Page 1 of 2 12 LastLast
Results 1 to 30 of 33

Thread: Lipo Load Bank for Discarging (moved from swap shop)

  1. #1
    Join Date
    Apr 2007
    Location
    MI
    Posts
    3,112

    Default Lipo Load Bank for Discarging (moved from swap shop)

    I wanted to bring this back to the top. I am looking to build one of these.

    I would be willing to build 2 at the same time if someone was interested. Since Tyler posted his prices have gone up and parts alone one would cost $250 not including shipping. Is anyone interested? If not I will only buy enough parts for myself.

    2 of these resistors: http://www.alliedele...k1r0e/70022401/
    1 of these heat sinks: http://www.alliedele...06000/70115158/
    Thermal grease if you don't already have it: http://www.alliedele...-150g/70125596/
    2 of these fans: http://www.alliedele...624hh/70104890/

    Thanks
    Mike

  2. #2
    Join Date
    Apr 2007
    Location
    ON
    Posts
    9,384

    Default

    Links don't work for me but, may work for others.
    Nortavlag Bulc

  3. #3
    Join Date
    Apr 2007
    Location
    ON
    Posts
    9,384

    Default

    I was maybe thinking of building one since I have everything except the resistors. What is the price at alliedele for resistors?
    Nortavlag Bulc

  4. #4
    Join Date
    Apr 2007
    Location
    MI
    Posts
    3,112

  5. #5
    Join Date
    Mar 2010
    Location
    ME
    Posts
    3,438

    Default

    So what would the total cost be, just wondering... I find it a huge pia to discharge my larger packs, no super quick way to do it... and often I bite off more then I can chew when I charge more lipos for the day then I end up using...

  6. #6
    Join Date
    Apr 2007
    Location
    MI
    Posts
    3,112

    Default

    After sleeping on it, I am going to retract my offer. There really isn't any benefit buying parts for one assembly or two. However, I fixed the links below. The total cost is just a hair under $250 (shipping NOT included). Thanks again to Tyler, I am simply regurgitating the info he provided directly to me.

    2 of these resistors: http://www.alliedelec.com/ohmite-tap600k1r0e/70022401/
    1 of these heat sinks: http://www.alliedelec.com/aavid-ther...6000/70115158/
    Thermal grease if you don't already have it: http://www.alliedelec.com/mg-chemica...150g/70125596/
    2 of these fans: http://www.alliedelec.com/ebm-papst-624hh/70104890/

  7. #7
    Join Date
    Apr 2007
    Location
    ON
    Posts
    2,908

    Default

    I use a set of 8 of these in series for my 2S and 4S packs.
    6 of these in series would be good for 6S packs.

    http://ca-en.alliedelec.com/arcol-hs50-2r5-f/70596828/

    I forgot to say, you can also use these to cook on.

    Larry
    Last edited by TRUCKPULL; 01-21-2016 at 12:15 PM.
    Past NAMBA- P Mono -1 Mile Race Record holder
    Past NAMBA- P Sport -1 Mile Race Record holder
    Bump & Grind Racing Props -We Like Em Smooth & Wet

  8. #8
    Join Date
    Sep 2007
    Location
    NC
    Posts
    2,778

    Default

    Anytime Mike,

    I also want to stress I would not recommend using these unattended. The loads banks will draw about 22A@35V when wired in series and 45A@20V when wired in parallel. It only takes several minutes to fully dump a 5000mAh battery and it's very easy to walk away and forget.

    I recommend using these through a charger capable of controlling the discharge like an iCharger Duo. This will safely monitor voltage and temp of the discharging battery.

    If you do use it as a standalone discharger, please invest in a simple cell checker with low voltage buzzer.

    Tyler

    IMG_2118.jpg
    IMG_0853.jpg
    Tyler Garrard
    NAMBA 639/IMPBA 20525
    T-Hydro @ 142.94mph former WR

  9. #9
    Join Date
    Apr 2007
    Location
    MI
    Posts
    3,112

    Default

    Well, I finally got mine assembled and started "fiddling" around with it last night. Should be a pretty good tool, but still have lots to learn. Thanks again to Tyler to helping me along the way!
    Attached Images Attached Images

  10. #10
    Join Date
    Apr 2007
    Location
    WA
    Posts
    8,335

    Default

    Mike, I just finished mine up as well (THANKS TYLER!!)...

