XW+ 6848 - Does it require batteries? (yes)

[ncs55]

Something about the SMA SPS does NOT add up. They are claiming that it provides enough back-up power to run a normal sized fridge, phone, TV, etc. If their inverter has these benefits - which no other inverter on the market has - then why isn't every homeowner buying this model (SMA is currently the #5 inverter in US residential market)? Does the inverter actually provide these benefits (I thought a fridge start up power is 2.4kW, so the 1.5kW would NOT work)? Are homeowners not interested in running an extension cord to these devices? Is there an issue because the solar power is intermittent, and so people don't see this as a reliable form of back-up?

The SPS is a nice function, but only works when there is no grid. It does what it claims from what I see. I am not sure what inverters are ranked above the SMA, but for longevity, a well built product and excellent customer and installer support, they should rank higher. Fridge startups depend on the model and age of the fridge. Energy star units will work if they are in the parameters. From what I see when I do system checkups is that quite a few installers are not installing the SPS. And that is simply omitted so that their crews can move to the next job faster in most cases. I am usually the first one who asks the customer why it has not been installed. It is a nice add on to a system check and only takes about a half of an hour, but should have been included in the original installation and leaves a bad taste in the customers mouth when they have to hire another company to complete a job that was paid for already.

[sensij]

Something about the SMA SPS does NOT add up. They are claiming that it provides enough back-up power to run a normal sized fridge, phone, TV, etc. If their inverter has these benefits - which no other inverter on the market has - then why isn't every homeowner buying this model (SMA is currently the #5 inverter in US residential market)? Does the inverter actually provide these benefits (I thought a fridge start up power is 2.4kW, so the 1.5kW would NOT work)? Are homeowners not interested in running an extension cord to these devices? Is there an issue because the solar power is intermittent, and so people don't see this as a reliable form of back-up?

I think the SPS is more of a novelty. How often does power go out, when the sun is shining brightly enough to power anything useful, and someone is home and prepared to run an extension cord to a single device? Even for a refrigerator, at most you are talking about supplying maybe 4-5 hours of power... do your outages (in broad daylight) usually last longer than that? A fridge, kept shut, can go through a short outage without really causing a problem.

There are a few edge cases in which it could have some genuine utility (topping off power to a UPS, for example), but for most homeowners, I just don't see why anyone would go out of their way to choose SMA for just the SPS feature.

[ncs55]

I think the SPS is more of a novelty. How often does power go out, when the sun is shining brightly enough to power anything useful, and someone is home and prepared to run an extension cord to a single device? Even for a refrigerator, at most you are talking about supplying maybe 4-5 hours of power... do your outages (in broad daylight) usually last longer than that? A fridge, kept shut, can go through a short outage without really causing a problem.

There are a few edge cases in which it could have some genuine utility (topping off power to a UPS, for example), but for most homeowners, I just don't see why anyone would go out of their way to choose SMA for just the SPS feature.

It is kind of a novelty IMO. It is also nice to have. Some of my customers have regular and scheduled power outages and this usually happens in the morning and can last all day. It is a nice feature for them but not a great selling point for me. I sell SMA's because they are reliable when in a proper design, the company is solid and if there is a warranty issue SMA will have a new unit to you usually within 3 days.

[jflorey2]

Something about the SMA SPS does NOT add up. They are claiming that it provides enough back-up power to run a normal sized fridge, phone, TV, etc. If their inverter has these benefits - which no other inverter on the market has - then why isn't every homeowner buying this model?

Because most people don't need that benefit.

(I thought a fridge start up power is 2.4kW, so the 1.5kW would NOT work)?

The newer SPS is 2kW. And it will support a bit of surge, but the surge will be limited to the energy stored in the DC link capacitors within the inverter.

Are homeowners not interested in running an extension cord to these devices? Is there an issue because the solar power is intermittent, and so people don't see this as a reliable form of back-up?

Most of them just plain don't need it.

[jflorey2]

I have two Sunnyboy US inverters. One is 6 KW and one is 5 KW. They both have the 1500watt emergency power when grid is down. I'm wondering.
1. How to connect the two 1500 watt supplies into one 3000 watt supply.

Connect two 1500 watt AC to DC converters to the two outputs.
Use them to charge a 48 volt battery bank.
Use a 3000 watt inverter to convert back to AC.

Needless to say you would be much better off just doing a standard hybrid system. If you need that much backup power, just start with something like a GVFX3648, battery bank and a Midnite Classic CC.

[Amy@altE]

SMA's SPS was in response to the tsunami in Japan when everyone lost power. Even though there was a ton of solar, no one could charge their phones or radios, so communication was down after a few days. The SPS is designed to provide some emergency power as available. It is not intended to be a whole home backup.

[jflorey2]

SMA's SPS was in response to the tsunami in Japan when everyone lost power.

And in response to Hurricane Sandy, where a lot of people were taken aback when their solar power systems did them no good after they lost power.