New GEM install

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gtallan
Posts: 6
Joined: Sun Feb 01, 2015 7:47 pm

New GEM install

Post by gtallan » Wed Feb 04, 2015 11:46 am

Just received my GEM last week and installed over the weekend, so thought I would post a couple of photos and join the group. I've been monitoring overall home energy use using a z-wave Aeon HEM reporting to a Vera Lite for a while, and it was fascinating enough I decided I needed more detail :-)

At the moment the GEM is reporting direct to SEG, though I also tested having it report to vera - both work but I can't do both simultaneously at present. The "datamine" plugin of vera does do quite nice basic data storage and graphing but not to the level of SEG. I suppose one option might be to report to vera over ethernet, and to SEG or elsewhere via btmon.py using the second serial port. Having said that, looking at all the posts on the Dashbox makes it seem potentially more detailed and easy to use than SEG - it would be really interesting to see a detailed comparison sometime!

For the sake of completeness, here's the results of my efforts over the weekend. I opted to use 1" PVC ENT to carry the CT wires from main panel to GEM, not having any tools to bend EMT in that size. Pretty happy with the install, though I have about 20' extra ENT coiled up to store for the rest of my life...

The CTs for the Aeon monitor are still on the incoming conductors. There's a 5-10% difference in readings between the Aeon and GEM (I assume the GEM is more correct).

Curious if I should do any calibration of the PT? GEM shows voltage as 122-ish, while my inexpensive DVM shows 124-ish.
CT wiring in main panel
CT wiring in main panel
2015-01-31-0573.jpg (810.87 KiB) Viewed 3290 times
Finished GEM install
Finished GEM install
2015-02-04-0602.jpg (501.81 KiB) Viewed 3290 times
ben
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Re: New GEM install

Post by ben » Wed Feb 04, 2015 12:30 pm

gtallan wrote:At the moment the GEM is reporting direct to SEG, though I also tested having it report to vera - both work but I can't do both simultaneously at present. The "datamine" plugin of vera does do quite nice basic data storage and graphing but not to the level of SEG. I suppose one option might be to report to vera over ethernet, and to SEG or elsewhere via btmon.py using the second serial port. Having said that, looking at all the posts on the Dashbox makes it seem potentially more detailed and easy to use than SEG - it would be really interesting to see a detailed comparison sometime!
You may have already looked through, but Tekens thread has some good comparisons (http://brultech.com/home/community/view ... ?f=2&t=929). The thread pretty up to date with all the updates that come out.
gtallan wrote:The CTs for the Aeon monitor are still on the incoming conductors. There's a 5-10% difference in readings between the Aeon and GEM (I assume the GEM is more correct).
Did you have the V1 or V2? It doesn't look like the Aeon V1 (battery powered) was a true power monitor. The V2 (AC line) looks like it is.
gtallan wrote:Curious if I should do any calibration of the PT? GEM shows voltage as 122-ish, while my inexpensive DVM shows 124-ish.
Is your DVM true-RMS and are you checking at the same outlet? If yes to both, then yeah adjust the type a little to make them equal.
Ben
Brultech Research Inc.
E: ben(at)brultech.com
gtallan
Posts: 6
Joined: Sun Feb 01, 2015 7:47 pm

Re: New GEM install

Post by gtallan » Wed Feb 04, 2015 1:55 pm

ben wrote:
gtallan wrote:The CTs for the Aeon monitor are still on the incoming conductors. There's a 5-10% difference in readings between the Aeon and GEM (I assume the GEM is more correct).
Did you have the V1 or V2? It doesn't look like the Aeon V1 (battery powered) was a true power monitor. The V2 (AC line) looks like it is.
The Aeon is the v1 - I know it can't measure true power, it was just an inexpensive way to get started - though just seeing the relative values it supplied was pretty useful, even if not that accurate.
ben wrote:
gtallan wrote:Curious if I should do any calibration of the PT? GEM shows voltage as 122-ish, while my inexpensive DVM shows 124-ish.
Is your DVM true-RMS and are you checking at the same outlet? If yes to both, then yeah adjust the type a little to make them equal.
I was checking the same circuit as the GEM, but on the meter (Metex ME-11) being True RMS - good question! By some miracle I found the manual but it says nothing about it, so perhaps I should assume not. The manual section about serial datalogging to a PC mentions Windows 3.1 and 95, which dates it a bit :-). I can probably borrow something higher-end if I need to.
gtallan
Posts: 6
Joined: Sun Feb 01, 2015 7:47 pm

Re: New GEM install

Post by gtallan » Wed Feb 04, 2015 3:34 pm

ben wrote:You may have already looked through, but Tekens thread has some good comparisons (http://brultech.com/home/community/view ... ?f=2&t=929). The thread pretty up to date with all the updates that come out.
I read it many times, thanks (lots of good background info for the GEM itself), it has loads of detail and pretty clearly shows what a nice product the dashbox is.
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