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UPS's not working on battery power
- Thread starter KDeanCville
- Start date
Time to buy another UPS. I have dedicated UPSes for my media and network racks. No way I am going through a power outage without TV, internet, and Tivo. That would be uncivilized!!
I have 5 in my home for all of my various and sundry electronics.
Yes, I have a problem.
I think you already solved the problem - just ditch the UPSes. Why keep them around? It seems duplicative, unless you need them for something critical like medical reasons.
I've experienced several power failures with the Powerwalls, and none of my electronics - computers, routers, even my finicky microwave time display - even blinked an eye.
I've experienced several power failures with the Powerwalls, and none of my electronics - computers, routers, even my finicky microwave time display - even blinked an eye.
This is not always the case depending on your system specs, configuration, Powerwall state of charge, current PV production, and the type of outage. In some, maybe most, cases the transition is quick enough for sensitive electronics. I've personally experienced outages that take multiple seconds for the Powerwall to take over which is why I keep my equipment on UPSes. YMMV.
This will not always be the case, depending on a bunch of various factors. Thats why a lot of us still have UPS's on things we dont want to have a potential blip if there is a power outage. You really only need a potential few seconds as most, but the experience you explain is the desired outcome, but it will not always be that way.
A TL ; DR version of one of those conditions is, it depends on whether your PV system (or powerwalls) are actively covering your entire home load at the time of any power disruption. Sticking with the " TL ; DR" I said, if your powerwalls are full and on standby mode, and your PV is not covering your entire home load at the time, if you have a power outage, you will likely experience a power "blip" while the powerwall switches on and picks up.
That may or may not matter to you, but if (for example) you have expensive electrical equipment, or home NAS devices, DVRs, etc you dont want to experience that potential blip, you need a UPS to cover that possibility.
There is a long thread on we had on this discussion if you want to read more about this forums thoughts / experiences on it. Let me know if you want me to link it.
RKCRLR
Active Member
As mentioned, it depends on your case. I got UPSs specifically because of the problems I was having with the fast (but not instantaneous) switchover to the Powerwalls that I didn't have before the Powerwalls.
I have lost power at all times - day, night, weekday, weekend - of varying durations from 5 minutes to 24+ hours, with the PWs in various states of charge from 100% down to 60%. I have never, EVER, noticed any of my electronics being affected by the failover. Ever. Not even the microwave clock that resets to 12:00 if you sneeze too loudly.
Is there a configuration that could possibly cause enough of a disruption to reset my various electronics? Possibly, but I haven't encountered one yet.
I guess my point for the other readers of this thread is - it's one thing to be speculating that this is a problem, and another thing to actually be experiencing it as a problem. I would wait for the problem to manifest itself before spending money (and adding complexity) trying to fix it.
Its not speculation, it happens, under various circumstances. Its actually more surprising that you havent experienced it at all.
How come power changeover was not seamless during power outage blip?
Well, this is interesting. Am sitting at my computer and the screen glitches. I get a text from my Ting line monitoring device that power has gone out, and then was restored "quickly". Looks like a transformer blew in the area, but we had a quick restore. Others are not without power. But...
teslamotorsclub.com
It's very cool that you've never experienced this momentary disruption during a change-over. (I mean that genuinely.)
But just because you've never seen it doesn't make it imaginary or unlikely. A number of people (I would say a significant number of people, and I'm most definitely one of them) have experienced cut-over times long enough to cause servers to reboot, etc. There's a real risk of this happening. It's probably a good idea for people who care to test their home electrical setups by going off-grid under different circumstances and seeing what happens. In other words, do some due diligence and check, rather than waiting for an actual outage to find out.
I'd guess that most people who have significant IT setups or sensitive electronics equipment at home already have UPSs, so for those folks, there's no additional expense or complexity involved. All that's really needed is asking Tesla to cap the maximum frequency.
Bruce.
jlv1
Twice as much fun
A transformer next door just blew this morning and the grid went out. And then all the UPS beeping started. I checked, and our Powerwalls are outputting 65Hz.
The thing is, I called Tesla almost exactly a year ago and had them lower this to 62Hz. So sometime since then they reset the value back to the default. Now I have to call them again.
The thing is, I called Tesla almost exactly a year ago and had them lower this to 62Hz. So sometime since then they reset the value back to the default. Now I have to call them again.
jlv1
Twice as much fun
At what battery percentage does the Powerwall go back to 60Hz? I'm at 87% and we're still running at 65Hz. We're getting prime sun right now on the few PV panels that aren't covered in snow; I suspect we'd be generating nearly as much as we're using right now. But the panels that get better sun in the afternoon are still covered by a foot of snow, so by the time we get down to 80% we'll have no ability to generate for the rest of the day.
