PowerCost Monitor

[Tom Metro]

Ted Roche wrote:
>> It uses an optical sensor that sits on your meter.
> 
> It seems like quite a Rube-Goldberg way to do business.

Yeah, but...


> Is there a problem with wrapping a clamp-on ammeter around the
> incoming power cable to the breaker box?

A few problems. The wires are usually inaccessible in a conduit, and 
when they are accessible, they're usually in a jacketed cable. To use a 
clamp-on ammeter you need to put the clamp around only one of the legs.

You can usually accomplish this if you're willing to open up the breaker 
box. But that isn't exactly consumer friendly.

The real question is why doesn't NSTAR sell a low cost wireless reader 
that picks up the signals from the digital utility meters. You'd think 
they would, given that they supposedly want to encourage power savings.


Mark Richards wrote:
> There are several AC ammeters that deliver a stable DC voltage 
> proportional to current.

I used to have a current clamp with DC output attached to one of my AC 
lines, but I never really used it for much other than the occasional 
manual sampling. I never bothered to hook it up to anything to do 
automated logging.

  -Tom

-- 
Tom Metro
Venture Logic, Newton, MA, USA
"Enterprise solutions through open source."
Professional Profile: http://tmetro.venturelogic.com/

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