Yea, it can be hard to follow at times, especially when we're talking about electrical wiring!
Wiring solar and ACR’s
- Thread starter fred1diver
- Start date
does this make any sense? Am I forgetting something?
my charger has 2 leads, with the ACR in place I guess I will only need one
@fred1diver I have read that all charging sources should be run to the largest battery (typically the house battery) and then the ACR takes care of charging the other battery. That is the way I set up my system, solar, shore charger and alternator are all connected to the house bank, the starter battery is only charged through the ACR or by switching to Both in the 1/2/B switch.
I know it’s an old thread, just have been busy with other aspects of the boat, the solar is wired, no problem there, the m-ACR is the next step, a big one as I need to redo most of the battery wiring, my question tonight is this, what gauge wire should I use to wire the ACR and what fuse size is needed ?
I have found many schematics on how to wire it, but none speak about wire and fuse size.
I will be going to my local chandlery tomorrow morning to get the missing pieces.
what does the SI connection do and where does it connect?
I have found many schematics on how to wire it, but none speak about wire and fuse size.
I will be going to my local chandlery tomorrow morning to get the missing pieces.
what does the SI connection do and where does it connect?
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The easy question first. The SI or Starter Interrupt breaks the connection between the house and start batteries when the start button is pushed. When the starter engages there is a surge of current through the system the SI prevents this from happening.
Fuses protect the wire, so they should be sized accordingly.
Wire size is based on acceptable line loss, i.e., 3% or 10% voltage drop over the round trip distance. The ACR has a max current limit, check the manual. The wire should be sized to safely carry that load or the maximum amperage the charge sources can supply.
Here's a link to the Ampacity tables.
Fuses protect the wire, so they should be sized accordingly.
Wire size is based on acceptable line loss, i.e., 3% or 10% voltage drop over the round trip distance. The ACR has a max current limit, check the manual. The wire should be sized to safely carry that load or the maximum amperage the charge sources can supply.
Here's a link to the Ampacity tables.
The short answer to your question is, connect the MPPT charger output to the same place that your current 110VAC shore power charger output is connected to. They have blocking diodes so they will not be damaging each other. The one with the highest voltage will charge your batteries. All other wiring can remain as is.
Upon re-reading this post, it is unclear. The SI prevents the surge from going through the ACR. It does not prevent the surge resulting from engaging the starter. If the surge goes through the ACR it can damage the ACR.