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I'm looking for flow sensor for petroleum products — Parallax Forums

I'm looking for flow sensor for petroleum products

There is an astonishing selection of petroleum compatible flow sensors - from sketchy inexpensive items to $1K+. Is there a middle ground that someone has knowledge of? I'm trying to measure fuel consumption, diesel in particular, of about 1-3 gallons per hour. This is a 10KW generator head belt driven by a Yanmar L100 ~9HP single cylinder diesel engine. This is a one-off fabrication for home power in case of storm - I live in south Florida. Very tired of gasoline generators and the attendant gasoline supply issue when things blow down. I can always get plenty of diesel (even when things get blown away) and it stores much better than even non-ethanol gasoline not to mention the better efficiency of diesel engines. I'm hoping someone has a suggestion for such a sensor or at least a source or two to search on. Control panel is, of course, Prop driven so looking to add an extra input.

Comments

  • evanhevanh Posts: 15,091
    Isn't the geeky thing to do is drop down some solar PV panels and use a fancy inverter/charger with batteries. And while you're at it, go off-grid.

  • I am used to measuring high flows of petroleum products and know that low flows are very difficult to measure accurately.
    Some google research indicates diesel engine consumption meters are expensive and difficult to calibrate.
    If the installation is stationary and secure, I would consider mounting the diesel tank on mass sensor(s) and measuring the change in mass. Of course you would need flexible fuel lines to increase the sensitivity.
  • Try using an automotive impeller flow meter you can buy at automotive supply or speed shops, and calibrate it for diesel. They use an LED interrupter to count revolutions and/or pulses. Second, use a calibrated "fill" tank (a pint or so), something like a float bowl carburetor but larger. The tank fills up quickly and then a timer counts until the next fill, calibrate from there.
  • evanh wrote: »
    Isn't the geeky thing to do is drop down some solar PV panels and use a fancy inverter/charger with batteries. And while you're at it, go off-grid.
    I would very much like to do both - solar for prime power with old fashioned fossil fuel power generation for coverage when solar's not enough. Off the grid? In Florida? Nope. Our benevolently dictatorial utility companies have greased the proper folks such that lack of an active power connect to power utility means you lose your CO (Certificate of Occupancy) and Planning and Zoning people get very, very upset with that not to mention the mortgage holder and insurance provider. Of course if you have an active connection but don't actually use any power there's a base rate fee for the connection you don't want and don't use.
  • macrobeak wrote: »
    I am used to measuring high flows of petroleum products and know that low flows are very difficult to measure accurately.
    Some google research indicates diesel engine consumption meters are expensive and difficult to calibrate.
    If the installation is stationary and secure, I would consider mounting the diesel tank on mass sensor(s) and measuring the change in mass. Of course you would need flexible fuel lines to increase the sensitivity.

    That is an interesting approach that would work very well as I do have a remote (by a couple of feet) fuel tank. Hmm...
  • PropGuy2 wrote: »
    Try using an automotive impeller flow meter you can buy at automotive supply or speed shops, and calibrate it for diesel. They use an LED interrupter to count revolutions and/or pulses.
    that's not a bad idea and definitely worth experimenting with. I'll report on my progress.
    Second, use a calibrated "fill" tank (a pint or so), something like a float bowl carburetor but larger. The tank fills up quickly and then a timer counts until the next fill, calibrate from there.
    Ah yes, the day tank mechanism. I have a bit of experience with that concept with much larger generation and marine propulsion systems and it's a great concept but realistically trouble prone. I still break out in a sweat recalling repriming the fuel rail on a very large marine diesel in 8' seas in a 140F engine room with 12" clearance on all sides. This was secondary to a blown fuse on the day tank makeup pump. I have plenty of anecdotes involving day tank setups, none good.
  • Seconding the weight sensor idea. Since it's a liquid tank you don't even need a sensor under each leg; you can use hinges on one side and sensors only on the other, or even a single sensor in the middle. Good sensors are expensive but there are some surprisingly cheap ones on eBay that would be OK for a personal non-legal system. A HX711 works great for reading them. (Disclaimer: I work for a company that sells actual industrial weighing equipment.)
  • localroger wrote:
    ...you can use hinges on one side and sensors only on the other...
    I'd be wary of such an arrangement. Any non-sensor, such as a hinge, that supports any of the weight is going to skew the results. OTOH, if you can compute the leverage accurately, you can correct for it.

