Powerwall 2 + UPS Connundrum - and solution

[Gigaron]

I have a 10.5 kWh system with 2 Powerwall 2s. I also have 2 different models of the APC 1500. One powers my computer and the other solely powers the cable modem and router.

I have a Kaco Blueplanet 5002 which completely turns off after dark -- even the display is blank. I had 2 power outages last night well after dark and in both cases, the UPS kicked in and then died since the outages were > 60 minutes.

I don't believe that the UPS kicked in when I had power outages during the day.

 

[zanary]

I have a 10.5 kWh system with 2 Powerwall 2s. I also have 2 different models of the APC 1500. One powers my computer and the other solely powers the cable modem and router.

I have a Kaco Blueplanet 5002 which completely turns off after dark -- even the display is blank. I had 2 power outages last night well after dark and in both cases, the UPS kicked in and then died since the outages were > 60 minutes.

I don't believe that the UPS kicked in when I had power outages during the day.

Maybe I'm confused, but since you have two Powerwall, why do you need the additional APC 1500 battery backups? the Powerwall will kick in during an outage, and it's run time is dependent on the reserve percentage you set and the electrical load in your load center.

 

[miimura]

Maybe I'm confused, but since you have two Powerwall, why do you need the additional APC 1500 battery backups? the Powerwall will kick in during an outage, and it's run time is dependent on the reserve percentage you set and the electrical load in your load center.

You still need UPS to cover loads that you want to be truly un-interruptible. At my house, also with two Powerwall 2's, if the Powerwall is not supplying power to the house (ie. it's in Standby due to TBC), there will be a brief interruption while the transfer switch opens and the Powerwalls ramp up their power. I also have two APC SmartUPS 1500 units that have been working well with the Powerwalls.

However, it's not clear to me why his APC units went to battery for extended periods while the Powerwalls were still running. I also don't know what the Kaco unit is and what it has to do with the rest of the systems in his house.

 

[zanary]

You still need UPS to cover loads that you want to be truly un-interruptible. At my house, also with two Powerwall 2's, if the Powerwall is not supplying power to the house (ie. it's in Standby due to TBC), there will be a brief interruption while the transfer switch opens and the Powerwalls ramp up their power. I also have two APC SmartUPS 1500 units that have been working well with the Powerwalls.

However, it's not clear to me why his APC units went to battery for extended periods while the Powerwalls were still running. I also don't know what the Kaco unit is and what it has to do with the rest of the systems in his house.

Hmm, that's interesting. I'm in the same boat as you, but I don't have extra UPSs, when we we lost power last night, I had no idea. Nothing flicker, nothing lost connection, nothing rebooted. In fact I had no idea I lost power until I got an APNS on my Tesla App indicating that I'm running on Powerwall because of a power loss (the APNS arrives what looks to be 5 or 6 minutes after switching).

 

[cr0ntab]

I ended up just getting a few of these:

https://smile.amazon.com/AmazonBasics-Standby-UPS-400VA-Outlets/dp/B073Q48Z95/

To plug monitors and a few computers into, things that were very sensitive to power fluctuations.

During a transfer event on the powerwall these kick in for half a second and go back to normal.

Monitors and computers don't turn off and everything is happy.

There were a few other threads about solid state batteries and such so you don't have too replace the batteries every few years.

However, at $35 cost it's hard to recoup that investment in a meaningful amount of time.

 

[vlad_kalish]

I have a 4 kWh system with 1 Powerwall 2. I also have a UPS: CyberPower LX1100G, which powers my computer, the cable modem, and router.
Last night (10:00 PM) I had a power outage and UPS kept on beeping (for an hour) until it died. While beeping it showed 60Hz on its display.
At the time of power outage, my Powerwall2 was 100% charged and my Tesla S was also charged and plugged in.

Will do some power outage testing to see my frequency...

 

[NinjaVece]

Hmm, that's interesting. I'm in the same boat as you, but I don't have extra UPSs, when we we lost power last night, I had no idea. Nothing flicker, nothing lost connection, nothing rebooted. In fact I had no idea I lost power until I got an APNS on my Tesla App indicating that I'm running on Powerwall because of a power loss (the APNS arrives what looks to be 5 or 6 minutes after switching).

Zanary, the relay snaps shut when power is lost and at the same instant tells the Powerwall inverter to begin providing AC power. There will be at least a number of milliseconds that there will be no cycles as that changeover occurs. Some electronics can handle it, others can't and will either reboot or simply shut off. If you are maintaining a Network Attached Storage device (NAS) or other unit that you want to make sure does not do either of those things, it is wise to get a UPS that will provide seamless power over the transition from grid power to the Powerwall inverter.

Just a heads up.

