Originally Posted by SV Rosy
I'm assisting a friend that is at sea on his Oceanis 41 2015 and has an electrical
It seems that batteries are discharging faster than usually with a given load.
Batteries has been individually isolated and keep there voltage. So We assume battery are in good condition. (They were replaced 8 months ago)
At the boat Monitor
, Voltage shows max 12.5, while portable voltmeter read more than 13.5 direct in batteries while charging
panel or alternator
recharge ends, the voltage drop around 12.3-12.5Volts.
Could it be a known problem that some of you had on a Beneteau
Oceanis of 2015 era?
Any help would be greatly appreciated.
There is no benefit from looking at model-specific issues.
Start by chasing the difference between 12.5V at battery monitor and 13.5V at battery terminals. If you want to get this right then take no shortcuts.
Draw a schematic showing every piece that connects the positive terminal of the house battery to the positive terminal of the battery monitor.
Then do the same on the negative side.
Then, starting with battery at lowish state of charge, run engine
and measure voltage drop between negative terminal of house battery and negative terminal of battery monitor. Then measure drop in each piece in between negative terminal of house battery and negative terminal of battery monitor. The sum of all the component drops on negative sideshould add up to the total drop on negaitive side. Do the same on positive side.
Now identify the largest component drop. At one of the ends of that piece there is a bad connection, which will be be hot to the touch (and show itself with an infrared camera). Clean and tighten that connection and repeat.
Usual suspects are: a) ground point at engine
b) combiner relays or diodes.