    Even came up with a way to add some rubber feet to it. I can thread in 1/4-20 Furniture posts/feet into these rubber inserts, if desired. And I added a pair of 4mm taps, in case I decide (probably won't) to run the fans off the load, rather than the power supply, or for plugging in a voltage monitor of some kind.

    Is that the iCharger S/W you have there on your laptop??

    Mine is setup in parallel, since I don't generally use anything over a 4S pack, and my 6S setups use two 3S packs.

    20160227_172554.jpg

    20160228_110053.jpg

    20160227_162800.jpg

    20160227_162842.jpg
    Darin E. Jordan - Renton, WA
    "Self-proclaimed skill-less leader in the hobby."

  11. #11
    Join Date
    Apr 2007
    Location
    WA
    Posts
    8,335

    Default

    Quote Originally Posted by longballlumber View Post
    The total cost is just a hair under $250 (shipping NOT included). Thanks again to Tyler, I am simply regurgitating the info he provided directly to me.

    2 of these resistors: http://www.alliedelec.com/ohmite-tap600k1r0e/70022401/
    1 of these heat sinks: http://www.alliedelec.com/aavid-ther...6000/70115158/
    Thermal grease if you don't already have it: http://www.alliedelec.com/mg-chemica...150g/70125596/
    2 of these fans: http://www.alliedelec.com/ebm-papst-624hh/70104890/
    I think the prices must have gone up... My parts cost $317.00 shipped, and I probably have another $80+ in wire, contacts, etc. A lot, I know, but sometimes, you just have to pay to play the game, and this will have enormous benefits for Time-Trials and heat racing, as well as general battery management.
    Darin E. Jordan - Renton, WA
    "Self-proclaimed skill-less leader in the hobby."

  12. #12
    Join Date
    Apr 2007
    Location
    MI
    Posts
    3,112

    Default

    Quote Originally Posted by Darin Jordan View Post
    Mike, I just finished mine up as well (THANKS TYLER!!)...

    Even came up with a way to add some rubber feet to it. I can thread in 1/4-20 Furniture posts/feet into these rubber inserts, if desired. And I added a pair of 4mm taps, in case I decide (probably won't) to run the fans off the load, rather than the power supply, or for plugging in a voltage monitor of some kind.

    Is that the iCharger S/W you have there on your laptop??

    Mine is setup in parallel, since I don't generally use anything over a 4S pack, and my 6S setups use two 3S packs.
    The Feet are a good idea. Mine was already sliding around on my work surface. The third fan is probably a good idea too. I was discharging a 6S pack last night and that aluminum heat sink got up to 185F! I need to make different jumpers for parallel too. Although I do have some 6S packs I will be using 4S mostly.

    The software on the laptop is LogView. I don't know much about it, but it seems to be a freeware/shareware type tool. I think they Hyperion's use the same software. Just another thing for me to learn.

    http://www.logview.info/forum/index.php?pages/home/

    Later,
    Ball

  13. #13
    Join Date
    Apr 2007
    Location
    WA
    Posts
    8,335

    Default

    Thanks, Mike!
    Darin E. Jordan - Renton, WA
    "Self-proclaimed skill-less leader in the hobby."

  14. #14
    Join Date
    Apr 2007
    Location
    ON
    Posts
    9,384

    Default

    185F, whoa! Those are huge heat sinks. What about fans on the other side to speed up air flow?
    Nortavlag Bulc

  15. #15
    Join Date
    Apr 2007
    Location
    MI
    Posts
    3,112

    Default

    Quote Originally Posted by ray schrauwen View Post
    185F, whoa! Those are huge heat sinks. What about fans on the other side to speed up air flow?
    When you think about it; it's ALOT of energy that is being turned into heat in only a few mins. I don't suspect you will get the actual "peak" temp down, but more fans would minimize how long that "peak" is sustained. Once the load ramps down the 2 fans cool everything very quickly.

