Battery Charger

[Ken Juul]

Got the electrical part done, will mount the new Promariner 30 amp charger tomorrow.   8+ year old Xantrex Trucharge 20+ died.  Talked with Mainesail about which charger to buy.  In the discussion he mentioned that sometimes a current spike will fry the diodes in the charger.  That got me thinking.  Perhaps I killed the trucharge by starting the engine while the honda 2000 was charging the batteries.  Will never know for sure but from now on I'm going to make sure there is only one thing charging the batteries at a time.

[Ron Hill]

Ken : I've posted it a number of times -- that I never thought it was a good idea to start the engine while shore power charger was charging (Honda is charging thru the shore power wiring).  

You have two different sources trying to charge the same batteries - at the SAME time - why??.

You just may have proven my point!!  A thought

[Ken Juul]

Amen...may no one else have to deal with it

[mainesail]

Ken : I've posted it a number of times -- that I never thought it was a good idea to start the engine while shore power charger was charging (Honda is charging thru the shore power wiring).  

You have two different sources trying to charge the same batteries - at the SAME time.

You just may have proven my point!!  A thought

This is absolutely not the issue. You can have ten items charging batteries and they won't care provided the voltage is regulated.

The problem is that when using two outputs and the diodes are actively flowing current into the banks, and you hit the starter button the in-rush and resulting voltage will sag on the starting bank will and try to pull current from the other bank through the output diodes backwards. Some charger manufacturers used some real elcheapo diodes on the outputs and this can, on occasion, happen. While it is quite rare it does happen on some chargers... You could do the same with a bow thruster or windlass if the charger was working and supplying two banks and both of these are non-charging sources.....

[lazybone]

"Ample Power" the manufacturer of my alternator and smart regulator specifically warns in bolder type in their instructions to not have a 110v charger operating while  starting the engine or running the engine.

[Ron Hill]

Thanks Aldo!  
I still think its not a good idea to start the engine with the shore power charging!

[Jeff Tancock]

Not wanting to hijack this thread but my 20 year old StatPower Truecharge 40 (before they became Xantrex) burned up it's circuit board in December as I sat there having a beer with a buddy. I read lots of info on the board including Mainesails stuff and was about to get myself one of the recommended chargers when I came across an old/new in the box yellow Xanrex 20+ private sale for a considerable discount.It seems that these were well thought of so I grabbed it. When I went to install I realized that some codes have changed. I am pulling the household wiring on the AC side from the previous install and replacing with 14 AWG multistrand and it appears that I need to install a fuse or breaker near the battery. I am having a hard time figuring out the size of a fuse and not sure want would be the easiest/cheapest.

ANL or terminal block? Any other options?
What size ie amps?????

Anyone have a suggestion for me?
I have 2 golf carts for house and a 12V back up both to be wired to the charger...
Thanks!

[sailaway]

Jeff 14awg wire is rated 15 amps. If you can find a marine grade breaker they are a lot better than chasing down a fuse when it blows.Charlie

[Jeff Tancock]

Thanks Charlie....but the 14 multi strand is what is code for the AC power source tied into a 15 amp breaker, what I am having trouble with is the DC outputs going to the batteries and them now needing a fuse or beaker.

[Ken Juul]

The DC output of the 20+ is 20 amps. I used a 30 amp for all the years mine worked.  Now that I've upgraded to a 30 amp unit...it is harder....at least in the Fla Keys... to find the proper sized fuze.  For now I'm still using the 30amp slow blow fuses.  Need to put new one in about every other day.  Eventually will find a 40 amp fuse/CB that I can retrofit.

[John Langford]

West Marine (and others i assume) sell a really nice fuse block which fits right on the positive terminal of the two battery sets you are charging. I have  Xantrex 20+ and I use 30 amp fuses in the fuse block.