continuous genset usage without needing to refill. Unfortunately, Ferrell won't lease tanks that are dedicated to home standby generators (they don't need filling very often since the only extended outages are during/after a hurricane), so I had to buy it. They were supposed to fit it with the SmartFill transmitter but they forgot. The installer said it was no problem putting it on later, although I never had it done.
If it was possible to purchase this solution and get access to the codes, it seems like it would be a great solution for a HA system.
A propane level sensor I just found. Looks like this company has several types of propane (and other liquid) sensors. Found it while trying to find the OE replacement fuel sensor for my boat.
http://www.rochestergauges.com/Pages/PDFs/TS012.pdf
http://www.rochestergauges.com/Pages/PDFs/TS012.pdf
BraveSirRobbin
Moderator
That looks like a newer version of the one I posted earlier in this thread (post 33). I should have updated this thread with some pics of the install, so here they are. The tape holding the gauge was temporary as an adapter mount had to be made for that specific tank (out of the three tanks, all the mounts were slightly different. Only one let the gauge sit in and use the remaining screws from the old gauge).
Attachments
apostolakisl
Senior Member
This appears to be the "out of the box" solution that others are building. But, where to buy? I can't seem to find it for sale anywhere.
apostolakisl
Senior Member
What abou this one? I can't figure out from the description if it is the standard magnetic driven guage that we have on our tanks. The price is nice at about $18.
http://angliaautogas.com/catalog/index.php...;products_id=22
http://angliaautogas.com/catalog/index.php...;products_id=22
