Recent content by wwhitney

Can I replace my whole PV or PV/ESS system with a new one that exports up to 1kW more than my existing system? Or am I stuck with (uncontrolled PV inverters that can export up to 1 kW more than the existing system) plus (controlled PV inverters that never export)? Can the Backup Gateway...

Seems not directly related to me, the CTs just have to placed to see the appropriate current for the system to be able to offset the desired load. While the above is true, it's a side effect of the resistance between the CT location and the ESS. In that if the CT sees net current to the grid...

Yes, and this happens seamlessly. In that the system is likely not measuring the voltage at the left where it's 240V, and if it is doesn't use that as part of its control algorithm; the ESS just sees that its terminal voltage rises as it tries to push out more current, and the ESS always...

You seem industrious enough to find the California state law section that codifies what I said. Hand them a copy and tell them they are full of it. Cheers, Wayne

I'm still around, I'm just not spending much time browsing all the new threads to find the ones that have interesting electrical questions. Feel free to tag me on such threads to get my attention. I expect you know this and are speaking tongue-in-cheek, but your contractor has an affirmative...

Installation of exposed electrical cable (be it on the utility side of the service disconnect, or the house side) is allowed under the NEC unless it is "exposed to physical damage". Much of the US (most of the East, I think) considers an install like that not to be "exposed to physical damage."...

I get 124 kWh, using 1 gallon of LPG has a heat content of 84,950 BTUs, and 1 kWh = 3412 BTUs. https://en.wikipedia.org/wiki/Miles_per_gallon_gasoline_equivalent But that's a theoretical number, you could only make that conversion if you had a fictious 100% efficient LPG generator. If your...

If you actually have Single Wire Earth Return, that's pretty rare these days. Hopefully the distribution in your area will be updated some day. Cheers, Wayne

OK, I agree that the sentence I wrote "There is only one phase present in this configuration, and any two voltages you can measure are in phase with each other" is not standard usage. Rather I should have said "any two voltages you can measure are scalar multiples of each other." Generally "in...

I will agree that you would call the two waveforms 180 degrees out of phase, or negative, or something equivalent. But my point is that those two waveforms only form one "phase". Otherwise, you'd never have single phase, as if I give you two wires A and B, the voltage waveforms A-B and B-A...

Not sure about this part, it varies, but I would be surprised if it is as low as 700 VAC on the primary side of the first transformer upstream of your house. I would think 2.4 kV would be a more likely minimum. But my familiarity with this part of the utility network is limited. Basically...

No, that's not correct. A phase is a collection of possible voltage waveforms that are scalar multiples of each other. If I give you a 2-wire supply, with an autotransformer (a coil with multiple taps along its length) you can get as many different voltage waveforms as you like, but they will...

In the first case, 3 wires line side and load side. In the second case, 3 wires line side and 4 wires load side. Cheers, Wayne

To expand on this, both panels U and W in the diagram should be so labeled. And they should both be outside as specified. If for some reason U was not installed, and W is outside, and the "(E) Distribution Panel Left" is inside as I understand it to be, that would be 230.72(A) violation. On...

Is the multi-line diagram you posted accurate? https://teslamotorsclub.com/tmc/threads/installation-is-starting-8-pw-and-12-solar-panels.287981/#post-7255056 If not, please post a corrected mutli-line diagram in this thread. Also, please identify for each piece of equipment on the diagram...