Charge controller to buss or straight to battery

[wingssail]

Originally Posted by docrn

In the process of installing solar on my boat. Is it acceptable to run the output from the charge controller to the positive buss or does it have to go straight to the battery? I’ve seen both but thought it was always recommended to go straight to the battery.

Thanks

There will be many opposing views on this.

I run the solar output to the positive bus, with its own switch.

The shore power battery charger also goes to the positive bus, also switched.

The alternator output also goes directly to the positive bus.

The cables from the batteries to the switches are heavy, 2/0.

The output from the charging sources can then be directed to either battery, or both, under my control.

I am a believer that only one wire should be connected to the positive post on the battery, that that goes directly to the battery switch. All loads, and all charging sources, go from the positive bus through the switch to the batteries.

Among other things, this allows the batteries to be completely isolated if desired, with a simple change of the switch position.

This also means that I have to accept the responsibility of correctly managing charging and switching the batteries myself.

[svfinlandia]

Originally Posted by docrn

In the process of installing solar on my boat. Is it acceptable to run the output from the charge controller to the positive buss or does it have to go straight to the battery? I’ve seen both but thought it was always recommended to go straight to the battery.

Thanks

It seems to me that a very easy way for a rough check of the resistance between your positive battery terminal and your positive bus is to the first measure the DC voltage between the negative and positive terminals of your battery and then measure the voltage between the negative pole of your battery and your positive bus. If the voltage reading is the same or very very close, no problem at all.

Al, S/V Finlandia

[Nico Domino]

Originally Posted by docrn

In the process of installing solar on my boat. Is it acceptable to run the output from the charge controller to the positive buss or does it have to go straight to the battery? I’ve seen both but thought it was always recommended to go straight to the battery.

Thanks

Probably to the battery direct, as the controller requires power supply to work. If you switch your power off when leaving the boat,the charger shuts down. ( most of them )
I have two banks and they are connected to twin battery bank charger, giving priority to start battery and when 90% switches to house. This way ,always enough power to start engine.

[Nico Domino]

Originally Posted by docrn

In the process of installing solar on my boat. Is it acceptable to run the output from the charge controller to the positive buss or does it have to go straight to the battery? I’ve seen both but thought it was always recommended to go straight to the battery.

Thanks

Probably to the battery direct, as the controller requires power supply to work. If you switch your power off when leaving the boat,the charger shuts down. ( most of them ) some chargers reset themselves to default when depowered
I have two banks and they are connected to twin battery bank charger, giving priority to start battery and when 90% switches to house. This way ,always enough power to start engine.

[mitiempo]

Originally Posted by Nico Domino

Probably to the battery direct, as the controller requires power supply to work. If you switch your power off when leaving the boat,the charger shuts down. ( most of them ) some chargers reset themselves to default when depowered
I have two banks and they are connected to twin battery bank charger, giving priority to start battery and when 90% switches to house. This way ,always enough power to start engine.

If the buss is a charge buss as it should be the solar connections should go to it. Batteries deserve the fewest connections possible. From house bank positive to the buss, with all charge sources connected and from there to the switch.

What charger do you have that knows when your start battery is at 90% SOC? All multi bank chargers I know of supply current and the battery most in need takes the bulk of the current with the other(s) taking less as needed.

[Uncle Bob]

Originally Posted by Sailmonkey

Did you read the original question?

More to the point, did ken understand the original question?

[aa1bflyboy]

Originally Posted by tarian

I wire to the bus bar with adequate fuse just before it clearly the wire from busbar to battery is capable of this common sense I suppose

Some folks told God they already have enough money when He was handing out common sense. I said I’ll take all I can get and He gave me a pocket full and said keep the change.

[Nico Domino]

Originally Posted by mitiempo

If the buss is a charge buss as it should be the solar connections should go to it. Batteries deserve the fewest connections possible. From house bank positive to the buss, with all charge sources connected and from there to the switch.

What charger do you have that knows when your start battery is at 90% SOC? All multi bank chargers I know of supply current and the battery most in need takes the bulk of the current with the other(s) taking less as needed.

See attachment,

[mitiempo]

Originally Posted by Nico Domino

See attachment,

What is that supposed to mean. Same as any solar controller really.

[kmacdonald]

I wired mine to the battery side of the house battery switch. It's fused for 10 guage wire. The battery to switch is fused for 1 guage wire. Well it's actually fused for bigger wire because it caries starter current but will blow before wire damage or fire if shorted. ANL 250 amp I think. Maybe 300 amp. Unless the fuses are blown the solar is always on.

It will varry with boat depending on battery location, charge controller location, and main switch locations.

[pwillems]

You might consider adding a "charge" bus separate to your "load" bus with it's own cable to the battery.

Just future proofing for a lithium battery upgrade if you ever go that route...