Date:         Fri, 30 Jan 2009 10:50:35 -0500
Reply-To:     David Beierl <dbeierl@ATTGLOBAL.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         David Beierl <dbeierl@ATTGLOBAL.NET>
Subject:      Re: 12V power inverter ?
Comments: To: Michael Sullivan <sandwichhead@GMAIL.COM>
In-Reply-To:  <eccfedcc0901300641m3dc485e1s8eed5cb7359dc410@mail.gmail.co m>
Content-Type: text/plain; charset="us-ascii"; format=flowed

At 09:41 AM 1/30/2009, Michael Sullivan wrote:
>Power requirements 110-127v (+/-10%)
>Rated current 3.5 amps
>Power consumption (average in watts)
>Printing 250W

Michael, this says that your printer (must be a laser, something like
my hp 1200) consumes an *average* of 250 watts while printing, so
clearly you will need something that delivers that much power.

But it's not that simple.  Inverters have a wattage rating and a
volt-amperes rating, which is larger.  This is often the number
advertised as "watts."  Your printer has a rated current of 3.5 amps
at 99-140 VAC.  Taking the worst case, 140V times 3.5A is just under
500 volt-amps.  More typical case at 115 VAC would be 400
volt-amps.  So minimum peak capacity of the inverter would be say
four amps or 450+ volt-amps, and minimum sustained capacity say 300 watts.

Amazon will sell you a cheapish device called a Kill-A-Watt which
will let you measure the average wattage and volt-amperage of the
printer directly, on line current.  I'd check with the maker before
hooking it up to an inverter output.  I doubt it would smoke, but the
readings might be off.

Maybe better to get an inkjet...

--
David Beierl - Providence RI USA -- http://pws.prserv.net/synergy/Vanagon/
'84 Westy "Dutiful Passage," '85 GL "Poor Relation"