 

[NinjaVece]

I have a 4 kWh system with 1 Powerwall 2. I also have a UPS: CyberPower LX1100G, which powers my computer, the cable modem, and router.
Last night (10:00 PM) I had a power outage and UPS kept on beeping (for an hour) until it died. While beeping it showed 60Hz on its display.
At the time of power outage, my Powerwall2 was 100% charged and my Tesla S was also charged and plugged in.

Will do some power outage testing to see my frequency...

Almost can guarantee you it has to do with the fact that your PW2 was fully charged and the unit increased the Hz to 63 to shut down your solar panels. If your UPS is REALLY sensitive, it will see the 63 Hz as 'bad' power and stay in battery mode. If you are not using much power in the house, the PW2 will take about 20-30 minutes to get down to 96% power and then the unit will flip back to 60 Hz to reenable the solar panels. If usage is low, the panels will recharge the PW2 and it will again raise the Hz to 63 to disable them. This will cycle until the sun goes down or usage increases in the house beyond the solar input.

It was likely during that initial 20-30 minutes that your UPS did not like the house power (at 63 Hz), ran off its battery and then eventually died, taking everything behind it with it. The ironic thing is that when the PW2 resets to 60 Hz to allow solar input (in those cycles), the UPS will gladly start recharging back as it looks like 'good' power. But all your devices behind the UPS are already off.

The PW2 used to go all the way to 65 Hz (my initial reason for starting this thread) but more recent firmware updates limit it to 63 Hz, which most UPSs will see as 'good' power. Look at your specs to see what your UPS is supposed to see as good as to the Hz level.

 

[wbhokie]

Anyone figure out some "good" proven UPS systems that work when the powerwalls are providing power and survive the changeover? @cr0ntab did those amazon basics ones work for you?

 

[cr0ntab]

Anyone figure out some "good" proven UPS systems that work when the powerwalls are providing power and survive the changeover? @cr0ntab did those amazon basics ones work for you?

Yep, they're working great.

I haven't done a full suite of testing though. Not sure how they'll perform during a daytime outage when the powerwalls are frequency shifting to shut down the inverter.

For a standard flip they've proven themselves for me.

 

[PBBear]

Anyone figure out some "good" proven UPS systems that work when the powerwalls are providing power and survive the changeover?

Eaton 5S range (http://powerquality.eaton.com/Products-services/Backup-Power-UPS/5S.asp) auto-detects 50Hz/60Hz, and accepts a range from 46Hz - 70Hz. We're nominally 50Hz in Australia, but never had a problem with the PW2 ramping to 56Hz (as displayed on the UPS display). Always check the specs.

 

[wbhokie]

Yep, they're working great.

I haven't done a full suite of testing though. Not sure how they'll perform during a daytime outage when the powerwalls are frequency shifting to shut down the inverter.

For a standard flip they've proven themselves for me.

Excellent. Just had our first power outage last night and my older UPS units didn't detect the changeover. Tech support said that when powerwalls are full (As I use my powerwall only in backup mode) that the frequency can spike up to 65-67 Hz, so the UPS units went to battery mode. When the powerwalls got to around 90% or so capacity the UPS units recognized the power as good again but their batteries wouldn't have latest that long. I'd rather have something that can survive the small changeover time and recognize the powerwall power as good.

Thank you! Most UPS systems I've seen that advertise that range (up to 70Hz) are pretty expensive and not worth it for the few seconds of backup I need.

@cr0ntab If you don't mind me asking - how do you know that those amazon units kicked on or off? I ask because they say they are only 50-60hz

 

[wbhokie]

I went back and re-read this thread again to see some of the independent testing some of you did... looks like I am going to have to see what the measurements are on my specific system if I simulate a power-off test to see if I need to bother Tesla to get it adjusted. Maybe my existing UPS units will work in that case and I won't need to invest in some new units.

 

[cr0ntab]

@cr0ntab If you don't mind me asking - how do you know that those amazon units kicked on or off? I ask because they say they are only 50-60hz

Well I purpose bought these UPSs because my monitors are quite sensitive to the power cutover. They would turn off and back on during a flip.

Since installing these I haven't had any of those issues, and we've had 2 unplanned outages since.

So for me, that's a win.

In terms of "kicking off" - one of the outages was about an hour long. So for the small bit of equipment on the UPS it held up for at least an hour. I don't know the exact power draw on the UPS and how long it "should" last, but an hour is quite a bit of time to stay on such a small battery.

From that, I made the assumption that the small UPS picked up the load for a few seconds of cut over, and resumed normal operation thereafter.

I'll have to be more vigilant during these events to see exactly how things perform.

 

[wbhokie]

Well I purpose bought these UPSs because my monitors are quite sensitive to the power cutover. They would turn off and back on during a flip.

Since installing these I haven't had any of those issues, and we've had 2 unplanned outages since.

