Mainship 34 trawler (blt. 2006). Inverter battery bank charging question

[Roustabout]

I’ve owned this wonderful boat for 2 1/2 years, more than 2500 miles traveled. On The Loop now. Many more miles to go.

I don’t see that inverter batteries (four 12-volt FLA 228 AH each) are being charged by my main engine alternator (105 amp). The inverter batteries get charged by the inverter on shore power or generator. The Mainship owner’s manual does not show much about the inverter or the isolators (I have three) in the wiring diagrams. I would like to charge while under way from main engine alternator. I am thinking about getting a DC to DC converter from an isolator or alternator.

Do any of you Mainship owners have the main engine alternator charging your inverter batteries? If so please share how its done.

Thanks in advance

 

[Bmarler]

I’ve owned this wonderful boat for 2 1/2 years, more than 2500 miles traveled. On The Loop now. Many more miles to go.

I don’t see that inverter batteries (four 12-volt FLA 228 AH each) are being charged by my main engine alternator (105 amp). The inverter batteries get charged by the inverter on shore power or generator. The Mainship owner’s manual does not show much about the inverter or the isolators (I have three) in the wiring diagrams. I would like to charge while under way from main engine alternator. I am thinking about getting a DC to DC converter from an isolator or alternator.

Do any of you Mainship owners have the main engine alternator charging your inverter batteries? If so please share how its done.

Thanks in advance

not a mainship owner, but am pretty handy with electrical stuff. you mention three isolators. this seems a bit unlikely, maybe there are three automatic charge relays?
how many battery banks total? is there a programmable alternator regulator?
a little more information regarding the battery architecture would help us to help you.

 

[ranger58sb]

The Mainship owner’s manual does not show much about the inverter or the isolators (I have three) in the wiring diagrams.

I'd suspect your inverter was installed by a previous owner, not original to the boat.

-Chris

 

[Bacchus]

I removed my (2) MS installed diode isolators but don't have an inverter. My Bacchus website in projects section has a write up of my mods. Only change since has been moving my single start to my thruster bank to leave a pure house bank and I added batty monitor to house bank.
There are lots of ways to configure batty banks and IMO none right or wrong.

 

[SteveK]

I’ve owned this wonderful boat for 2 1/2 years, more than 2500 miles traveled. On The Loop now. Many more miles to go.

I don’t see that inverter batteries (four 12-volt FLA 228 AH each) are being charged by my main engine alternator (105 amp). The inverter batteries get charged by the inverter on shore power or generator. The Mainship owner’s manual does not show much about the inverter or the isolators (I have three) in the wiring diagrams. I would like to charge while under way from main engine alternator. I am thinking about getting a DC to DC converter from an isolator or alternator.

Do any of you Mainship owners have the main engine alternator charging your inverter batteries? If so please share how its done.

Thanks in advance

Sounds like you have an engine start bat, a GEN start bat, 4 inverter bats. Then one engine ALT 105A, with isolators (3). Assumming this is correct.

Your ALT should be adequate to charge all 3 banks. If one or more is not seeing a charge current then the suspect is a failed isolator. Why you would have three separate as opposed to one with 3 outlets needs to be explained. Maybe the GEN ALT goes to an isolator to also charge 3 banks. Maybe the inverter charger output charges 3 banks thru an isolator.

The main engine ALT should be charging the start bat and house bank through an isolator. Again I suggest if it is not then the isolator has failed.
As all Bats appear to be same type (FLA) and all charging sources set to FLA I am not sure why you would need a DC2DC charger.

 

[Bmarler]

why three isolators? one isolator with three outputs seems like how they would have done it.

 

[Roustabout]

Problem solved. Thanks to all for chiming in. With the help of a electrically skilled friend aboard for several days we found out that the inverter battery bank was indeed being charged, however, due to the mis-installation of a couple of negative cables going to the wrong place charging wasn’t occurring as intended. Now my Battery state of charge indicators and inverter are happy.

To answer the question about three battery isolators, two are powered by main engine alternator. The third one is only powered by the three bank battery charger.

 

[Bmarler]

Good news, thanks for updating the thread.