Three Phase with Windmill


As a disclaimer, I am very green with all things IotaWatt at this point. I read as much as I can but still feel perplexed.

Pertinent Details:
US Based
3 Phase
1 Main , 3 Sub panels
1 Wind Turbine
Iotawatt 5, using derived phase for my measurements

I currently as trying to configure the three phase CT’s but am running into a snag and unsure if it has to do with my turbine or if it is not connected to my main panel. I am told it has an interconnected WECS (unsure what that means).

Taking a step back though, I still do not believe I have my three phase configured correctly. The first clue was that my data graph is showing 2 positive power legs, and 1 negative. The negative reading leg is the confusing one. Even more odd is that it seems to mirror to some level the other 2 legs, but not exactly.

The three sub panels I have are for extra breakers inside, a garage/cooler, and additionally and most importantly, the wind turbine shed. How it is all connected is still over my head at this point, but its the main reason I began looking into a monitoring device.

Secondary disclaimer, the property that I purchased had a turbine installed but little to no documentation.

I am waiting on more CT’s to monitor that particular breaker and if it has any type of reverse power. However, I recently needed to clean up my panel box and shut the main down and had no reading coming from that during a very windy day. If anything was going to back feed that was the day for it to happen.

I’ve read a bunch of forum posts up to this point and a lot of times I see a solar panel showing a positive figure on the power chart and the source as a negative. Is this correct?

Pardon my confusion and my disjointed post, any help is appreciated!

Also, The CT’s are indeed pointing the correct direction. Towards the breakers as I am to understand.


High res pictures of the panels would be good to have in this thread for reference.

The wind turbine is probably single phase. It could be connected to a single phase at 120V or to two phases at 208V. The single-phase 120V scenario would explain one of your mains being negative (back feeding) while the other two are positive.

Typically, a home wind turbine would have a generator that synchronizes to the grid frequency. Like a PV inverter, it will shut down when the grid drops both because it doesn’t have anything to sync to and because of the danger to line crews if local generation energizes an otherwise dead transmission line. So that it doesn’t do anything when you shut down your mains is probably normal.

My advice would be to start with the derived reference setup procedure in the docs. I assume you are using derived. You should either shut down the wind feed or wait for a time when there is no wind.

Once you have that working OK and can reconcile it with your meter, you can determine the phase assignment for each breaker by its position in the panel.

Sorry for the delay! Thanksgiving and whatnot.

So the first image is of some type of surge protector I believe. Not 100% sure about it, but that’s my educated guess.

The second image is of the setup in my wind turbine’s shed, with the third image being of the breaker descriptions. I had a good bit of snow so it wasn’t easy to get out there and take a look inside of the panel, with the cover off, but it’s better than nothing at this point - I will work on snagging a shot of that in the short future. I don’t know if you are able to see it or not on that layout shot, but the top right corner of the meter says “Grid —>”

The last is the main panel in my building. I have a touch more cleaning up of the wires to do still but its almost there. I wasn’t going to be able to fit ANY CT’s in it the way it was prior.

I believe you are accurate in the assumption that the inverter drops when the grid does. I do specifically recall a conversation where I was told if the shed does not have power, power cannot be generated.

Lastly, in regards to the setup procedure, I did follow that to the best of my ability, and you are also correct in my use of derived reference. I would like to use the actual if possible, especially if one of my legs is back flow. I feel like that could throw a wrench in a derived method.

I need to get another shot of the inside door of my panel but had a diagram that appears to have the rails that the breakers snap into in a sort of “S” configuration. There are black squares that go in a pattern (for lack of better description at this point) of A B C B A B C B A … and so on. Is this demonstrating where each of the legs are the primary phase?

Hope this clears up a little and creates less questions than get answered!


I agree that is a surge protector.

I think it’s likely that your service entrance goes to this turbine shed. The main there is your grid connection. The WECS is the “Wind Energy Connection System” where the turbine power is connected and what I think is a 70A three-phase breaker that probably feeds your house.

If those assumptions turn out to be correct, it would make sense to use an IoTaWatt in the turbine shed to measure your mains, wind production, the mains to your house and possibly whatever the three 120V breakers lead to (probably lights and service plugs in the shed).

If you want to further break down your house usage, a second IoTaWatt would be advised.