  16. #16
    Join Date
    Apr 2007
    Location
    WA
    Posts
    8,335

    Default

    Quote Originally Posted by longballlumber View Post
    When you think about it; it's ALOT of energy that is being turned into heat in only a few mins. I don't suspect you will get the actual "peak" temp down, but more fans would minimize how long that "peak" is sustained. Once the load ramps down the 2 fans cool everything very quickly.
    Tyler also recommends that you run the fans off the power supply, not off the "load" (I think I saw that you already were). That way the fans run at full speed and beyond the discharge cycle.

    My fans are 24V, though they work fine on 12V too. I just finished up a new power supply that uses a pair of 75A power supplies and has 12V and 24V taps.

    One of these days, maybe I'll add some LEDs and other "bling"... :)
    Last edited by Darin Jordan; 03-02-2016 at 02:20 PM.
    Darin E. Jordan - Renton, WA
    "Self-proclaimed skill-less leader in the hobby."

  17. #17
    Join Date
    Sep 2007
    Location
    NC
    Posts
    2,778

    Default

    Darin are you missing a 0 in your wattage? 150W isn't much for cycling.
    TG
    Tyler Garrard
    NAMBA 639/IMPBA 20525
    T-Hydro @ 142.94mph former WR

  18. #18
    Join Date
    Apr 2007
    Location
    WA
    Posts
    8,335

    Default

    Quote Originally Posted by RaceMechaniX View Post
    Darin are you missing a 0 in your wattage? 150W isn't much for cycling.
    TG
    I meant to type "75A"... Oops. :)
    Darin E. Jordan - Renton, WA
    "Self-proclaimed skill-less leader in the hobby."

  19. #19
    Join Date
    Sep 2007
    Location
    NC
    Posts
    2,778

    Default

    That's more like it!
    Tyler Garrard
    NAMBA 639/IMPBA 20525
    T-Hydro @ 142.94mph former WR

  20. #20
    Join Date
    Feb 2008
    Location
    GB
    Posts
    2,726

    Default

    I could be being naive here as I am inexperienced with electronics, but I was thinking of peltier devices, 60w devices are pretty cheap, a stack of 10x12v devices for 2-3s and 20x24v ones for 4-6s would be about £50/$75 for the lot.

    If they were stacked together would the cold side of one would cool the hot side of the next etc, so you would only need to sink away 60w of heat from the end of each stack?
    Paul Upton-Taylor, Greased Weasel Racing.

  21. #21
    Join Date
    Apr 2007
    Location
    ON
    Posts
    9,384

    Default

    The one hot end of the stack I think would go nuclear. I have one somewhere...
    Nortavlag Bulc

  22. #22
    Join Date
    Sep 2007
    Location
    NC
    Posts
    2,778

    Default

    Hey guys if you are looking at building a load bank now is a good time. I just check on Allied Electrics site and some of the 1 and 2 Ohm planar resistors are back in stock and reduced prices.

    https://www.alliedelec.com/spectrol-...00jb/70218911/

    https://www.alliedelec.com/ohmite-tap600k2r0e/70022403/

    -Tyler
    Tyler Garrard
    NAMBA 639/IMPBA 20525
    T-Hydro @ 142.94mph former WR

  23. #23
    Join Date
    Apr 2007
    Location
    ON
    Posts
    2,908

    Default

    Tyler, Mike, or Darin

    The for-mentioned heat sink - https://www.alliedelec.com/aavid-the...6000/70115158/
    is not in stock.
    They recommend this as a replacement - https://www.alliedelec.com/aavid-the...6000/71076834/
    $71.00 US seems a little pricey.
    About how much were the ones that are not in stock at the moment, if you can remember??

    Larry
    Past NAMBA- P Mono -1 Mile Race Record holder
    Past NAMBA- P Sport -1 Mile Race Record holder
    Bump & Grind Racing Props -We Like Em Smooth & Wet

  24. #24
    Join Date
    Sep 2007
    Location
    NC
    Posts
    2,778

    Default

    From memory they were about the same price. Go onto eBay and find a suitable replacement.
    https://www.ebay.com/itm/No-15J9645-...QAAOSwhpZaBfYk

    https://www.ebay.com/itm/Brand-New-N...cAAOSwAC1aBb8d
    Tyler Garrard
    NAMBA 639/IMPBA 20525
    T-Hydro @ 142.94mph former WR

  25. #25
    Join Date
    Feb 2008
    Location
    GB
    Posts
    2,726

    Default

    I want to be able to graph discharges at close to the 45A I run my boats at to test packs, as well as drain unused packs back to storage voltage quickly.

