-----Original Message-----
Ron asks
Can the 4000W 24V inverter/charger be modified for 12V? I seem to recall
that Trace (prior to merger) was willing to customize units.

REPLY
That is how you get a 2500 watt unit.
The practice of modifying  or customizing individual units is cost prohibitive
unless the unit is designed specifically for  configuration changes by  the end
user.

The sheer task of tracking  all the various permutations and combination of
design features  becomes horrendous and only results in mass confusion.

Ron asks
Also, the Trace units are much heavier units. Am I wrong in assuming that
heavier is better?

REPLY
Yes.  Its like comparing a WW2 Sherman tank  with a late model Bradley APC
The Trace design relies on  line frequency switching at 60 Hz.
This requires big heavy  iron cored transformers. Eddy current losses  and
other design aspects limit performance.

Ron asks
Finally, if their quality was superior to Prosine, one could "stack" two 2500W
units.

REPLY
The Prosine 2.0 is stackable but the Prosine 3.0 was the first development and
stacking was not part of the design criteria at the time.
The Prosine 2.0 is the next design generation from the Prosine 3.0
However keep in mind that a major criteria was how to build it for less cost,
not necessarily how to make it much better in theory.

Having said that, there are many advantages to the new high frequency switch
mode designs as typified by the Statpower and  several other brands. It allow
for a lot of extra flexibility  and enhanced  operations that is just not
feasible with the older technology  except at an extremely high  cost.

Is there a down side? Yes just as there is a downside to having a modern Ford
compared to a basic Model T
What is your preference?  It cost more,  requires high tech to build and
sometimes requires more fussing to install.
But if you only want to run a light or a toaster or coffee make, no it doesn't
make a lot of difference.

But if you want to run a variable speed electric power tool, run your motors
cooler, have your batteries last longer, give you better power management data
concerning system usage and operation; then yes the new models have an
advantage.

I once had a 300 watt  inverter dating back to 1968 that weighed 10 lbs.
I now have a 300 watt inverter that weighs 1 lb and cost one tenth as much in
real dollars.

Ron asks
Is there another company or conglomerate who plays in this market?
Mastervolt and Vector (?) come to mind.

REPLY
There are many, probably too many to  enumerate here without missing someone..
Mastervolt and Victron are Dutch companies now entering the N.American marine
market with quality products
Vanner is an old established company, so is Analytic systems, as well as  Newmar
and Dimensions to name a few companies that have been around for more than 10
years.
Vector, Cherokee, Go power  and  many other compete in the low end  non sine
wave market.
Most of these are Chinese made, knock off copies or licensed copies of older
designs.

regards

Arild

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-----Original Message-----
From: Ron Rogers

I found another made by Xantrex after I clicked on a Charles Marine (good
company, but expensive) inverter. I am providing the URL Thomas, because it
lacks the detailed info you need. BUT, it says 3200W true sine-wave and
looks a little like a TRACE for $1999 with free shipping. I give up!

Comment

When comparing  products  be careful you are comparing apples and apples, not
apples and pears.

The older low frequency switching inverters like the Trace and Heart models
will have a lower output as the input voltage goes down.
The new high frequency switch mode types exhibit an inductive  operating mode.
As the input voltage goes down the unit compensates by increasing current draw.
This is good if you require stable and regulated output voltage.
But the downside is you must use good  DC wiring practice or suffer the
consequence.

A 2Kw Heart model might run okay with 1/0 cables but if you replace it with a
Prosine 2 Kw unit,  you will find the recommended cable size is now 2/0 for the
same installation. Will your coffee maker care. No!
But your home entertainment system or  expensive bread maker or fast charging
cam corder might.
You pays your money and takes you chances.  Go cheap or go best;  but you won't
get the best for the cheapest price.

All manufactures offer a range of products.  There is the low entry level basic
box and there are progressive improvements  up to the top end.

What you need to resolve is what level of reliability , and  functionality you
and your application is willing to  tolerate.
Once you know that then  look at how the company services the product and how
they resolve problems.

Do they repair or replace a product?  How difficult is it to remove and return a
given product  if it fails.
How complex is the installation and configuration procedures?
Do you need to read an inch thick manual before getting started.?
Is the configuration  options covered in  a few pages or  a few chapters?
How does a company service older models no longer part of their present product
offerings?

Can you reach knowledgeable service techs to answer your questions  when the
product does something  unexpected.

As is the case with buying a boat or any  other modern consumer product, the
informed  buyer is likely to get a better deal than the uninformed buyer.  If
you are not inclined to  become informed find someone whose judgment you trust
to do the homework for  you.

regards

Arild

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