The turbine shed has an inverter on the right that led me to an owner’s manual for the BWC Excel Wind Turbine. I believe you have the three phase version PSII126208 with 208V single phase output feeding two of your three phases. There is also a display on the front of the inverter where you can read out a lot of operational metrics and control the operation of the turbine. For example it’s possible that your unit is stopped for some reason and you may need to reset it from that display. The manual explains more.

This is worth the price of admission! The two contacts I have had as well as my utility company have been unhelpful on this beyond belief. Thank you for at least getting me to a manual, I should have googled that name on it, but the only other reference material I was given was 2 pages total.

I do know about needing to reset the windmill if it is free spinning as that indicates no resistance and therefore no power generation.

If I don’t have wifi near the shed, is it possible to have a unit out there? I obviously can’t have it push data to InfluxDB Im sure, but could I use its local wifi network to see the information? Additionally, I saw the reference to the 70A dedicated breaker. I do have that in the main building. It’s the bottom right triple pole breaker.

Apologies for my assumptions, but at this point I am still wrapping my head around it all. Am I correct in understanding that according to your prior post, I have 3 legs for my 3 phase, but 2 are run directly from the street service at the brewery, and the third originates at the windmill and then is tracked to the main?

I have two larger conduits that enter the main panel in my business. One is exclusively the 3 main legs and the other is the 3 legs that connect to the aforementioned 70A breaker. I have a picture attached that shows the exterior of the building, so you see the meter placement as well as where the other lines are coming in. I need to verify, but I think that if I cut the 70amp breaker inside the main building it will also cut power at the windmill. This is opposite to your thought on directional flow. Additionally, we use way more than a 70amp breaker would support on site. The main service is 200 amp, and I need to either get a secondary service or increase to 400 amp. That is neither here nor there at this point though! Also, and while it is POSSIBLE, the windmill was installed after the building was built, so I think it probably had its service run from the building – at least is my presumption.

I plan on adding the CT’s on the 70a circuit and seeing what type of readings I get. I have a half guess that it would only be the usage from the shed, so whatever power is required to run the windmill itself. Over the next couple of days I hope to get to the shed and take off the cover to see what I am dealing with.

Also, I am planning on double checking all of my main CT’s to ensure I have proper configuration.

Should one of the 3 legs at the main panel in the building (not shed) actually be a supply from the windmill, will that indeed throw my numbers off? Or is it still possible to get accurate figures, at least as far as at my main building? I’m not opposed to a second, or possible even third unit, because at this point I am constantly questioning some of the equipment installations and that is what led me to iotawatt to begin with!

Thank you again for the assistance so far!


Forgot to add those photos before, and also I have included that “A B C B A B C” diagram I was mentioning before

Since my last post I did a more thorough read of the windmill and inverter manual. I now believe one of the 70A breakers is the feed in from the inverter. I could not make out much detail in the 200A panel but if you saw a 70A breaker at the bottom of the panel, that is probably feeding the windmill panel through the 70A breaker at the top right. The 30A breaker is probably connected to the surge suppressor, but in any event should be revealed with a picture of the insides.

You can run an IoTaWatt without internet or even WiFi, but you can’t communicate with it without WiFi. You can put an inexpensive WiFi router out there and connect to it with a mobile device when you want to look at the data, or you can figure out how to extend your WiFi out there. Ubiquiti has a number of products with directional antennas that can extend over longer distances. On the other hand, it may be moot if the 70A breaker feeds to your main panel, you will be able to measure wind production from there.

Still not clear about your service. The windmill panel says Square D QOC16US which is a split-phase panel. It may be that you have a three phase panel with a split-phase cover, but as far as I can see, there is no need for a three-phase panel there. The windmill inverter outputs 240V or 208V single-phase.

Your main panel looks to be three-phase at first glance, and the picture is low res so I can’t see any detail. It looks like the lower right is a three pole breaker, so that supports three-phase, but I can’t see any other three-phase in the panel. The main has three cables, but they are color coded White, Red and Black. That looks more like split-phase to me. Three-phase would be Black, Red, Blue. Do you know for sure that your higher voltage is 208V rather than 240V? Your previous observation that you had two positive legs and one negative also suggests it may be split-phase. Can you show the full description of the panel that is usually on the inside of the cover door?

EDIT: can you show a detail picture of the outside meter?