The Kill A Watt linked to is simple and effective. It can give you a
readout of total KWH used when the proper button is pushed, It does reset
itself upon power loss, so it only reads you the power settings for your
current session. It cannot remember which function is selected between
sessions. It also has a 1200 watt limit. Above that and it begins to
overheat. For these reasons I have decided it is unsuitable for full-time
use in a campervan, although it is great for occasional usage metering.

There are more expensive Kill A Watt units that are be better for camper
vans having a built-in memory and more features. I bought one a few years
ago but it only lasted a short time and broke when the warrantee ran out.

-- Gnarlie

On Mon, Jun 2, 2014 at 7:01 AM, Harry Hoffman <hhoffman@ip-solutions.net>
wrote:

> So, for plugging into a 120V mains there's the kill-a-watt:
>
> http://www.p3international.com/products/p4400.html
>
> Cheers,
> Harry
>
>
>
> On Jun 2, 2014, at 8:56 AM, JRodgers <jrodgers113@GMAIL.COM> wrote:
>
> > Please rely off list to my request.
> >
> >
> > I am in need of an electrical cost calculator - a box of some type that
> > will give me a digital readout of electrical power consumption and total
> > cost in dollars of cents for power consumed. Obviously this will need to
> > be programmable for cost per kilowatt to readout in dollars. I need to
> > plug a piece of equipment into the box and get a readout for each total
> > operating period of the equipment.
> >
> > Anyone know of these things - or where I might look - or how I might
> build.
> >
> > Please respond off list.
> >
> > Thanks.
> >
> > John
>