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UPS's not working on battery power

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Having an extended grid outage today due to a big snowstorm. The cool thing is the Tesla app new the forecast and charged up the Powerwall to 100%.
However...
I have APC UPS devices on my router and TVS. These UPS'S don't get enough power to function when we're on battery. If I unplug the devices from the UPS and plug directly into the wall, everything works!
So I've had to go around my house and disconnect each of the UPS'S.

Does anyone else have this experience? Any insights?
Thanks!!
 
What @zTesla said. ^^^

You probably don't want to read the whole thread on this but:


TLDR: When your batteries fill up to close to 100% and your grid connection is down, your gateway will increase the AC frequency as a way of signaling your inverter to shut off (to avoid generating solar energy that has nowhere to go). By default this AC frequency is out of spec for many home UPS units (they generally want 60 +/- 3Hz, but check the specs for your individual units), so they switch over to batteries. (So it's not that the UPSs "don't get enough power", they're rejecting it because the AC frequency is wrong.)

There should be a FAQ or something about this.

Bruce.
 
What @zTesla said. ^^^

You probably don't want to read the whole thread on this but:


TLDR: When your batteries fill up to close to 100% and your grid connection is down, your gateway will increase the AC frequency as a way of signaling your inverter to shut off (to avoid generating solar energy that has nowhere to go). By default this AC frequency is out of spec for many home UPS units (they generally want 60 +/- 3Hz, but check the specs for your individual units), so they switch over to batteries. (So it's not that the UPSs "don't get enough power", they're rejecting it because the AC frequency is wrong.)

There should be a FAQ or something about this.

Bruce.
I have 50/60 +/- 5Hz UPS's and I still had problems. I called Tesla and they verified I was at 65 Hz when my Powerwalls were at 83%. They said I should expect the higher frequency down to about 80%. They submitted a Tier 2 support ticket to reduce my frequency.
 
What @zTesla said. ^^^

You probably don't want to read the whole thread on this but:


TLDR: When your batteries fill up to close to 100% and your grid connection is down, your gateway will increase the AC frequency as a way of signaling your inverter to shut off (to avoid generating solar energy that has nowhere to go). By default this AC frequency is out of spec for many home UPS units (they generally want 60 +/- 3Hz, but check the specs for your individual units), so they switch over to batteries. (So it's not that the UPSs "don't get enough power", they're rejecting it because the AC frequency is wrong.)

There should be a FAQ or something about this.

Bruce.

You are right, we probably should have a FAQ on this. I have thought about it before, actually, on this topic. While I understand the general issue the same as you explain it here), and have read through the referenced thread in mostly real time when it was active, I dont feel I have a technical enough grasp to write an explanation.

If I wrote something, it would be similar to what you have just posted, maybe with some more tips on recommendations on how to converse with tesla on the issue. Given the somewhat technical nature of many people in this subforum, I hesitate to post something as a FAQ like that, that doesnt have any real technical explanation.
 
I have 50/60 +/- 5Hz UPS's and I still had problems. I called Tesla and they verified I was at 65 Hz when my Powerwalls were at 83%. They said I should expect the higher frequency down to about 80%. They submitted a Tier 2 support ticket to reduce my frequency.
If your UPS accepts 60+/-5Hz then why does it not work with 65Hz from Powerwall? Did you measure the actual frequency?
 
It is possible the GW frequency overshoots 65Hz initially, or varies 64.9-65.1Hz, and the UPSs properly shut down. Also, they may be designed to not revert to line power until the frequency is closer to 60Hz...

FWIW, I believe Tesla should change the default frequency shift in firmware to 62.5Hz, since many electronics, including virtually all desktop computers, have a 63Hz limit. Then there are cheap clocks that rely on phase-synchronous motors, and will run fast while the frequency is raised...
 
It is possible the GW frequency overshoots 65Hz initially, or varies 64.9-65.1Hz, and the UPSs properly shut down. Also, they may be designed to not revert to line power until the frequency is closer to 60Hz...

FWIW, I believe Tesla should change the default frequency shift in firmware to 62.5Hz, since many electronics, including virtually all desktop computers, have a 63Hz limit. Then there are cheap clocks that rely on phase-synchronous motors, and will run fast while the frequency is raised...

65hz is unnecessarily excessive, it screws with so so so many things.
  • LED bulbs will flicker
  • Induction cooktops don't work
  • AFCI/GFCI breakers will trip
  • Anything motorized will run fast (garage door opener, vacuums, furnace blower, etc)
  • Powerline ethernet adapters stop working
  • Home automation systems will fail to communicate
  • Compressors will not start (really bad for refrigerators or freezers)
  • 65hz is way out of spec for ATX power supplies
  • etc etc etc
Beyond the challenge of physically getting one it's one of my biggest complaints with Tesla's Powerwall offering at this point.
 
