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platypus avatar image
platypus asked

Should I connect my loads to the MPPT charge controller directly? (MPPT 100 | 20)

I have a system with a ~20-25amp load.


I noticed in the manual that loads were connected via the LOAD terminals

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The maxiumum amperage that the MPPT has is 20amps. Thus it doesn't scale well with my system. The manual showed a different approach, where you can have your DC loads connected straight to the battery.

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I noticed that the battery protect's POS cable connects directly to the POS LOAD terminal.


❓Other than the amperage difference, is there any benefit to connecting to the LOAD terminals rather than directly to the battery? Why did the manual choose to use both in the above example (POS smart shunt to the MPPT rather than the battery itself).


I am also using a battery protect, so i'll have no need of the the features that prevent overcharging in the MPPT unit.

MPPT Controllers
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wkirby avatar image
wkirby answered ·

The manual show both examples as different ways to connect loads, both examples are correct and it is then up to the system designer to choose an appropriate one for their system. Of course these are examples and further adaptations can be made to suit the requirements.

The first example has the advantage of the MPPT being able to measure the current out of the LOAD terminals

For your needs, the second example is better because your load current is more than 20A, as you have already mentioned.
You can see that the red wire going from the positive load terminal to the Battery protect is a thin line. This suggests that it is a control signal to control the Battery Protect from the MPPT if you want to. If you don't want to control the Battery Protect from the MPPT then don't connect this wire and just place the jumper plug back in to the Battery Protect.

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platypus avatar image platypus commented ·

That makes total sense - thank you!


But if both devices are bluetooth enabled and connected via the VE.Smart Network, I assume this step is unnecessary

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