Need Help w. My General Electrical Setup

San_Diego_SeaRay

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I bought a 27' Chaparral last January and immediately started rebuilding the engine, outdrive, and transom assembly. Well I'm finished w. all that now and I'm realizing I kind of forgot to note the electrical layout.

As you can see from the pictures, I have two starting batteries that are routed to a four position Perko battery switch. Then there's one power wire that gets routed from the four position switch to a two position Perko. This "red" Perko controls the House battery. This is where my confusion comes in as I forget exactly how this section was connected. I'm about 90% certain that the red power wire coming out of the red Perko was mounted to the House Battery positive. And then there was a red power wire coming off that same battery terminal routed to the + on the inverter. Then there was black power wire routed from the House Battery negative to the negative side of the inverter.

Here's my confusion:
  • With this setup wired as above, it seems that the purpose of the house battery is to supply the inverter w. power, so that if you set the red Perko to "off" then you could still run A/C on the boat?
  • I imagine the red Perko must be "on" while the engine is running so that the alternator can recharge all 3 batteries, not just the starting batteries?
  • If I stop my engine and leave the black Perko to "all" and the red Perko to "on", doesn't that mean that all 3 batteries will then be supplying electricity to the boat? Is it expected that you should set the black Perko to "off" and the red Perko to "on" to only use the house battery?
  • Should the negative on the house battery somehow be connected to the engine as well?

EDIT: You can't actually see the house battery; it will be tucked away almost mid-cabin down the starboard side.
 

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alldodge

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First all grounds go to ground, including the house and two starter bats, otherwise you need an onboard charger just to charge the Inverter (house) bat. Lets call your bats as follows, 1) Start 2) House 3) Inverter, this way we can keep things straight. The normal configuration for batteries is, one start and one house as shown below.

Looking at your pics I see where an inverter bat was added to the mix. So unless the house bat wiring was also moved, this would be the case.

The inverter bat is connected to one of the two terminals on the 4 position switch. This means that the switch needs to be in All or in the same position as the feed to the inverter to charge the two. So if the Inverter bat is connected in position 2, then once stopped, switch the switch from All to position 2 so the start bat is no longer effected.

In short, you have two house bats when in position 2 and the Inverter bat switch is ON

If you use an meter, you can determine which one is which by switching positions and taking readings.

Two Bat one switch.jpg

You could add an ACR to fix all your charging issues and not have to pay any attention to switch placement unless needing an additional bat to help start motor
 

San_Diego_SeaRay

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Nov 9, 2014
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Thanks for your detailed reply! :)

First all grounds go to ground, including the house and two starter bats, otherwise you need an onboard charger just to charge the Inverter (house) bat.

Ah. Very helpful!

Lets call your bats as follows, 1) Start 2) House 3) Inverter, this way we can keep things straight. The normal configuration for batteries is, one start and one house as shown below.

Interesting! I thought I had two starting batteries, where one is used as a back up to the other. But you're saying that those two batteries in the picture are actually a starting battery and a house battery? And then the last one is a dedicated "inverter" battery...well I learned something.

The inverter bat is connected to one of the two terminals on the 4 position switch. This means that the switch needs to be in All or in the same position as the feed to the inverter to charge the two. So if the Inverter bat is connected in position 2, then once stopped, switch the switch from All to position 2 so the start bat is no longer effected.

In short, you have two house bats when in position 2 and the Inverter bat switch is ON

If you use an meter, you can determine which one is which by switching positions and taking readings.

I see. So, basically by checking for continuity I might determine that the house battery and the inverter battery work together if the red Perko is "on".

You could add an ACR to fix all your charging issues and not have to pay any attention to switch placement unless needing an additional bat to help start motor

Yep. I've been looking at possibly integrating one of those into the system. Where would you put it exactly? Between the black and red Perkos I'd imagine?

So because I thought my inverter battery was a "house" battery, I bought a sealed AGM battery. Do you see any problems using that type of battery for the inverter?
 

alldodge

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Interesting! I thought I had two starting batteries, where one is used as a back up to the other. But you're saying that those two batteries in the picture are actually a starting battery and a house battery? And then the last one is a dedicated "inverter" battery...well I learned something.

I'm saying in most cases it would be a house and start bat. Not saying it is but looking at your pic, it appears this would be the case. The breaker panel shows, breakers for Fridge, Macerator, Helm and others.

fetch


{quote=]I see. So, basically by checking for continuity I might determine that the house battery and the inverter battery work together if the red Perko is "on".[/quote]

Disconnect the bats, and read continuity of the red cables. I'm guessing the cable going to the Inverter bat (with switch turned ON) will not be disconnected to one of the other bat by the switch. Another method is remove the switch from the panel and see how the wires are connected

Yep. I've been looking at possibly integrating one of those into the system. Where would you put it exactly? Between the black and red Perkos I'd imagine?

Something like this which doesn't have the Inverter bat. Just keep the Inverter switch ON and all 3 bats will be charged, or a second ACR can be installed from bat 1 to the inverter bat
Two Bat one switch and ACR.jpg
So because I thought my inverter battery was a "house" battery, I bought a sealed AGM battery. Do you see any problems using that type of battery for the inverter?

No there will be no issue using the AGM with the alternator charging system. Now if the boat has an onboard charger and you will keep it plugged in for long periods then there is an issue. Lead acid and AGM charge and float at different levels. If you have an on board charger you could let it charge bats start and house, then get another AGM charger for the Inverter bat. All bats should be of the same type to use the same charger

What kind of charger do you have?
 

San_Diego_SeaRay

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Nov 9, 2014
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No there will be no issue using the AGM with the alternator charging system. Now if the boat has an onboard charger and you will keep it plugged in for long periods then there is an issue. Lead acid and AGM charge and float at different levels. If you have an on board charger you could let it charge bats start and house, then get another AGM charger for the Inverter bat. All bats should be of the same type to use the same charger

What kind of charger do you have?

I actually don't have a charger (there's a charger installed but it relies on shorepower). The boat is kept at a boatyard w. no access to electricity. I'm going to have to rely on the alternator to recharge all batteries during my outings. Not sure how that's going to work out.

I may have to consider installing a solar panel.
eek.gif
 
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