Skybox user feedback

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Skybox user feedback

Post by wahlmanc »

Hi, I'm new to the forum, and was looking into purchasing a Skybox to update/upgrade my small off grid setup. Pretty much starting over, as my old system was 24v based, and my flooded lead acid batteries have reached the end of their life. I want my new 48v system to operate in a grid zero config and occasionally use the batteries down to a certain voltage, while keeping a portion of capacity in reserve for power outages. Have already ordered 10kWh of LiFePO4 batteries.

Can any of you share the pros and cons you've experienced with the Skybox? Did it meet your needs / operate as advertised? Will it work for the needs I've stated above? If you had to do it all over again, would you purchase? Just looking for some real user feedback to help with my decision. Thanks!
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Re: Skybox user feedback

Post by wahlmanc »

Quiet group.... :grin:
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Re: Skybox user feedback

Post by fcwlp »

What do you need to power? The Skybox is a 5,000VA system with limited surge capability.
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Re: Skybox user feedback

Post by sbrownian »

No requirements mentioned, other than 'small' and "have 10kwh of LiFePo" ordered.
Information, you get not; if incorrect question, you ask..
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Re: Skybox user feedback

Post by raysun »

I'm not a Skybox user so have little specific to add, but there are lots of posts on the subject that will turn up by searching for "Skybox".

One nugget I've gleaned from scanning the posts is Skybox seems particular about battery models used. Hopefully the battery on order is compatible.

Skybox has several "smart" operating modes. Much of the discussion on the Skybox threads seems to center around the differences between what the user thought the Skybox does (or should do in their view) and how it actually operates.

I'd suggest detailing your proposed use case as completely as possible, including expected loads, charging capabilities, etc., so that the experienced Skybox users can have a clearer picture to work with.
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Re: Skybox user feedback

Post by wahlmanc »

Ordered 2.4 kW of solar panels (8 panels) with Voc of 40V - wired in series gives me 320 V - string1
Currently have 1.2kW of solar on existing string (6 panels) with a Voc of 22.5 - wired in series give me 135V - string 2

EG4 Lithium batteries w/ BMS at 48v - 5.2kWh - 2 wired in parallel

Minimum critical loads are 2 deep freezers and 1 refrigerator

Want to offset grid power without selling back to utility and have backup battery power for occasional power outages to power the above critical loads. Want ability to also hook up a portable generator to assist when grid is down and inclement weather occurs

Hopefully that gives some background info. I do have some concerns with how the skybox may work with my battery. Is it battery agnostic? Can it operate well with custom defined battery settings and not talk to the BMS? Seems like the unit is geared towards compatibility to the more expensive battery manufacturers. Does anyone have a homemade battery or Chinese off branded battery in use with their skybox?

I see a lot of posts of folks rebooting the unit to clear unexpected errors. Is this a regular occurrence? How often are firmware updates released?
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Re: Skybox user feedback

Post by Mike Curran »

Skybox will accept 2 separate PV array strings, but the arrays must be of identical modules because Skybox applies just one MPPT algorithm to both arrays. Also, each array must have a minimum 250V open circuit voltage, else Skybox will not "turn on". Your string 2 would not work with Skybox. Maximum 5000 watts of DC PV input.

You can set up custom battery parameters with skybox. It also has pre-programmed parameters for those expensive lithium options you referred to. It will operate without a connection to your battery's BMS.

Skybox has inputs for both grid and generator. The current firmware does not allow the generator to recharge your battery unless there's a minimum 600W load - a "feature" I dislike, and for which I haven't seen an explanation. The generator will support your loads during an outage.
Want to offset grid power without selling back to utility and have backup battery power for occasional power outages to power the above critical loads.
Skybox will certainly meet your operational needs using "non-export" mode, as described here (along with other options):
Screenshot_20210720-212009_Adobe Acrobat.jpg
The last firmware update was in August, 2020.

This webinar may be informative:
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Re: Skybox user feedback

Post by Ampster »

raysun wrote: Mon Jul 19, 2021 8:47 pm .....

One nugget I've gleaned from scanning the posts is Skybox seems particular about battery models used. Hopefully the battery on order is compatible.
I have been using a Skybox for three years with two different battery chemistries and have had no issue with battery compatibility. It is simply a matter of setting the correct constant current and constant voltage for the battery configuration being used. It may be important for Skybox users to rely actual experience from other Skybox users rather than compound hearsay.

However the Skybox was designed to be grid interactive and if the OP is off grid another Ouback product would better suit his needs. The OP talks about being off grid in one post but in another post mentions a grid connection.
Drive Tesla Model X and Model 3 which are charged at Super Off Peak rates.
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Re: Skybox user feedback

Post by Electrictrauma »

I got some different answers from tech support when I started, until I was referred to a consultant ….you are kinda on your own. And yes the faults can be mysterious, especially if they seem to occur randomly and cause you to have a reboot. I installed a new battery bank and still get a fault every few days. I experiment with the settings and hopefully will get it dialed in.
So that is my biggest complaint…alot of little quirks and sometimes no answers as well as being an early adopter and paying way more than todays list price!
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Skybox "Bristlecone2" with 5 kWh SLA (not currently active since "stacked" operation not working)
Skybox "Cottage1" with 14.3 kWh LiFePO4 (used for power outage backup)
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Re: Skybox user feedback

Post by mhspohr »

To your battery question.
I have used both SLA and LiFePO4 batteries with my Skyboxes. You have access to a lot of battery parameters which you can customize to your batteries. There are several battery threads to get you started on setting parameters. The defaults provided are limited to several brands of batteries but you can modify just about everything about the batteries.
I've set up my LiFePO4 batteries (Chinese 280 ah cells 16S) and they seem to work well with the parameters I've set. I started with the Simplifi preset and then modified a few things (size, ah, etc.). Some of the things like min and max voltage can be changed... it seems these batteries have longer life if you keep them between 20% and 80% rather than fully charging them.
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