From the various posts here on that topic (what percentage does the powerwall allow the solar to come back on, by lowering the frequency to 60Hz), I have not seen a consensus on this. Some have reported it came back on at 93 ish%, and some like yourself have reported their powerwalls in the 85% range and still on battery.
Hopefully it comes on soon for you.
aesculus
Still Trying to Figure This All Out
I am wondering if there is some learning algorithm on when and how much the frequency change is and when it starts. The purpose is to reduce (eliminate) the solar inverter providing more energy than the home/Powerwall's can consume at a given time. This is going to be somewhat different depending on how many inverters you have, what their output could be and of course the state of your current loads and the Powerwall SoC.
I for example have 3 separate systems and two of them are Fronius and one Delta. How each responds to frequency shifts is a mystery to me. I am not sure that they scale the output based on the frequency or are binary, just turning on/off based on a frequency threshold. Plus each may have a very distinct profile where one unit may output at say 60.5 Hz and another might not. I understand when coming up from a lower SoC (like 80%) the Tesla system will incrementally increase the frequency until it achieves the goal of limiting the returned energy from the solar systems. This could be highly variable or at least a spectrum of results based on a set of frequencies. But what it does when it finds itself in an immediate situation (full Powerwalls and no grid) may be different. Perhaps it just goes for the maximum it's set at and then waits for the Powerwalls to drain to some value before it tries to bring anything back on.
So a really sophisticated system would learn through some sort of limited AI what type of response would occur at a given frequency. Whether Tesla is there yet in any form is unknown to me. And I have had so few outages that required this sort of treatment I cannot contribute to the conversation with real world observations.
I for example have 3 separate systems and two of them are Fronius and one Delta. How each responds to frequency shifts is a mystery to me. I am not sure that they scale the output based on the frequency or are binary, just turning on/off based on a frequency threshold. Plus each may have a very distinct profile where one unit may output at say 60.5 Hz and another might not. I understand when coming up from a lower SoC (like 80%) the Tesla system will incrementally increase the frequency until it achieves the goal of limiting the returned energy from the solar systems. This could be highly variable or at least a spectrum of results based on a set of frequencies. But what it does when it finds itself in an immediate situation (full Powerwalls and no grid) may be different. Perhaps it just goes for the maximum it's set at and then waits for the Powerwalls to drain to some value before it tries to bring anything back on.
So a really sophisticated system would learn through some sort of limited AI what type of response would occur at a given frequency. Whether Tesla is there yet in any form is unknown to me. And I have had so few outages that required this sort of treatment I cannot contribute to the conversation with real world observations.
My experience has been in the 96% or so range the frequency stops dropping back to 60 Hz. I have a PW2 with a standalone TEG panel.
I wonder if it also is a function of time. Many changes (changes to Self-Power state, enabling/disabling StormWatch, etc.)on the TEG seem to work on 300 sec or so increments. The one exception is takeover on grid failure, which is a 1/60 of a second or so.
For me, its around 93-95% that my solar will come back on, in the above situation (grid out, PW full or > 95% and providing power to the home). In the scenario I described in the previous sentence, if I drain the powerwalls down past 95% the frequency will drop, and my solar will come back on, at least from my tests.
I also have 2 PW 2s with a stand alone Tesla energy gateway (TEG), connected to a previously installed PV system from 2015 with ABB inverters that do not curtail, only "on and off".
With all the above being said, I have still seen others post here that their PV has not restarted and they are in the 80% range, just like @jlv1 reports, so I dont know what the parameters are around this.
I actually tested this last year and found that my frequency went from 62hz at 100%-95.4% SoC, to 61hz at 94.3%, and 60hz at 93.4%. YMMV.
@jlv1 , did your solar ever come back on, and if so, do you know around percentage your powerwalls were?
I suspect that the behavior has changed in the more recent Powerwall firmware releases. We had a 2 hour loss of utility power on December 6, and my wife noticed a beeping noise from the kitchen range. I was at work, but she was able to find our Poniie Power Monitor, and send me a few screen shots. Comparing the frequency with the PW state of charge as reported in data downloaded from the version 4.4 app shows 65Hz at 86%, 64Hz at 83%, 63Hz at 82%, and 61Hz at 81%. We didn't check again until the utility power came back on. The solar started generating at 79-80%, but weather conditions were quite poor, and the onset of generation may have been related to weather rather than PW charge state.
I don't have the exact data from an outage last summer, but IIRC it cycled solar generation on/off at the low 90% range.
I don't have the exact data from an outage last summer, but IIRC it cycled solar generation on/off at the low 90% range.
RKCRLR
Active Member
I called tesla when my solar wasn't coming back on until well below 95% charge. Tesla told me not to expect solar to start charging again until the Powerwalls got below 90%.
I called Tesla when my UPSs (+/- 5 Hz tolerance) were in backup mode. My Powerwalls were it 83% at the time. Tesla told me not to expect 60 Hz until the Powerwalls get down to 80%.
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