    -Phil
  • You can use a diesel fuel flowmeter, these are on Ebay for $12-$30. I use turbine flow meters when precision flow is required such as Flow technolgy, Cox, Flow dynamics etc.. The turbine meters read pulses per gallon. With a signal conditoner you can convert the signal to square wave and read it with the Prop or Bs2.. You just need to use the calibration K-factor.
  • Phil, ratio systems are very common in some industries; they are for example used in almost all water plants to weigh the chlorine remaining in treatment tanks, which is a rather important function. Hinges turn out not to be a very bad source of errors compared to balance, binding, and other issues. (Long experience here.) For a personal project to make sure the genny isn't going to die in the middle of the night, it won't be a problem.

    I wouldn't use a flow meter for this at all, because small errors integrate to big ones.
  • How about the usually used swimmer in the tank like in almost any car?

    Mike
  • I would go with a flow meter for diesel. A mass/ weight sensor could be damaged or shifted in the event of the very occurrence the OP is concerned about. Enter the volume added then each turn of the flow meter is so much stuff out with a non-volatile storage in case power gets interupted.
  • My Keurig coffeemaker has a captive float in the bottom of its water reservoir. It's held to within two inches of the bottom and simply returns an empty/not_empty signal to the embedded micro via a break-beam optical sensor. You could do something similar. Just confine a float so that its highest allowed position is where the fuel level becomes critical, and put a sensor there. When the fuel level goes below that level, the float will no longer be sensed.

    -Phil
  • evanhevanh Posts: 15,091
    pmrobert wrote: »
    Off the grid? In Florida? Nope. Our benevolently dictatorial utility companies have greased the proper folks such that lack of an active power connect to power utility means you lose your CO (Certificate of Occupancy) and Planning and Zoning people get very, very upset with that not to mention the mortgage holder and insurance provider. Of course if you have an active connection but don't actually use any power there's a base rate fee for the connection you don't want and don't use.
    Wow! That's pure corrupt.

  • Same here in California,

    OK I can use PG&E as a Battery for my Solar System. When I produce more as I use it goes into the Grid, when I need more then I get it back.

    At the end of the year there is a 'True Out' where I have to pay what I used more. (@0.24 cents) and I MAY qualify to get money back for electricity I produced more (@0.11 cents), but - hmm - MAY.

    And sure, even while I produce more then I need I have some base costs to pay ($14/month).

    Same goes for Water/Sewer even with a own Well and own Septic tank I still have to pay $102/month for - hmm - base cost of water and sewer?

    And the best part is - If PG&E shuts down electricity I am NOT allowed to use my Solar System.

    Funny, isn't it?

    Mike
  • Welcome to the people's republic of California
  • pmrobertpmrobert Posts: 669
    edited 2020-06-19 23:43
    I'm very grateful for all the input given in this thread. So many ideas, all with pros and cons. I have two goals, neither of which is essential. #1 is reporting fuel level in main tank which is a 33 gallon poly marine tank which is located on the slab underneath the genset baseplate which the engine and generator head occupy. #2 is quantifying burn rate vs power demand. In the past 40 years I've used gasoline gensets. They're not very efficient whatsoever and gas is difficult to come by when entire counties are without power for up to 3 weeks in some areas. Gas doesn't store well at all especially since the advent of the addition of ethanol - stored gas is trash in about 6 weeks in our high humidity warm environment. I've switched to an over engineered belt driven diesel solution with a brushless generator head this year for several reasons (lower fuel burn, much easier availability of inexpensive agricultural non-highway diesel fuel, engine does not depend on electricity at all to run, etc....). I'm instrumenting current and voltage per leg, frequency, oil temp, air filter DP and so forth. I have my own well and water treatment system so if I have power I'm good to go for essentials. Yes, Florida is strife with corrupt lobbyist driven legislation, crooked politicians of all stripes and overall idiocy but it is manageable for this native who knows where to avoid such wierdness. Florida Man does exist I assure you! Thank you and keep ideas coming should they pop into your head.
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