correct, i see what you mean - so are you saying that this transfer switch is problematic? because it does not switch the neutral? problematic in terms of being compatible with ac300s in split phase set up (with a 240v circuit) i mean
In order to pass local code and inspection your transfer switch must isolate the hot and neutral wires from the main breaker to ensure no back-feed to local grid. I’m not going back and forth with this, if you went with a switch that doesn’t isolate it because you wanted to save on wires that fine with me… but reliance does make an x-series that does this.
Concerning the switch from bonded to non-bounded that is not done by the AC300. When you plug your tester into the the outbound ac ports of your ac300 with no incoming grid you’ll see that its not bonded. When you plug in your AC grid, the pass-though allows your tester to see the bonding of neutral and ground from your main panel… this even happens before the AC input is turned on by the AC300.
The AC output is only interrupted when the AC Grid “Input” is introduced or taken away.
The X-series does switch the neutral. The more common Reliance ProTrans series does not. (See the wiring diagram I posted directly from a Reliance manual above.) I didn’t choose this to save wires, this is how most transfer switches were designed. Reliance still sells these switches so I gather they must still pass some codes.
Yes, that is what I said. From the perspective of the device you have plugged in, it changes from bonded to non-bonded though.
Not if you have a device plugged in directly. AC output remains on in both cases for devices directly plugged in. AC output is turned off only with certain transfer switches. And only when grid power is introduced, not when it is taken away.
Yes, unfortunately I think our transfer switches are problematic because they don’t switch the neutral. There are some reports here and in the Facebook forum that “Winnie” from Bluetti is sending units that “fix” the problem, but I haven’t seen anything confirmed, and I just keep going in circles with support about the issue.
One thing I’ve learned from this is the quality of support for such an expensive product is not up to what I personally would expect. Why did @BLUETTI stop responding to this thread? If our switches will never be compatible, please just say so.
I don’t think I’m going to invest any more money in their products.
So the only thing I can think is that maybe we’re not talking about the same issue… I watched the videos from above from the user who put them on the Google drive on the Grid power causing a alarm when power is returned… I don’t experience this issue and I’m uploading a video showing the same steps he did. Maybe I have one of the newer versions, as I did get my unit in May 2022.
I’ll post the video as soon as it is uploaded.
That video is from me. I asked Winnie about the progress from the issue and she asked me whether the new ac300 she rma and sent me fixed the issue. So I tested new ac300 yesterday and when I restored the grid by plugging in the ac 15a power chord, the ac300 made a pop noise got 008 OCP and shutdown. Now it would not power back up. Someone else had this same issue several months back as we were both testing the same issue with transfer switch. His popped when grid was restored and went down hard needing replacement.
My old ac300 was sent back to bluetti for analysis. That one the ac inverter shuts off with a high voltage alarm. But I could reset the alarm and restart the ac output. This replacement popped. Winnie should be sending me a rma for this to be replaced.
Did you ever try to restore power without the Groove Smart outlet? I have another brand of those smart outlets and they do not provide a very clean disconnect or reconnecting of power.
I also spent the time to install a local disconnect panel for my grid input because I noticed previously that if I didn’t plug in the 15 amp cord into the wall socket fast enough that I would get errors on my AC300. However ever since I installed the disconnect panel I’ve had zero issues turning on/off the power to my AC300 units.
In regards to bonded neutral and all this conversation got me learning more about the function of neutral and why neutral is bonded to ground.
After reading about it I learned;
Neutral is required for a complete circuit so the electrons/power source can be returned. No circuit, electrons don’t flow and cannot drive the load.
Neutral bonded to ground on main panel- for u.s. residential panels NEC code requires it so that when there is a short, the current will flow more predictable and the circuit breaker will sense the short and cut power.
When grid power is restored with the switch connected, the grid neutral must be in play and somehow neutral’s voltage fluctuates or is disturbed and the ac300 senses that and acting like a circuit breaker and cuts power by shutting the ac output/inverter.
Just a thought.
Does anyone know if there is a way to turn off grid pass through so that the grid power is only used to recharge the battery and not use for load powering. Seems running using the inverter all the time might be more stable and less problematic. Even in split phase as knowing which phase is being used by which ac300.
The other difference that I want to point out is that I’m not using the 15amp charging cord. I’m using a L14-30 240v cable to provide 30amps to my two AC300’s. I noticed that the 15 amp cords are non-polarized… which to me is very odd to have on a modern electronic… have any of you confirmed that your getting your hot/neutral on the correct sides of your outlet: Neutral on large pin, hot on small.
I only used the plug. I did notice your video with the 30amp breaker. I think that was you. That you were able to supply and cut power without alarming the ac300.
I already checked with Bluetti support on this, as I have another case open for a similar but different issue. The answer is no… you can not turn off grid pass through and only charge the battery.
That should be an option
I totally agree!.. can you test the polarity of your 15 amp outlet that your using to charge your AC300 and confirm hot and neutral are coming out on the correct prongs…
And you are correct on your research on the what neutrals are used for and why only the main panel is bonded.
I checked the polarity and it is correct. The white neutral connects to the left side wider prong and the black on the right side narrow prong. You had be guessing there for a while because I replaced the outlet not long ago and maybe wired it incorrectly. I also used an outlet tester and the lights showed correctly with no wiring exception.
Also, on my video, I was using a smart wifi outlet to turn the power on and off. Not plug in and out using chord. However with the blown ac300 yesterday, I was using the chord plugging method as the wifi outlet was put away. The other person who blew his ac300, I think used his circuit breaker like you.
Bummer… thanks for that report @ty4602yf. I thought maybe Winnie understood the problem but it doesn’t sound like she does. It would be consistent with my experience with support in that I don’t think they understand the issue.
Do you have a transfer switch plugged into the AC300? Your video is consistent with all of our experiences – the problem happens only when certain transfer switches are plugged into the unit. Other devices work fine.
You can do this by plugging in one of their T500 chargers into the AC300 or B300, and disconnecting the AC300 from the wall. (See post 49 above where I mention this.) It has disadvantages like you are limited to 500W of charging, you can’t set UPS options like PV-priority, it’s loud, etc., but it does avoid the bypass issue.
Since the EP500 has this “online UPS” functionality built-in, it would be nice if they could just add the functionality to the AC300 firmware… it actually would be the simplest solution to the problem.
My transfer switch was not plugged in. I will run another test once my new inlet comes today as I have it unwired at the moment.
I do have a question on that though… with the transfer switch connected for these test, do you have all your loads in your transfer switch turned on?