Control Level of corn in Grain Bin

Discussion in 'The Projects Forum' started by mcwells, Jan 8, 2011.

  1. mcwells

    Thread Starter New Member

    Jan 8, 2011
    5
    0
    Please excuse me Im sure this is a very trivial question. I want to run my bin auger (1/2hp 120v ac motor when the biomass pellett gets to the bottom of the bin ans shut it off when the pellet gets to the to of the bin. Thanks so much for the help. I attached a diagram.
    Mark
    [​IMG][​IMG]
     
    Last edited: Jan 8, 2011
  2. bertus

    Administrator

    Apr 5, 2008
    15,648
    2,347
    Hello,

    The image is to large in the PDF, some text is cut off.

    Bertus
     
  3. mcwells

    Thread Starter New Member

    Jan 8, 2011
    5
    0
    Sorry I revised it to be able to read
     
  4. bertus

    Administrator

    Apr 5, 2008
    15,648
    2,347
    Hello,

    What kind of level switches are used?
    Are the level switched free when the level goes down again?

    Do you need a kind of start / stop system?
    Start the feeder when the level is low and stop the feeder when the level is high.

    Is the output separately controlled?

    Bertus
     
    mcwells likes this.
  5. Kermit2

    AAC Fanatic!

    Feb 5, 2010
    3,792
    948
    A simple method would be to wire the bottom switch to turn the motor on, and put the top switch in the wire from the bottom switch to the motor. If done this way, the motor would start running everytime the top switch was uncovered and would keep the bin constantly 'topped off'.

    Adding a third switch somewhere in the middle would be needed to keep the motor off until the level is lower AND it could make this a 'no electronic component' solution. Meaning relay and switches only.
     
    mcwells likes this.
  6. thatoneguy

    AAC Fanatic!

    Feb 19, 2009
    6,357
    718
    Having been near one when it went off, will there be grain dust in the air that adds the requirement of "arc free"/low voltage control?

    Fuel Air Explosions can ruin your day. (The fuel being dust from the grain)
     
    mcwells likes this.
  7. mcwells

    Thread Starter New Member

    Jan 8, 2011
    5
    0
    Thanks for the replies! As for the dust low voltage control, since the bin I want to regulate is a 55 gallon drum I don't think it will have too much dust. With that said an arc free low voltage solution would be better. Kermit's explanation makes much sense to me so I will ponder what that wire diagram would look like. I really appreciate the help guys!

    As for your question Bertus I do want a start stop system to turn the auger on, fill up the drum and turn it off when full. There are several bin level switches out there but I was thinking about a mercury tilt switch that would move when the corn or biomass pellet level moved. The auger is a 2.5in by 12' and wont be here until probably Monday. Next weekend I need to be moving corn. The boiler I use is outside and has its own control system. The boiler will be pulling (by auger) out of the drum below the low level. I thought about using its control system but it runs a 1RPM motor to feed the burn pot. This bigger auger will probably run once a day to feed the 55gal drum
     
  8. thatoneguy

    AAC Fanatic!

    Feb 19, 2009
    6,357
    718
    If it is a 55 gallon drum, a sharp IR Rangefinder unit in the lid/top would work. A lot of circuits are around using them for maintaining the salt levels in their water softening systems.

    It is a bit more complicated, but you don't need to go full microcontroller with it. The upside is that it is non-contact, and wouldn't involve any switches that could stick/clog/etc.
     
    mcwells likes this.
  9. John P

    AAC Fanatic!

    Oct 14, 2008
    1,634
    224
    I'd have thought that what you want is a system with a relay that turns on when the level falls below the lower switch, and turns off when the level rises above the higher switch. That's easy enough to achieve if the relay has a second contact that keeps it turned on once the lower switch has triggered it; this second contact is in series with the upper switch. The switches have to be ON when the biomass level is below them, and OFF when it's above them.

    So basically the relay coil is in series with a circuit that has two parallel branches, either of which can power the coil. The first branch is the lower switch alone, and the second branch is the upper switch in series with a normally-open contact on the relay itself.
     
    mcwells likes this.
  10. beenthere

    Retired Moderator

    Apr 20, 2004
    15,815
    282
    As this is to fill a hopper for a pellet stove, you really only need to sense low level. The auger is going to move the corn at a pretty constant rate, so arranging it to run for long enough to fill the hopper past the 3/4 mark might be a less costly solution.
     
    mcwells likes this.
  11. Bill B

    Active Member

    Nov 29, 2009
    61
    0
    I saw a guy do something similar for his Capstone project. He used a PLC to control the motors. Proly a bit too expensive for what you wanna do but its a thought.
     
  12. thatoneguy

    AAC Fanatic!

    Feb 19, 2009
    6,357
    718
    Autofill for Water (brewing). Change your switches and the output would be a relay instead of a solenoid, but it would fit what you are describing with simple circuits.

    This sonar module has both digital outputs for a microcontroller (PIC, AVR, Ardunio, BASIC Stamp, etc), as well as a 10mV per inch output that could be interfaced with a non-uC circuit. Place sonar at top of drum, pointing down, contact-free solution.

    The IR Rangefinder is similar to the sonar solution, but does need a bit more supporting electronics to get a 10mV/inch output.
     
  13. mcwells

    Thread Starter New Member

    Jan 8, 2011
    5
    0
    I have wracked my brain and come up with this as a simple solution. What do you think?

    Thanks in advance!!!
     
  14. mcwells

    Thread Starter New Member

    Jan 8, 2011
    5
    0
    I will post pics when I am done! Thanks for the help
     
Loading...