Mppt charge controller under load

[Deadboatbattery]

Hello
I am looking into charging two seperate lead acid boat batteries with solar.
My question is .
If I am charging my cranking battery and I crank my boat motor that pulls 80 amps in rush current. How does the charge controller react to this load?
Thanks

 

[Mattb4]

If it is not already putting out max charging amperage it will ramp up as the large load drops the DC voltage.

 

[Deadboatbattery]

If it is not already putting out max charging amperage it will ramp up as the large load drops the DC voltage.

Thanks
So i dont have to worry about burning anything up ?
Okay one more question.
If i use one solar panel and two charge controllers to charge each battery seperate , i assume if i select All on my battery isolator switch so boat batteries are connected both charge controllers will burn out ?
Thanks

 

[mikefitz]

charge controller react to this load?

The controller is limited to the solar power at its input. For example if you are getting 240 watts of solar power then 20 amps is the maximum 'solar' contribution to starting the engine, its the 12v starter battery that provides most of the current.

 

[mikefitz]

use one solar panel and two charge controllers

You cannot have two controllers connectec to one panel. Use one controller and a unit to 'share' the charge is common practice.

Argodiode Battery Isolators - Victron Energy

Make simultaneous charging of two or more batteries from one alternator possible, without connecting the batteries together. With Victrons Argodiode Battery Isolators.

www.victronenergy.com

One alternative would be to have a panel and controlley for each battery.
I guess at the moment you have a 3 position switch that selects which battery powers the boat electrics , house battery, starter battery or both.

 

[Deadboatbattery]

You cannot have two controllers connectec to one panel. Use one controller and a unit to 'share' the charge is common practice.

Argodiode Battery Isolators - Victron Energy

Make simultaneous charging of two or more batteries from one alternator possible, without connecting the batteries together. With Victrons Argodiode Battery Isolators.

www.victronenergy.com

One alternative would be to have a panel and controlley for each battery.
I guess at the moment you have a 3 position switch that selects which battery powers the boat electrics , house battery, starter battery or both.

Hi
Yes i have a 3 position switch.
While doing a search i came across an electrical engineering site where they were discussing charging two seperate batteries from one solar panel , using two charge controllers , one controller for each battery.
The only issue they saw was only one battery would charge untill the first one connected had fully charged the battery , then the second one would start charging the other battery.
I am just researching everything now.
Thanks

 

[Deadboatbattery]

The controller is limited to the solar power at its input. For example if you are getting 240 watts of solar power then 20 amps is the maximum 'solar' contribution to starting the engine, its the 12v starter battery that provides most of the current.

Thank you