Weird electrical problem

Discussion in 'Boatbuilding' started by mariobrothers88, Sep 5, 2021.

  1. mariobrothers88
    Joined: Sep 2020
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    Location: San Diego, CA

    mariobrothers88 Senior Member

    Hi guys im testing out the 24v seawater pro watermaker system and im having this weird problem. I connect the wires for the high pressure pump to the 100 amp breaker which is then directly connected to the 24v 100ah lithium battery just like the instructions say. However when i connect the cable directly to the battery the high pressure pump immediately starts running even through the breaker is off! When I flip the breaker on, there is a spark and the battery breaker shuts off and the pump stops working. I figure i must have wired the breaker incorrectly so i change the wiring to the breaker and the exact same thing happens! I figure i must have a defective breaker so i buy a different 100amp breaker, but the exact same thing happens!! When the breaker is off, everything works fine and i can make water without any issues.

    For the life of me i can't figure out what the problem can be. I triple checked all the wires and all positives is connected to positives and all negatives connected to negatives. Any idea what the problem can be?

    Thanks in advance guys!!!
     
  2. Ike
    Joined: Apr 2006
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    Location: Washington

    Ike Senior Member

    My first reaction is the same as yours, defective breaker. We need photos of the wiring, the breaker and a circuit diagram.
     
  3. fallguy
    Joined: Dec 2016
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    Location: usa

    fallguy Senior Member

    You only wire the watermaker breaker on the hot wire. Or all breakers.

    I think you are wiring the breaker in parallel to the watermaker. Then it automatically trips the battery breaker. But the watermaker would work if the breaker is open.
     
  4. Zilver
    Joined: Nov 2007
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    Location: Amterdam the Netherlands

    Zilver Junior Member

    I think fallguy is right ? If you switched it parallel to the pump,it creates a short cut (spark !). It should be wired something like :

    BATTERY plus - MAIN FUSE - BREAKER - plus pump -PUMP - negative pump - BATTERY negative

    Hans

    PS If you really wired it parallel you should be careful with working on the rest of your electric installation ; without the main fuse you might have created a fire or melting battery.
     
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  5. fallguy
    Joined: Dec 2016
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    fallguy Senior Member

    It should be wired as follows;

    Battery negative to negative bus. Watermaker negative to negative bus.

    Battery hot to battery breaker or fuse within 7" of battery. Battery hot to bus or distribution panel. Positive line to watermaker breakered or fused within 7" of bus or source. Positive fused or breakered line to watermaker positive wire.

    It is a rookie mistake; do it once and you won't ever again.

    Remember you are fusing to protect the positive wires from burning, not protecting the watermaker. This is the concept that drives fuse or breaker sizing. A watermaker pump requires big wires, generally. The amp draw of the device and distance from source is what drives wire sizing.

    Zilver's comment is important. Do not skip the main battery fuse or breaker. It trips for wiring errors in setting up.
     
  6. mariobrothers88
    Joined: Sep 2020
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    Location: San Diego, CA

    mariobrothers88 Senior Member

    Hi guys thank you so much for your replies! So I wired the positive battery to the breaker and then the breaker to the positive terminal of the pump. I then wired the negative terminal of the pump to the negative terminal of the lithium battery.

    When I hook it up like this the pump starts running even though the breaker is off! When I flip the breaker on, it still continues to run without any problems. So I figure the breaker must be defective so I replaced the breaker, and still have the same problem! So weird!! But this is the correct way to wire it right?

    I don't have a bus right now since this is just for testing.
     
  7. fallguy
    Joined: Dec 2016
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    fallguy Senior Member

    You need to tell us what breaker.
     
  8. Ike
    Joined: Apr 2006
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    Location: Washington

    Ike Senior Member

    I still think it's the breaker. What kind of breaker are you using? DC breakers are usually only in the positive side. They are more like a switch. AC breakers are wired to both sides. If you are using an AC breaker you're doing it wrong. As said above it should be wired in series, not parallel. And it should be the only load on the circuit.
     
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  9. gonzo
    Joined: Aug 2002
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    Location: Milwaukee, WI

    gonzo Senior Member

    It is really simple to test the breaker. You can either use a continuity tester, or disconnect the wire from it and see what happens.
     
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  10. mariobrothers88
    Joined: Sep 2020
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    Location: San Diego, CA

    mariobrothers88 Senior Member

    I'm using the breaker that came with the seawater pro kit so it should be the correct one I'll post a picture of it once I get better internet, thanks for all the help and advice guys I truly appreciate it!!! You guys are absolutely amazing!!
     

  11. Zilver
    Joined: Nov 2007
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    Location: Amterdam the Netherlands

    Zilver Junior Member

    Is the "breaker" a switch ? If so you might have broken both breakers in your earlier setup, and "welded" them in permanent ON-state.

    I looked on the internet at the seawater pro website, and they're not very clear about connections - ac vs. dc setups - wiring etc.
     
    Last edited: Sep 12, 2021
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