electrical systems crash

splax

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Nov 12, 2012
692
Hunter 34 Portsmouth
So if the charger is rated at 20 Amps AC that would be fine...
 
Oct 29, 2016
1,915
Hunter 41 DS Port Huron
Rated at an input of 20 A @120 VAC would produce 2400 Watts/voltage output minus efficiencies.
 
Dec 25, 2000
5,702
Hunter Passage 42 Shelter Bay, WA
I don't understand how having a charger rated for 100 Amps does any good powered by a circuit rated for 30.
Our boat, like many others of the same size or larger, consists of two 30 amp shore power connections. Seldom ever connect both cords and just manage power consumption to one 30 amp circuit. It also has an 8KW Genset that produces around 60-70 amps. This might help explain the need for a 100 amp charger.

Hunter equipped the original boat with a 1,600 watt inverter/charger. When it came time to replace it they advised me to go with a 2,500 watt unit. They said it would be friendlier for the boat, so that is what I did and thus far has worked quite well since installed around 2003.
 
Oct 29, 2016
1,915
Hunter 41 DS Port Huron
which would be 200 A DC, minus losses, yes?
Yes, but, like @Stu Jackson put it, this is not how charger/inverters are rated. I just used that as a simple conversion for the relationship from one voltage to another. For instance the Freedom 20 refers really to the capacity of the inverter being 20 A @ 120 VAC while during its max charge rate of 100 ADC @ 12 V it draws 21 amps @ 120VAC as this is the size of the transformer and its related circuitry if that makes any sense.
 

splax

.
Nov 12, 2012
692
Hunter 34 Portsmouth
I do understand completely, however to a breaker or fuse 20 A is 20 A whether DC or AC. My immediate read was the internal protection level of the device.
 
Feb 6, 1998
11,665
Canadian Sailcraft 36T Casco Bay, ME
I don't understand how having a charger rated for 100 Amps does any good powered by a circuit rated for 30.

It is simple. If you follow Ohm's Law and use; Watts = Amps x Volts

The 30A input is at 120V
The output is 100A at 12.0V

A typical 30A Shore Service = 30A x 120V = 3600W
A typical 100A DC charger = 100A x 12V = 1200W x 1.15 (charger inefficiency) = 1380W
 
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splax

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Nov 12, 2012
692
Hunter 34 Portsmouth
So I got down to my boat to see what I had. I think it is a pro-mariner tournament 200. I decline to crawl into the cellar right now to verify. Apparently it does 20 A DC split between the starter battery and the house bank of 2 122 AH 12V batteries wired in parallel. So I guess I need to upgrade.
 
Feb 26, 2004
22,759
Catalina 34 224 Maple Bay, BC, Canada
I think it is a pro-mariner tournament 200.
For those who may not know, old "ProMariner" units should not be confused with the newer Promariner chargers which are very good, the ones identical to the Sterling chargers. The old (and perhaps defunct) company made really crappy stuff.
So I guess I need to upgrade.
Yes, here's why:

Pro Mariner Flyback Chargers

Get them off your boat. They are a FIRE HAZARD

Reply #6:

http://c34.org/bbs/index.php/topic,3716.0.html

How Many Times Do We Have to Warn You?

http://c34.org/bbs/index.php/topic,5179.0.html

While Terry seems to think his problem was with lightning, it sure seems that having to go through so many ProMariner chargers is still OK. Nonsense! Read all the links in Reply #3 and Reply #5 and your head will be spinning until next month!
 
Jan 12, 2011
930
Hunter 410 full time cruiser
Battery chargers on a lot of Hunters depends on the option selected. For my 410 the standard battery charger was a kind of stupid 30A unit and i think the alternator a 60a unit. But if you got the the “inverter” option the boat had a 100a charger with a 2000w inverter and a 100 amp alternator. Had the same batteries either way.
 
Jun 1, 2009
1,735
Hunter 49 toronto
Thanks all, enlightening, Daydreamer and Mainesail. I do have the original from Hunter xantrax freedom 20 which book states that it has a 20amp charger and 2000w inverter. Is it 20 amps or 100 amps as stated by others? Best I can tell these boats came with one 4d agm... the other 2 were either options or additions but all three are professionally installed. Artboas..what 6v AGM's did you choose? Also I have a email sent to Marine How to about charger and house batts.?? Thanks, I am feeling better for a minute
I went with East Penn AGMs. They are wonderful!!!!
I highly, and thoroughly suggest you go with 6v batteries. And for engine start, a deep cycle 12v. M
Many years ago, I was a Xantrex owner. I had such awful customer support, I swore I’d never go back.
Go through these posts, and everyone will tell you that their experiences with Magnum Energy are first rate.
I would suggest the 2812. You could get by with one level down, but it’s not worth the saving. It’s a set & forget system.
When you install it, call Magnum for setup support. They are a pleasure to deal with.
Good luck!