How low to go with the voltage

[simonfraser]

Measure the voltage at the alternator, if it's only the 13.7v you mentioned earlier, that's not ideal, that won't fully charge the batteries. Check the solar controller output whilst you are at it. When taking readings, do the solar controller with the engine not running and the alternator with the solar controller disconnected (should be a fuse to pull). If your solar controller detects battery voltage (such as the Victron) disconnect the panel input to the controller, not the battery.

Tnx Paul,

The Solar takes it higher, 14.4 from memory, has a controller, I am not on the boat now.

But for a winters weeks electric, one regular overnight trip and other day lunch fixing stuff:
D2 25 hrs, bow thruster 30 secs, anchor winch 10mins (not that deep but often reset it)
LED lights, charging Ipad / phone /depth sounder on 20 hrs
Engine on 2hrs max

I poss just don’t generate enough for that lot during the winter. Trojans on order.

Can shore charge it too, will need 80m cable which I can make.
There is a mains powered charger on the boat.

Get a longer cable and shore charge it ?
keep an eye on the amps outgoing ?

What’s the best way to keep the new batteries healthy ?

 

[PaulRainbow]

Tnx Paul,

The Solar takes it higher, 14.4 from memory, has a controller, I am not on the boat now.

But for a winters weeks electric, one regular overnight trip and other day lunch fixing stuff:
D2 25 hrs, bow thruster 30 secs, anchor winch 10mins (not that deep but often reset it)
LED lights, charging Ipad / phone /depth sounder on 20 hrs
Engine on 2hrs max

I poss just don’t generate enough for that lot during the winter. Trojans on order.

Can shore charge it too, will need 80m cable which I can make.
There is a mains powered charger on the boat.

Get a longer cable and shore charge it ?
keep an eye on the amps outgoing ?

What’s the best way to keep the new batteries healthy ?

More solar would help, but i've got 230w and whilst they kept everything charged during the Summer, they need some help from shore power during the Winter (i'm in a marina).

If the alternator is only charging at 13.7v that's an issue. 13.7v is float charge, so isn't going to do much good running the engine for a couple of hours.

Shore power is a good solution but 80m cable is rather long, suppose it would be ok if you're not overloading it.