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Measuring the Output of a 300 amp Alternator

Discussion in 'Tech How To' started by bubbatrucklover, Jun 22, 2019.

  1. bubbatrucklover

    bubbatrucklover Heavy Metal Red Neck

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    I have a 300 amp alternator, digital battery separator and dual battery setup. After other pressing projects are finished I want to turn my attention to my power distribution/usage.

    I realize I'm not putting out 300 amps ALL the time NOR that I might NEVER see the full 300 amps. PRESUMABLY (IIRC can't find the paperwork and haven't had the time to contact the company) it's a 100 amp idle.

    What I want to do is measure what the alt is ACTUALLY putting out then what each battery is using ( obviously due to the various accessories). I have been leaning towards gauges they use in motor homes. (They will be different then my current brand I LOVE and fwonk with the overall "theme" I have and will have gauge wise but, if placed right won't look bad).

    I have somewhat of an electrical background and I understand that not only is AC/DC an AWESOME fwonkin' rock band :rocker: they are 2 different beasts and I'm having a hard time wrapping my head around the 300 amp alt and gauges LESS then that to measure the usage/output. I think the basic principal applies that if the total draw of all devices from one battery remains LESS then what the meter reads it will be accurate and won't fry it. I also think I'll have to settle on total usage per battery or I would need a ginormous set of gauges blocking the whole windshield. :ohnoes: As for the one to measure the alt at its "fullest" potential I guess I'm being dense/obtuse. :frustration:

    Does anyone have this setup or thoughts of doing it OR how to.

    Thanks in advance. :thumbs:
     
    Last edited: Jun 22, 2019
  2. PenguinLTZ

    PenguinLTZ Administrator Staff Member

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    You can only measure the current that the alternator is putting out, as it is demanded.
    You cannot measure what is going to each battery unless they are mechanically isolated, and you have a CT (current transformer) on each line from the isolator.
     
  3. bubbatrucklover

    bubbatrucklover Heavy Metal Red Neck

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    Well Penguin this is the isolator I have : https://www.amazon.com/ProMariner-ProIsoCharge-Battery-Isolator-250Amp/dp/B004VBGU4E

    I realize it's 250 amp but, that was what my alt was before I had them test it then since they had it I had them bump up the amps "just because" and kept the 250 amp fuse in line from the alt. Not sure when/if I'm swapping out the isolator and truthfully didn't think of the 50 amp difference when I had them beef up the alt. That isolator isn't a cheap throw away. :frustration:

    These are the monitoring gauges I was eyeballing:

    https://www.amazon.com/gp/product/B013PKYILS/ref=ox_sc_saved_title_1?smid=A1T3LOAKNUUM9N&psc=1

    I don't know if the above is in line of what you are talking about or not. This is further down the honey do list on my truck and not top priority. (truthfully I don't have enough accessories added to warrant a second battery AND my current aux battery is fwonked and needs replacing) I just like doing research and project planning way in advance.

    Thanks for the input. :thumbs:
     
  4. bubbatrucklover

    bubbatrucklover Heavy Metal Red Neck

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    SLIGHT change in my info. It turns out I ONLY have a 250 amp alt. (and had upgraded from a 200 amp alt.) and I had planned accordingly with the matched isolator. :thumbs:

    OCCASIONALLY I make the right choices the FIRST time when planning things out. :rocker:

    :naughty:
     
  5. EppNation

    EppNation I'm NEW... What now?

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    I had nearly identical 'wants' as far as monitoring my electrical production and consumption but slightly different setup. I have dual AD244 alternators and dual batteries (6.5TD). I bought some of those el cheapo digital display gauges on amazon to try 'em out. These linked and any other one like it is meant to be a gauge for measuring off of an appliance/load/something that consumes. What I was trying to do deemed the alternator the 'source' and the battery the load, which simply doesn't work with what's provided in the kit. After much research, it was going to be more involved than I was willing to commit to at the time. The project still remains benched.

    I did however find a very reasonably priced multimeter that was capable of measuring DC amps in high quantity. This I did get and use all the time. TBH, this multimeter satisfied my desire to measure my electrical production and consumption. Although it's not as convenient as a glance at a gauge, it tells me what I need to know to verify everything is working properly. I added utilizing this multimeter to my oil change ritual to check amps being produced by each alternator and the draw being pulled from each battery with a simple clamp over each respective +12v wire.

    AIMO MS2108A Auto Range Digital Clamp Meter 400 AC DC Current Hz Tester
     
  6. EppNation

    EppNation I'm NEW... What now?

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    How would you go about doing this? In some kind of way with a clean display that can operate in-cabin full time.
     
  7. PenguinLTZ

    PenguinLTZ Administrator Staff Member

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    in dash amp gauges have been in use for years
     

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