Power Monitor Products

Open Neutral

Senior Member
A previously mentioned residence has four 200A panelboards. The client friend loves gadgets. Giving he's now paying PSE $500 a month for a supply of electrons err holes [down from $900 thanks to GSPH's], a monitoring system would be met favorably.

I happen to have eight CT's gathering dust.

So I have a choice of finding an existing COTS power monitor with 4 inputs, or building one out of a PLC/microcontroller of some flavor.
Any suggestions of products that monitor 4 channels, and displays current/VA/maybe watts, either on a LCD or a webpage?
 

GeorgeB

ElectroHydraulics engineer (retired)
Location
Greenville SC
Occupation
Retired
A previously mentioned residence has four 200A panelboards. The client friend loves gadgets. Giving he's now paying PSE $500 a month for a supply of electrons err holes [down from $900 thanks to GSPH's], a monitoring system would be met favorably.

I happen to have eight CT's gathering dust.

So I have a choice of finding an existing COTS power monitor with 4 inputs, or building one out of a PLC/microcontroller of some flavor.
Any suggestions of products that monitor 4 channels, and displays current/VA/maybe watts, either on a LCD or a webpage?
First comment is that you'll need 8 inputs assuming panels are 120-0-120. I've done this industrially with ActionPak modules and a Dataq data acquisition unit with an old Windows pc for data storage and display. With that many channels, a Dataq unit using plug-in converter modules will be less expensive. Their display software can do very limited on-the-fly calculation to display VA, but just the currents would probably be all you need. Budget about $2000. You'll need a burden resistor for your CT to get an AC voltage; selection depends on the CT. Look at the 4718 product https://www.dataq.com/products/di-4718b/di-4718b-u.html and eight of the 8B40 https://www.dataq.com/data-acquisition/amplifiers/8b/ modules depending on CT and burden resistor.
 

BBEE

Member
Location
Colorado
Another option for you is eGauge. https://www.egauge.net/ They are cost effective and can easily take 8 ct inputs.
They store all the data on the device and have free access to it through a web page.
I've installed a lot of these, mainly for solar projects, but also for some consumption only monitoring projects.


Sent from my Pixel 2 using Tapatalk
 

gar

Senior Member
191209-2119 EST

Open Neutral:

You need to find out what the customer really wants, and needs. Over the long haul interest in the data won't be maintained. However, as a learning, and study tool a recording monitor can be useful. Monitoring of one phase, or portion of, and supply may be all that is needed.

I have played with the TED system to some extent. See my web sites:
http://beta-a2.com/energy.html
http://beta-a2.com/engry_b.html
Plots P26 thru P30 at http://beta-a2.com/EE-photos.html

All my TED plots are of a time resolution of 1 second.

.
 

Open Neutral

Senior Member
191209-2119 EST

Open Neutral:

You need to find out what the customer really wants, and needs. Over the long haul interest in the data won't be maintained. However, as a learning, and study tool a recording monitor can be useful. Monitoring of one phase, or portion of, and supply may be all that is needed.
The client has reduced his POCO bill from $900 a month to $500 by spending [scientific notation$$] on multiple geosource heat pumps and water heaters. (Also cutting his propane usage.) He's interested in seeing consumption of each as well as the existing split-units. I talked to a support person at TED and it sounds like they have lots of flexibility in the system. There are multiple buildings and the system can be tied together by LAN so it's sounding ideal.

The webserver at Egauge is so out of date I can't even talk to it.
 

Open Neutral

Senior Member
re: TED

I've been having a conversation with an actual engineer there; life is SO much easier talking to a professional. This appears to be a 3rd generation system. Gar's work seems to have been on a predecessor.

The whole product is quite flexible; the CT's connect to a Measurement Transmission Unit (MTU); the thinking is done by an "ECC" with a webserver; you can see realtime results on that, and a cloudbased application can group inputs together and sum them up, monitor peak demand, and far more.

The residential version talks MTU{s} to ECC via power line carrier. (Yitran IT700 PLC System) The industrial model handles 3-ph, and it has Ethernet with a PLC option. They also make a smaller 3-ph unit that they say is popular in the EU and beyond; there are many homes there with 3-ph.

One thing I've learned is the PLC MTUs are approved to be installed inside a panelboard and wired to an existing {nte 40A} breaker. That powers it, gives it voltage/phase angle and PLC injection. As it happens, we'll have an ex-CT box available to install it and the addon 8-port muxs for more CT's.

The PLC and system capacity limits (Each ECC can handle 4 MTU's w/mux for total of 36 circuits) mean a 2nd ECC in the outbuilding. (It's soon to be fed by a 2nd xfmr.) But the cloud app can merge the data.

The client loves the idea.
 

Open Neutral

Senior Member
One followup question. The outbuilding has two 200A main disconnects. The installation will require CT's in the disconnect at the downstream side of one main; AND 0.5" EMT to a panel fed off the other main. (Its CT's will be in the panel.) Will this get the AHJ upset?
 

Open Neutral

Senior Member
Well, the TED engineer told me they'd started out with monitoring the panel main and attempting to profile major loads; they found it unreliable so they created their Spyder to sense individual branches.

Here's an update on the feed upgrade project. On the 11th, a platoon of the EC's workers, and a similar number of Potelco's, the PSE contractor, troops, and PSE Metering, descended on the property. I alas, was on this coast. But I was told/saw imagery that jointly, they:
  1. With a truck crane, put in the pad for the new 100 KVA xfmr.
  2. Pulled the 550 ft primary run from the neighbor's xfmr
  3. Pulled the new 85 ft parallel 350MCM secondary runs to the house.
  4. Swung the new xfmr over to the pad.
  5. Terminated the new runs into the xfmr & new main disconnect.
  6. Removed the old 350MCM to the CT can.
  7. Removed the old 200A interior CT's and mounting base.
  8. Used the old CT can as a jbox for the 3 sets of runs to 200A panelboards. (The new 4th panelboard is 150 ft away; it gets a fused disconnect outdoors next to the main. I wanted it inside as well but lost that battle.)
  9. Pulled the new 300 ft 350MCM from the 37.5 KVA existing xfmr to the outbuilding and terminated it at the meter there.
  10. At the neighbor's, dug out access to the pad, and snaked the HV cable up into the (live) 25 KVA xfmr.
  11. Terminated the cable ends, and when everything was connected, hot-stick connected our new feed to the 2nd bushing on that xfmr.
  12. Phew.
Along the way, PSE Metering pulled one old CT meter, installed a new one for the 600A CT's, and installed a new 320 series direct meter on the barn.

The good news was it had stopped raining a few days before and abstained all day. As Charlie can no doubt relate, this was a welcome break from the month before when the animals were seen lining up 2 by 2.

I was intrigued by several things I (didn't) see. The GC confirmed there was no ground rod driven in under the pad. There's a bundle of bare ground wire emerging from the side of the pad; can't see where it eventually went. I recall PG&E required a driven rod under the pad, and a second one several feet away.

I was also surprised they didn't disconnect the feed to the 25KVA before step 10/11, but nope.
 
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