power metering equipment and software - Page 1
Forum section: electronics / general

author: WReed
author_rank: Newbie
timestamp: December 13, 2022, 02:47:30 pm
content: Hi Folks,My wife works on a farm with one electric utility main line coming in to one meter for the whole farm.There are several buildings on the farm ~ including two barns, an office, several houses, a shop, farm store and four big wells.The farm would like to monitor power consumption at each building and well's main panel, and optimally, have all that information sent over WiFi to show power use in real time, and send data to a master file. Most of the buildings have pretty good WiFi coverage.The goal is to help people on the farm see where they can lower their energy use.Looking online, I have found large, industrial scale solutions, and some DIY homebrew solutions, but nothing in the middle ground that is simple and at modest cost,.Can anybody point my toward possible solutions?Thanks and good health, Weogo

author: AlbertL
author_rank: Regular Contributor
timestamp: December 13, 2022, 09:40:16 pm
content: There should be some good options available for your application. One question about the distribution topology: do the circuits feeding the various buildings all come together at one central distribution point, or does the line from the meter extend around the property with drops for each building?

author: Gregg
author_rank: Super Contributor
timestamp: December 13, 2022, 10:46:53 pm
content: Search for Emon Dmon; they make revenue grade sub metering systems.

author: Geoff-AU
author_rank: Frequent Contributor
timestamp: December 14, 2022, 04:03:29 am
content: iotawatt?

author: AlbertL
author_rank: Regular Contributor
timestamp: December 15, 2022, 04:48:57 pm
content: If all of the circuits originate from a central distribution point, eGauge meters are another option. Different models can read either 15 or 30 individual lines (current transformers). Seehttps://www.egauge.net/

author: jonpaul
author_rank: Super Contributor
timestamp: December 16, 2022, 11:27:30 am
content: Type and install of current transformers (CT) is an issue.Clamp on are easier, but not accurate and not availabilie for all energy meters.Toroïdal C T are accurate but requires electrician to wire permanentlySome meters have remote monitoring via wifi or wired connections.Beware the Chinese meters that require internet registration. They will harvest your information and use for their purposes. Also the Chinese have a bad habit of bricking your device.Jon

author: Hawaka
author_rank: Regular Contributor
timestamp: December 16, 2022, 11:58:25 am
content: Check out the ABB CMS system. They have open core and solide core current sensors and good accuracy (~1%).I personnaly never used it, but if I would go for a metering device I would probably get that one. It’s a bit pricey, probably around 2k for a full system, but for that accuracy I think it’s quite good.Also precision is what you want for such a system, as you need to detect small constant load or short large ones.

author: WReed
author_rank: Newbie
timestamp: December 17, 2022, 12:46:14 am
content: Hi Albert,Good question about circuit origins - am awaiting an answer from facilities manager.I'm pretty sure it is a mix of some direct-to-building, and some sub-panels off other buildings.I also asked whether the mains supply is single-phase or three phase, andwhat size the first, main breaker is.EGauge is looking pretty good for part of the solution.Gregg, thanks for adding Emon Dmon, a Honeywell product.Geoff-AU IotaWatt is in the running for some more localized metering - within a single building.JonPaul, thanks for the sensor information and China warning.Hawaka, ABB CMS looks good as a smaller solution, appears to max out at 80 amps.Lots of great information here!Some other options from a post on another website:https://sentinelpowerinc.com/Veris/Veris_Modbus_E50SeriesPowerEnergyMeter_SingleCircuit.htmlhttps://www.emporiaenergy.com/https://www.shelly.cloud/en/products/shop/em-120aESP Home Assistanthttps://youtu.be/n2XZzciz0s4open source, local information storagehttps://circuitsetup.us/product/split-single-phase-real-time-whole-house-energy-meter-kit-programmed-esp32-2-cts-abs-box/?v=7516fd43adaaI was able to find someone who does this for a living andhe's asking more questions than I would have considered!Thanks and good health, Weogo

author: Hawaka
author_rank: Regular Contributor
timestamp: December 17, 2022, 06:57:18 pm
content: Quote from: WReed on December 17, 2022, 12:46:14 amThat's true only for the open core design. The close core goes up to 160A. Check out this brochure:https://search.abb.com/library/Download.aspx?DocumentID=2CCC481003C0201&LanguageCode=en&DocumentPartId=&Action=LaunchIf you have to measure such high current I would definitively go for a commercial product btw.

author: jonpaul
author_rank: Super Contributor
timestamp: December 18, 2022, 12:46:54 am
content: For your safety, fire hazard and insurance coverage this may not be a DIY project.At these power levels the install of V and I sensors must be done by a licensed electrician unless clamp on CT used outside of the mains util entry.If the mains panel is opened, the utility company may need to be informed.Bon chance,Jon

author: WReed
author_rank: Newbie
timestamp: December 20, 2022, 02:03:27 pm
content: Hi Folks,Thanks for the additional information.Any significant work in electrical panels will be by a competent electrician.This is a non-profit teaching farm and my guess is progress will be slow and they'll eventually get there.Thanks and good health, Weogo