Electric sub-meter

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Could any one help in recommending a multi circuit sub-meter to monitor energy consumption in houses. and also low-cost submeters to monitor the HVAC compressor electric consumption (since I need many of them).
Thank you
H. Abaza

Abaza Hussein's picture
Joined: 2011-10-02
Reputation: 200


The 'kill-a-watt' is probably the cheapest household wattmeter out there, http://www.amazon.com/P3-International-P4400-Electricity-Monitor/dp/B00009MDBU/ref=pd_bbs_sr_1?ie=UTF8&s=electronics&qid=1240766534&sr=8-1

but it doesn't record hourly info, just current wattage, voltage, etc, and total kWh used since it was plugged in. and no memory - if it loses power, it's gone.

somewhat fancier is the 'watts up', http://cableorganizer.com/electricity-power-meter/
with the better models having memory and even internet connectivity.

fancier yet are some whole-house models like: http://www.bluelineinnovations.com/

hope that helps,

Cramer Silkworth's picture
Joined: 2011-09-30
Reputation: 0

I've been trying to think of a "cheap" option for logging legacy meters
(i.e. those with no inherent logging). My concept was to use a wireless
CCTV network to take "stills" at set time intervals from the meter.
Issues to think about:
- Even a cheap setup with 2 x cameras will cost $200 + then there's the
network cost (a cheap laptop perhaps)
- Processing the stills could be time consuming. However, a clever
person with some scripting knowledge and OCR software could speed things
up. Or, using a junior could render the stills into a useful spreadsheet
format at minimal cost.
- Picture quality - if the cameras use their own lamp it is likely to
glare. This could be overcome with a polarising filter perhaps.
- The range of inputs is limited to those displayed on the meter itself

The reason for investigating this is because calibrated energy models
are becoming more popular on older buildings as a means of identifying
potential energy savings.

Chris Yates's picture
Joined: 2011-10-02
Reputation: 0

Cypress Envirosystems is moving in this direction. They have a wireless
gauge reader that is indeed a camera that reads the needle for you. This
is for pressure gauges, but it seems like it might be adaptable to other
types. Here's their web site:


Mark Nieman, PE, CEM

Mark Nieman's picture
Joined: 2011-09-30
Reputation: 0

I forwarded the electric sub-meter discussion to The Energy Detective.
They produce low-cost data-loggers with wireless displays specifically
for home use and other buildings with one or two circuit panels 200 amps
or less. Here is their reply:

Hi Bill,
In reading the email chain, it does seem that TED with Footprints is
exactly what they are looking for, as it will log energy-usage data
every second. You also have the ability to profile any load (greater
than 1kW), so that you could see WHEN the HVAC ran, HOW LONG it ran, and
WHAT IT COST to run.
We will also be introducing a new model of TED in the next couple of
weeks...TED 5000. This model of TED will have a built-in web server and
a wireless display. We'll be publishing specs/pricing late next week or
beginning of following....so please check for updates.
Thanks very much for your inquiry....please let us know if there are any
specific questions.

Best regards,

William Bishop, EIT, LEED(r) AP

Bishop, Bill's picture
Joined: 2011-09-30
Reputation: 0