So for me, that's a win.

In terms of "kicking off" - one of the outages was about an hour long. So for the small bit of equipment on the UPS it held up for at least an hour. I don't know the exact power draw on the UPS and how long it "should" last, but an hour is quite a bit of time to stay on such a small battery.

From that, I made the assumption that the small UPS picked up the load for a few seconds of cut over, and resumed normal operation thereafter.

I'll have to be more vigilant during these events to see exactly how things perform.

While true, they only technically need to last until the powerwall stabilizes its power frequency. From what I read previously, this happens in the mid 90 percentile. I do agree that those little UPS units have very little power though and shouldn't last long at all. The units I had powering things like routers seemed to last long enough for the powerwall to stabilize since their power draw was lower. The UPS units I have to backup computers and my home theater projector would not.

The problem with amazon basics products is that there are no kinds of spec sheets or websites that you can query to get more detailed information. So there is no way to find out the +/- on their supported power range at 50/60Hz. Their prices and power sizes are great though! So if they do in fact work they would be exactly the kind of product I would need, otherwise I'd have to switch to something like the Eaton products. I have asked

 

[cr0ntab]

@wbhokie

I was able to do a bit more testing this afternoon.

I shut off my main breaker and let the powerwalls takeover the house.

Solar was on, and putting out 4.8kW of power, 4.2kW of which was going to the batteries.

At 97% the AC frequency went high and the inverter detected that and shut off.

I went out to the inverter and verified that error.

All of my home UPSs were happy even with the high frequency.

I couldn't for the life of me find my Kill-A-Watt to verify what the actual frequency was, but the inverter thought it was too high.

To further verify my experiment I unplugged the UPS.

During this unplugged condition (which I would assume is the same as a "dirty" power condition) the led starts flashing and the unit started beeping.

It kept doing so until I plugged it back in.

All of this was enough of an experiment for me to continue purchasing these little guys for things that need 100% power uptime, even if it's just for the short blip of the cut over.

 

[wbhokie]

@wbhokie

I was able to do a bit more testing this afternoon.

I shut off my main breaker and let the powerwalls takeover the house.

Solar was on, and putting out 4.8kW of power, 4.2kW of which was going to the batteries.

At 97% the AC frequency went high and the inverter detected that and shut off.

I went out to the inverter and verified that error.

All of my home UPSs were happy even with the high frequency.

I couldn't for the life of me find my Kill-A-Watt to verify what the actual frequency was, but the inverter thought it was too high.

To further verify my experiment I unplugged the UPS.

During this unplugged condition (which I would assume is the same as a "dirty" power condition) the led starts flashing and the unit started beeping.

It kept doing so until I plugged it back in.

All of this was enough of an experiment for me to continue purchasing these little guys for things that need 100% power uptime, even if it's just for the short blip of the cut over.

Thanks for the testing! I appreciate it!

I did post a product question on amazon, but the internet being what it is, people actually took the time to make responses like "I dont know", or "It's a cheap UPS so just be happy". Why do people bother reading random product questions and answering if they don't know the answer?

Newegg also sells some Eaton 3S550 VA UPS units for $68.99 which are 330W and are rated up to 70hz. Not much more expensive than the 600VA amazon basics models. I still plan to test my own powerwalls and see what frequency they are using because your powerwalls and mine might not be operating the same also.

I read some reviews on the amazon basics units and it was hinted that they were the same internals as cyberpower units, which would mean they would operate to 63Hz. So if you could find your Kill-A-Watt that would be helpful. I will find mine and see what it says.

Who knows, maybe I'll just order one of the amazon ones and just test it and return it if it doesn't work.

 

[K-MTG]

Anyone using the 1500AVR UPS from CyberPower? I have two of those (one with & the other without pure sine wave). And I have two cheap APC 600VA.

I don't have any powerwall yet (still waiting) but if you have any 1500VA UPS recommendation (ideally with pure since wave). Let me know.

 

[tjka4231]

I have a CyberPower 1500PFCLCD UPS connected to my desktop Dell PC. It's a Pure Sine Wave UPS that is needed for my PC's active power supply. There was one recent grid power outage that lasted for a minute in which my 2 Powerwalls took over powering the house but during the grid outage the UPS did switched over to its own battery to power my Dell PC before switching back to AC power.

 

[K-MTG]

I have a CyberPower 1500PFCLCD UPS connected to my desktop Dell PC. It's a Pure Sine Wave UPS that is needed for my PC's active power supply. There was one recent grid power outage that lasted for a minute in which my 2 Powerwalls took over powering the house but during the grid outage the UPS did switched over to its own battery to power my Dell PC before switching back to AC power.

Did it switch over to the powerwall source? Or ran on its battery till grid power was restored?