    The Powerful FMA chargers have good graphing capabilities, and resistive discharge capabilities, but to get the maximum discharge out of one you would need a different resistor for each voltage of battery you use, which would be 5 for me.

    The high end duo ichargers can use the voltage booster that they use to charge big packs to increase the voltage of the discharge up to a user definable level (under their max charge voltage) so on a 4010 duo I could set it to 42V and with a single 1ohm resistor I can discharge a single cell through to a 6s pack (the biggest I use) at 40A. Unfortunately however the ichargers don't have the graphing ability FMA do, so I have been waiting for one of them to combine both of the features, but I see above that there is a third party graphing software for the icharger, how are you guys getting on with that? I guess it has had some use now, can it log amps volts and was over milliamphours?

    Now getting onto topic, while I have been searching this I saw that the flyby have come up with a pretty neat solution to the resistive load, which is rewiring an 1800-2000w hairdryer, they are available everywhere from as little as £20 ($25?), small and light so field usable, and never get hot enough on the outside or exhaust to burn you, it is likely to be a fair bit louder than a resistor on a big heatsink with multiple slower fans, but could also do duty as a boat drier for the unfortunate, and a LiPo warmer when fed with lower voltages.
    https://www.rcgroups.com/forums/show...discharge-load
    Paul Upton-Taylor, Greased Weasel Racing.

  26. #26
    Join Date
    Sep 2007
    Location
    NC
    Posts
    2,778

    Default

    Paul,

    To answer your questions:

    Graphing: The iChargers do have the capability of logging data and graphing using LogView. It's free and works quite well. I cycle batteries on my 4010 and use the logging feature to save both charging and discharge cycles in one file. The software is very good. Only downside is it does not log the cell IR values. I have to manually record these.

    Discharging: The Junsi has two limits. 40A or 1000W, which ever comes first. The key is to match the load resistance to the battery voltage you are trying to drain. As you say the Junsi has a buck boost converter inside which can increase the voltage to the load to reduce the current in till it hits the 1000W limit. You also need a load resistor that is capable of 1000W too.
    I use a 0.5 Ohm or 1 Ohm load with mine. The 0.5Ohm is for 4 cells and below and the 1 Ohm is up to 10 cells. This way the charger can always hit the 40A limit on the battery side without hitting the 40A limit on the load side.

    Tyler
    Tyler Garrard
    NAMBA 639/IMPBA 20525
    T-Hydro @ 142.94mph former WR

  27. #27
    Join Date
    Aug 2007
    Location
    TX
    Posts
    368

    Default

    Have you tried testing battery packs at realistic rates of discharge using the West Mountain Radio CBA 10X Multiplier? That would seem to be the perfect instrument for what y’all are wanting to do.

  28. #28
    Join Date
    Sep 2007
    Location
    NC
    Posts
    2,778

    Default

    I am not going to that high of a level since I can compare the lower current testing to what actually happens in a boat. If a chemistry does well on the cycle I run it generally will work well in the boat. What I run into is the mechanical limitation of the battery tabs and wires at the high currents. I do have a friend who is pulse testing these cells in the several hundreds of amps range. The results seem to correlate well.
    Tyler Garrard
    NAMBA 639/IMPBA 20525
    T-Hydro @ 142.94mph former WR

  29. #29
    Join Date
    Apr 2007
    Location
    ON
    Posts
    9,384

    Default

    Some people have gone as simple as using a plastic storage bin with unraveled magnet wire submerged in water to create resistive loads. Some even use this method to test server power supplies to make sure the can be loaded to full capacity.
    Nortavlag Bulc

  30. #30
    Join Date
    Dec 2010
    Location
    NY
    Posts
    3,115

    Default

    I bought 4 of these on ebay for $22 each if someone wants 2 LMK https://www.ebay.com/itm/VISHAY-RESI...72.m2749.l2649

Page 1 of 2 12 LastLast

Bookmarks

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •