Powerwall 2 + UPS Connundrum - and solution

[Gigaron]

^ Awesome thanks so much for the reply! I have a rack mounted Eton already.. so from reading the other posts in the thread, I won't have to change the PW frequency settings..



Actually you might. My PW originally ran at 65 Hz and the Eaton complained - bitterly, and ran down the battery trying to compensate.

I asked Tesla to change the PW frequency to 62 for me.

 

[cwied]

Ok. So I am not so daft after all.. . That is what I thought.. So much misinformation out there.. What UPS's are you using? Thanks!

I would point you to this reference page: Uninterruptible power supply - Wikipedia

I think what you're calling a "real UPS" is a double-conversion UPS. While this is certainly the gold standard for UPSs and also has the benefit of power conditioning, most people would still call standby or line interactive UPSs "uninterruptible." As far as I know, my consumer-grade APC UPS is a standby UPS. It has a 6-10 ms switchover time and I have never had any issues with it.

 

[Jay Gatsby]

^ Awesome thanks so much for the reply! I have a rack mounted Eton already.. so from reading the other posts in the thread, I won't have to change the PW frequency settings..



Actually you might. My PW originally ran at 65 Hz and the Eaton complained - bitterly, and ran down the battery trying to compensate.

I asked Tesla to change the PW frequency to 62 for me.

Why isn't that a simple configuration in the app?

 

[Jay Gatsby]

I'm not sure you guys in the US realise just how hard it is to get an installer to do anything including aftermarket service here in Aus.. I've been waiting 10 months already to even get the panels and inverter.. the battery has been "coming" 12 months. It's still not here.. So this frequency adjustment is just a quick call to Tesla HQ support in the US? right?

 

[RKCRLR]

T

I'm not sure you guys in the US realise just how hard it is to get an installer to do anything including aftermarket service here in Aus.. I've been waiting 10 months already to even get the panels and inverter.. the battery has been "coming" 12 months. It's still not here.. So this frequency adjustment is just a quick call to Tesla HQ support in the US? right?

There isn't such a thing as a quick call to Tesla tech support in the US...
But, yes, this can be done remotely by Level 2 tech support. It can take a week or so to get done.

 

[drtimhill]

I am confused.

Can't installing a powerwall 2 mean the home owner can remove all the smaller UPS from the house?

I thought the Tesla Powerwall 2 with Tesla backup gateway 2 could itself act as a true UPS?

Am I mistaken here?

Thanks!

No, but they can be smaller, since all they need to do is sustain the load while the PW switches in (and they also provide surge protection too).

 

[jboy210]

I'm not sure you guys in the US realise just how hard it is to get an installer to do anything including aftermarket service here in Aus.. I've been waiting 10 months already to even get the panels and inverter.. the battery has been "coming" 12 months. It's still not here.. So this frequency adjustment is just a quick call to Tesla HQ support in the US? right?

To get my frequency changed I called Tesla energy and told them the make and model UPSes I had. The person on the phone created a ticket and sent it to a Level 2 tech for evaluation. About a month later I got a message saying they dropped the max frequency to 62 Hz. No one had to come out. I assume it was a configuration change they made to my TEG.

 

[BGbreeder]

It is a configuration setting in the Gateway (TEG).

 

[iollmann]

Jeep, I was contacting many UPS manufacturers yesterday as to the 65 Hertz issue. CyberPower, unfortunately, told me that every UPS they sell only serves as a pass-thru at 60 Hertz plus or minus THREE Hertz. You should test it, but I believe you will find that the Cyberpower UPS you have will NOT see the PW2 power stream as 'good' power while it has incresed the Hertz frequency to prevent the solar inverters from functioning.

In looking at the specs for the Eaton UPS you pointed to, it DOES look like it will work. The acceptable Hertz frequencies are 46-70 Hertz so may be OK. I'm going to try the Minuteman solution but the Eaton looks like it has more range and is somewhat equivalent in price:

Eaton 5S UPS | EatonGuard.com

I have an Eaton for use with my computer. It works just fine with the Powerwalls for the last year or two, and will bridge the gap in the rare circumstances when the power wall response time isn’t fast enough to avoid a momentary but data loss causing drop in power.

Im still looking for a solution however for the other end of my house, where I am looking for extended backup for some low power Wi-Fi units should the power walls discharge completely. Here I find Eaton to be a little disappointing. If you look at their power graph, even with 4 extra battery modules they only last 10 hours at low load. With none, you are lucky to get an hour. I feel like there should be a solution for extended backup of < 20W load for a few days. Maybe I am fussing too much. The sun has to come out eventually and recharge the powerwalls. It is impossible to overstate the Mordor like conditions caused by a forest fire. It is also a time when you might want to call the fire department.

 

[BIC1]

I have 3 CyberPower units. Did have frequency issue. Called Tesla and they changed the PW2 frequency. No further issues with CyberPower units.

 

[miimura]

I have an Eaton for use with my computer. It works just fine with the Powerwalls for the last year or two, and will bridge the gap in the rare circumstances when the power wall response time isn’t fast enough to avoid a momentary but data loss causing drop in power.

Im still looking for a solution however for the other end of my house, where I am looking for extended backup for some low power Wi-Fi units should the power walls discharge completely. Here I find Eaton to be a little disappointing. If you look at their power graph, even with 4 extra battery modules they only last 10 hours at low load. With none, you are lucky to get an hour. I feel like there should be a solution for extended backup of < 20W load for a few days. Maybe I am fussing too much. The sun has to come out eventually and recharge the powerwalls. It is impossible to overstate the Mordor like conditions caused by a forest fire. It is also a time when you might want to call the fire department.

If your devices use wall-wart power supplies and the electronics have DC input, you can build or buy a Lithium Ion battery and use a voltage regulated output that will have very high efficiency, and therefore long runtime for the battery size. However, I don't know of any plug and play solutions to do this.

 

[mspohr]

If your devices use wall-wart power supplies and the electronics have DC input, you can build or buy a Lithium Ion battery and use a voltage regulated output that will have very high efficiency, and therefore long runtime for the battery size. However, I don't know of any plug and play solutions to do this.

I have a Bluetti EB3A which has a UPS mode. You leave it plugged in and devices connected (12v or 120v). The battery is 270 Wh which should run small things a long time.

 

[SSonnentag]

This does not describe my experience. I use Time Based Control and when the Powerwalls are in Standby there is an interruption when the grid goes down. The interruption is sufficient to reboot computers and even my LCD TV will shut off and Tivo boxes will reboot. I have kept all my UPS units in place from before I got Powerwalls. My solar also shuts down for 5 minutes due to the interruption.

You can see when the power outage was in this chart. The solar was exporting at that time.
View attachment 400933

If you are running in Self-Powered mode and there is essentially no grid power flow, then of course, there will be no interruption when the grid goes down.

Our powerwalls are running in backup mode. With 44 power outages last year alone, we never once lost power to an electronic device. Computers stay up, TV, clocks, everything. Apparently not all powerwall configurations/installations are created equal.

 

[CWhite]

The Powerwalls are the same but the devices are different. Most UPS units have a problem with the Powerwall default 65hz @ full charge. Everything in our house works fine running on backup except the 3 UPS’s, a couple dimmable LED wireless remote ceiling fan lights and our fancy new Heat Pump. The heat pump literally went off-line and would not function when running off the Powerwall. Once Tesla set the hz down to 62 everything runs fine.

 

[jrweiss98020]

The UPS units do not have a "problem" - they are doing their jobs! The UPS is SUPPOSED TO protect against over- and under-voltage AND -frequency. The ATX power supply spec has a 63 Hz limit, so it is GOOD that the UPS cuts in at 65 Hz!

My Powerwalls take less than a second to switch over, but I have seen reports of 2-3-second turnover times. Still, mine are too slow for some sensitive electronics, so using a UPS is a good idea regardless.

 

[CWhite]

Perhaps my phrasing was poor. The UPS units look for many “problems” with the incoming power, incorrect frequency is one of these problems. The Hz output of the powerwalls is the problem. My powerwalls switch over so quickly we don’t even see the lights flicker.

 

[Blindsay]

Hey all,

Been reading up on this issue as I have run into it myself. I want to contact tesla about lowering the pw2 from 65hz to something sub 63hz (the limit of my ups) but from what i am seeing is this depends on your solar inverter correct?

This is my solar inverter - Fronius Primo 6.0-1 208-240


How do I figure out what I can have tesla lower the PW2 down to without causing any other issues?

Thanks!

 

[jjrandorin]

Hey all,

Been reading up on this issue as I have run into it myself. I want to contact tesla about lowering the pw2 from 65hz to something sub 63hz (the limit of my ups) but from what i am seeing is this depends on your solar inverter correct?

This is my solar inverter - Fronius Primo 6.0-1 208-240


How do I figure out what I can have tesla lower the PW2 down to without causing any other issues?

Thanks!

You dont, actually. Tesla calculates what they will lower it to based on the equipment you have. In other words, they will tell you what they will lower it to, you dont tell them what to lower it to (ideally).

I mean you can request something lower but they are going to lower it to something that works with your equipment. They may ask for information about your equipment if they dont have it.

 

[Blindsay]

Got it, and that is dependent on my solar inverter right? So if my equipment prevents me from going lower than 63hz. My only options would be to replace the inverter or get a ups that can accept higher but also properly fix it as i dont want to send 65hz to my computers

 

[aesculus]

Got it, and that is dependent on my solar inverter right? So if my equipment prevents me from going lower than 63hz. My only options would be to replace the inverter or get a ups that can accept higher but also properly fix it as i dont want to send 65hz to my computers

It's not dependent just on the solar inverter but other items you have that are frequency sensitive. So it could be lighting, your microwave, UPS etc. Make yourself a list of items that don't behave properly at 65 hz and tell Tesla what is not working. They should then drop it to something more reasonable (ie for me it was 62.5 hZ). I still have some light switches that don't like 62.5 Hz but can live without those so NBD.