[C320-list] Help, Please with this questions: What is theminimumgenerator wattagenecessary to efficiently run my 30AMPonboard charger?

[Jeff Hare]

Hi Guy,  

I suspect Dick's referring to the shore power charger being a 20a unit. (20a DC out). 

Given that and a half discharged pair of flooded 4Ds, it will take about 10 hours to restore the 180amp hours needed *fully* recharge those.  The honda and a shore power plug will be the same. 

With a 75 balmar externally regulated alternator you bring this time down to about 5hrs for full charge because it will be able to feed close to 50a into the batteries for the first 30-45 min or so.  After that the batts won't take that much current and the charging process slows down a lot. 

With a 40a shore charger and a pair of AGM batteries, the honda would be able to do the same job in about 3-4hrs.  Mostly because AGMs will accept a much higher charge current for a much longer period of time.  Meaning more Amp Hours in faster.  

I like the honda idea, its great insurance when cruising.

-Jeff

-----Original Message-----
From: "Guy Henry" <guyhenry22 at aol.com>
Date: Mon, 24 May 2010 08:17:53 
To: <C320-List at Catalina320.com>
Subject: Re: [C320-list] Help, Please with this questions: What is the
	minimumgenerator	wattagenecessary to efficiently run my 30
	AMPonboard charger?

I think we're mixing AC and DC amperages.
I have the Xantrex 20 amp (DC) charger and use the Honda 2000 - 20 amps (AC)
The Honda has an eco drive throttle that only throttles up under demand.
The charger has never caused the Honda to run at anything over the slowest
idle.  I can run the charger for 15 hours on a tank of gas.  The tank has a
sealing cap on it for when not in use.  

Guy 
MoonShadow #115
 

-----Original Message-----
From: c320-list-bounces at lists.catalina320.com
[mailto:c320-list-bounces at lists.catalina320.com] On Behalf Of Dick Walker
Sent: Sunday, May 23, 2010 12:13 PM
To: C320-List at Catalina320.com
Subject: Re: [C320-list] Help,Please with this questions: What is the
minimumgenerator wattagenecessary to efficiently run my 30 AMPonboard
charger?

HI from Coronado,

I decided not to get a Honda since I have a 20 amp charger so the fasest I
can charge is 20 AMPS.  The Honda also requires gas and where to srore it
and the gas.  My solution was to get the Balmar alternator and charger
monitor.

If we are on the hook I can run the engine 30 minutes in the morning and in
the evening and the batteries will stay charged and it will also produce all
the hot water we need.


Dick Walker
WindWalkerII #687
619.435.8986



-----Original Message-----
From: c320-list-bounces at lists.catalina320.com
[mailto:c320-list-bounces at lists.catalina320.com] On Behalf Of Robert E.
Sloat
Sent: Sunday, May 23, 2010 6:13 AM
To: C320-List at Catalina320.com
Subject: Re: [C320-list] Help, Please with this questions: What is the
minimum generator wattagenecessary to efficiently run my 30 AMP onboard
charger?

The specs. for my Xantrex 20 amp charger on hull 894 requires 4.6 amps from 
120 volts so the amp requirement is about 550 watts on the AC side.  Check 
out the Honda site where there is a guide for size of generators needed for 
various AC loads.  There is the issue of inductance loading which is a heavy

load start up phenomenon which can easily double the wattage requirement. I 
don't think it applies to a Xantrex type device.

The other items raised including hot water heater, air conditioning and 
other electrical devices which will be a temptation when an AC source is 
available away from the dock should be factored into the generator sizing 
decision.

I have the very light Honda 2000 which I used for emergency backup at home 
for small sump pumps and powering electrical hand tools at remote locations.

It is very quiet and fairly light.  I don't bring it on board and think you 
would have to figure out where to safely store gasoline and the charger when

under way.  I can't imagine a 1 or 2 gallon tank of gasoline to feed the 
generator sitting inside my boat when things get rough.  I guess you could 
lash the tank to the stern.


Bob Sloat
Savannah Hull 894
----- Original Message ----- 
From: "Rick Sulewski" <rsulewski at bex.net>
To: <C320-List at Catalina320.com>
Sent: Saturday, May 22, 2010 11:20 PM
Subject: [C320-list] Help,Please with this questions: What is the minimum 
generator wattagenecessary to efficiently run my 30 AMP onboard charger?


> Help, please!
>
>
>
> Understanding that there have been discussions from time to time about the
> size of the portable gasoline chargers to run the onboard chargers (I have
> 30 amp unit on my 1995 320), has anyone figured out the minimum wattage
> generator needed to efficiently run the charger?
>
>
>
> I am considering if it is best to go with a 42 lb Yamaha 2000
> inverter/generator rated at a max of 13.5 amps and 1,600 watts, or the 27 
> lb
> Yamaha 1000 rated at a max of 8 amps and 900 watts.
>
>
>
> I considered a larger Yamaha inverter/generator with a max 21 amp and 2400
> watts to run the 16.5K AC/Heat unit, but I understand that the weight 
> jumps
> to about 70 lb and is much too large and bulky to store in the aft corner
> storage lockers.
>
>
>
> Thanks for your help.
>
>
>
>
>
> Rick
>
> My-Ria #277
>