[C320-list] Inverter - follow-up questions

Wed Mar 11 23:41:22 PDT 2009

Here's my last input on this one, no pun intended. 

The detraction (for me) with the external generator approach on a C320 is
that you have to store it, haul it out, connect it, keep it fueled, and put
it away when actually sailing, which after all is the primary purpose of the
boat. I'm sure these things are not monumental tasks and if you are going to
be moored or anchored for many days at a time it might be worth it but for
me the simplicity of having a battery powered inverter is more attractive.
Actually, the main reason I installed my inverter/charger is that I had an
OEM Pro-Mariner charger which I've heard can fail and kill your batteries. I
installed a small Magnum Energy MMS1012 1000W pure sinewave inverter/charger
which actually fits in the same place that the original charger was located
without any additional wiring except for the AC lines back to the AC
distribution panel. I got an unbelievably good price on mine (I think it was
a mistake) but I think they go for about $1100, which admittedly is a lot
more than the price of a battery charger only. It has temperature
compensated battery charging (probably pretty standard nowadays) which my
original charger did not have and I wanted badly when I replaced my original
flooded batteries with (more expensive) AGMs. Actually, I have yet to
actually use the inverter function but I know it works. If you're only
planning on using a couple hundred watts of load (TVs and such) I think an
inverter like I have is the way to go. Note: I don't have a microwave oven,
so that might lead to a different conclusion. 

The concern over running a diesel engine for a couple or hours a day to
recharge batteries is unfounded as they should last at least 10,000 hours
minimum. Okay, if you're a cruiser and run your engine an extra 2 hours
charge every day it might be a concern. But in that case maybe you should
have a larger boat with an internal generator, or at least solar panels.

CR Ashley
Rosebud C320 Hull #882

-----Original Message-----
From: c320-list-bounces at lists.catalina320.com
[mailto:c320-list-bounces at lists.catalina320.com] On Behalf Of Dean Vermeire
Sent: Monday, March 09, 2009 7:50 AM
To: C320-List at Catalina320.com
Subject: Re: [C320-list] Inverter - follow-up questions

Thanks.  That's pretty much what I figured.

At this point, I'm thinking a long extension cord from the boat to the dock
is good enough for me.

crashley at gte.net wrote:
> Dean,
>
> I'm not sure anyone answered this but here's one for you.
>
> An inverter converts 12 VDC from the battery to 115 VAC @ 60 Hz (in the
> U.S.) for the AC loads like a microwave. Most inverters also provide a
> battery charging function when they have an external source of AC (like at
> the dock).
>
> The generator option (which I don't have) has the advantage that (when it
is
> running) it provides 115 VAC for the AC loads and can run the on-board
> battery charger as well. It's true that running the boat's engine does
this
> too, but the efficiency of the generator is probably better. The generator
> also uses a different fuel, gasoline, which you probably need on the boat
> anyway if you have a gasoline engine for the dinghy outboard. Cost-wise
I'm
> not sure which one is better but inverter/chargers cost upwards of $1000
> (sometimes a lot more) and also usually require some additional heavy
gauge
> DC cabling to be added depending on where you locate it. The external
> generator is more of a "plug and play" approach. 
>
> CR Ashley
> Rosebud C320 Hull #882
>   
>
>  
>
> -----Original Message-----
> From: c320-list-bounces at lists.catalina320.com
> [mailto:c320-list-bounces at lists.catalina320.com] On Behalf Of Dean
Vermeire
> Sent: Wednesday, March 04, 2009 9:32 AM
> To: C320-List at Catalina320.com
> Subject: [C320-list] Inverter - follow-up questions
>
> Hi again.
>
> Thanks for all the good input so far.  I hate to ask really stupid
> questions, but somebody's got to do it.
>
> It seems to me that I've got two choices - put in an inverter that takes
DC
> from the batteries and runs them down while converting to AC, or put in a
> generator that uses some other energy source to run a motor that generates
> AC.  I look at the existing systems onboard, and I see a diesel motor that
> runs an alternator that produces DC to recharge my batteries.  I also have
> shore power (AC) that recharges the batteries by way of a battery charger,
> which I see listed in catalogs as a "battery charger / inverter".
>
> Stupid question #1:  Are they calling the battery chargert an inverter
> because it is changing AC to DC?
> Stupid question #2:  Why is a generator less expensive than a DC-to-AC
> inverter, when the generator must have similar circuitry in it?
>
> Thanks,
> Dean Vermeire
> Moonstruck II (#847)
>
>
>
>
>
>
>   