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65hz is unnecessarily excessive, it screws with so so so many things.
  • LED bulbs will flicker
  • Induction cooktops don't work
  • AFCI/GFCI breakers will trip
  • Anything motorized will run fast (garage door opener, vacuums, furnace blower, etc)
  • Powerline ethernet adapters stop working
  • Home automation systems will fail to communicate
  • Compressors will not start (really bad for refrigerators or freezers)
  • 65hz is way out of spec for ATX power supplies
  • etc etc etc
Beyond the challenge of physically getting one it's one of my biggest complaints with Tesla's Powerwall offering at this point.
What's strange is my LEDs will flicker when the solar is putting out on backup but my LEDs were not flickering (my panels were covered with snow). I initially didn't attribute the problem to the frequency shift since my LEDs weren't flickering and I was at 83% when I called Tesla.

My clocks run too fast when running off Powerwalls and too slow when running off my generator....

The ironic thing is I got the UPSs for the switchover when the power goes out. Before I had Powerwalls everything would just reboot once power was restored. The quick switchover when I got Powerwalls caused problems with my modem/router and my DVR system. They would just freeze up and become unresponsive. I wish there was a better solution than UPSs for the switchover since they are overkill and the batteries will need to be replaced eventually.
 
I don't have a meter that I would trust to a decimal place. I suspect there is some tolerance on the tolerance, both on the UPS and Tesla. Even if there wasn't, Tesla could be putting out 65.4 Hz and call it 65 Hz.

Powerwall really should not put out 65Hz. But I had been under the impression that 65Hz UPS was a good workaround for the Powerwall frequency issue. Apparently not so much.
 
I removed the UPS after my Powerwalls were installed. No problems.
Problems are not likely to be revealed in the short term, except the fast clocks issue already mentioned. Your computers and other electronics that run from line power may or may not survive the switchover, depending on their sensitivity (my microwave and wall oven both require resets).

However, you may incur additional wear on electronics from excessive heat generated at higher than specified frequencies. Also, other motors such as refrigerators and furnace blowers may wear out more quickly if running for a long time at the higher frequencies.
 
Call Tesla and request they lower the grid-out frequency max to 62 (or 62.5). This fixed it for my APC UPSs
Excellent! Thanks for the detailed and informative response. I'll dig in to those threads and then call Powerwall support.
FYI - we've been without power for over 30 hrs now due the snowstorm in VA/DC. The Powerwalls anticipated the storm, boosted the charge to 100% and that got us through the first day but the panels are still covered by snow, so we had to vacate to find heat, power and internet!! Again, appreciate all the input and discussion.
 
Excellent! Thanks for the detailed and informative response. I'll dig in to those threads and then call Powerwall support.
FYI - we've been without power for over 30 hrs now due the snowstorm in VA/DC. The Powerwalls anticipated the storm, boosted the charge to 100% and that got us through the first day but the panels are still covered by snow, so we had to vacate to find heat, power and internet!! Again, appreciate all the input and discussion.

The TL ; DR version of the very long thread linked to, is that you can call tesla to request the frequency be lowered. What they will lower it to depends on what your equipment is (solar). You generally have to give them symptoms that you are experiencing, as well.

So, you would want to call tesla tier 1 powerall support, and say something like:

===========================
Hi, I am having issues when running on powerwall power with my APC UPS devices not operating properly, my LED lights flickering, and my Microwave making strange noises while running on battery / powerwall power. After investigating the cause, I found this is related to the powerwall frequency being 65Hz, and that this can be lowered to a number that my equipment supports. I would like to request this frequency be lowered to a number that my equipment supports to prevent these errors."

(or something close to that).
==========================

They will have to escalate it to "Tier 2" unless something has changed, as they need to review what your inverter supports as a shutoff, etc, and if tesla did not do your solar or powerwall install, you may have to provide some more information about solar inverter model, etc.

They will take "some time" and since they are aware of this issue, should lower it for you, to something like 62hz or 62.5hz, which should correct this for you.

On a side note, wishing you the best with your situation in the weather out there.
 
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Excellent! Thanks for the detailed and informative response. I'll dig in to those threads and then call Powerwall support.
FYI - we've been without power for over 30 hrs now due the snowstorm in VA/DC. The Powerwalls anticipated the storm, boosted the charge to 100% and that got us through the first day but the panels are still covered by snow, so we had to vacate to find heat, power and internet!! Again, appreciate all the input and discussion.

Great example of why you should have a backup generator even with a home battery.
 
The increase to 65 Hz (or higher than 62 Hz) is necessary to ensure control and shutdown of older inverters when the battery is full and the grid is down. That is when the Powerwall Gateway raised the frequency to terminate solar production. My inverters are shut off at 61 Hz or so and Tesla set my TEG to rise to a max of 62 Hz. But I understand older inverters may need to go higher. FWIW, this has worked flawlessly for us during tests and in real power failures.
 
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That is not a problem until you record on tivo that would shut off even a fractional second, or the modem and wi-fi could drop off. Reboot takes time. ;) :)
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!! ;)