quarterly-hour is no longer supported I guess cause I could not use it anymore.
Features Upgrades of IAMMETER (Home assistant integration)
Looks like a nice piece of equipment, but the picture for the single-phase version shows only one clamp-on Amp sensor. Obviously there are two legs in a normal residential panel. Would I need two of these?
No need for two clamps for single phase. What comes through a phase conductor must go back throough neutral, so itâs no need to measure both, since they will be always equal (unless youâd have a major fault in your system and some of the current would go directly into the groundâŚ)
Iâm still not clear how this would work. If you put the clamp on the neutral, thatâs bonded to ground inside the main service panel. Iâve seen other âwhole houseâ energy monitors which use two clamps, one on each hot wire. What am I misunderstanding?
The CT clamp of one phase meter is used to clamp on the live wire. It is enough for one phase grid system.
Some products have two CT clamps, because it is designed for the âsingle-phase three-wire systemâ.
This is the introduction of âsingle-phase three-wire systemâ.
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Exactly. What i wrote above is for single phase, which means one phase ans neutral. For this setup itâs enough to measure voltage between L an N and current through L. Then power is UIcos(fi).
If you meant âamerican styleâ with two phases, or Three-phase system then yes, you need one clamp for each LIVE wire and itâs still no need for clamp on neutral. Why?
- if you have 1-phase system current goes through live and same current goes back through neutral. So no need to measure twice.
- In a multi-phase system current goes in one way through one of phases, but it can go BACK via neutral OR another phase. In a latter case you need to measure this ânegativeâ current on this return phase, in order to know that you must take higher voltage in your power calculation(two phase voltage).
I hope i wrote correctly, since english is not my native languageâŚcorrect me, if iâm wrong. I live in Slovenia, so iâd need version with 3 clamps for my house. Iâm still thinking , since itâs not that cheapâŚ
What iammeter posted is my understanding of how North American home wiring works. The distribution system provides three phases, but individual homes only use one phase, through a center-tap transformer. From there, two hot wires provide 120V to each âlegâ on the panel, and connecting between them (using a double-pole breaker) provides 240V. But itâs still all on the same phase, as viewed from the power distribution system.
So, this âone phaseâ solution may work elsewhere, but itâs not going to work in North America.
I found a diagram which shows whatâs going on pretty well:
Correct (for North America), there are two Hot lines L1 and L2 along with neutral. L1 and L2 are 180 degrees different. Youâll need two CT clamps. As an example, (mentioned in the second post), Aeotecâs Home Energy Meter Gen5 provides two 200A clamps for North American applications.
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Thank you! I had to ponder that one a bit. AC always takes me a while to wrap my mind around.
But I now see how the two voltages on L1 and L2 are equal but opposite, meaning they have to be 180 degrees out of phase with each other, even though theyâre in phase with only one of the three lines on the grid (which, of course, are 120 degrees apart.)
So, looking at it from the grid, a typical N. American home uses only one phase. Looking at it from a load in the home, there are technically two phases, but we donât call them that because that would anger the lineman (I made that mistake only once. It was almost as bad as the time I called the pole he just climbed a âtelephone poleâ instead of utility pole!)
Yes, if you met the âsingle-phase three-wire systemâ that most North American countries used, you need to use two single-phase wifi energy meter(WEM3080).
Or use a three-phase meter that also supports split phase usage(WEM3080T) .
Thank you for clarifying that. North America is a pretty big market. You might want to mention this somewhere on your web site. Or develop a two-leg, one-phase product.
I believe all three North American countries use this system, not âmost.â Unless you count the tiny French islands of Saint-Pierre et Miquelon; I think they use the European system, but theyâre not really a North American Country. But I digress.
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I just got WEM3080T, installed it, and it works. Setiing up was really easy. Only âhard jobâ was finding correct phase order - since wires go into official current meter i couldnât figure it that way, so i just connected one phase, found correct CT ⌠etcâŚ
BUT, i have a question already: is it possible to integrate iammeter into brand new âenergyâ lovelace board? It seems not, since i have no option of choosing iammeter there⌠It seems that entitites from iammeter should be any sort of âenergyâ ones⌠but they are simple sensors. In energy lovelace i can select only energy sensors from my Mitsubishi air conditioner.
Any suggestions?
Hi ,
If your question is how to add the sensor entity of WEM3080T when you want to use the new "home energy management " component.
Please refer to this Home Assistant Energy Integration - Community - IAMMETER
it seems difficulty to merge new feature of integration into HA since last year.
we have to use a compromised method to support WEM3080T in the new âhome energy managementâ component now.
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Yes, that is what i meant. Thanks for your answer, i found that topic and succesfully integrated iammeter into energy.
However, i found out pretty soon that this component is not exactly for my case, since i donât have any energy production, only consumption, while energy component is clearly made for those who have any kind of energy production (solar panels, wind⌠anything).
So i rather made a classic lovelace with gauges and info i need. Itâs just for hobby monitoring anywayâŚ
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