SMA Sunny Boy inverter life expectency

[plannersteve]

I have an SMA Sunny Boy 7.7-US inverter for my grid tie system. There are 3 strings of 10 290W Hyundai panels and an SMA Rapid Shutdown device.

My first inverter lasted 15 months and was replaced under warranty. The replacement inverter lasted a little over three years and failed. Both units failed with an error code 7702, interference of device. Perhaps related to Grid Relay of inverter defective?

This seems like very short life for equipment like this. My initial installer is no longer in business so no help there. Believe I am no longer under warranty either.

Any ideas on the cause of these failures? Is it possible there is something wrong with the installation wiring? Or is short life not that unusual?

[peakbagger]

Are you suire on the warranty? Sunny Boys used to be 5 years with the ability to buy an extension

[plannersteve]

I'll check on the warranty. My understanding is 5 years from original install, but hopefully I am wrong. I did not get an extension.

[J.P.M.]

I'll check on the warranty. My understanding is 5 years from original install, but hopefully I am wrong. I did not get an extension.

What state are you in ? CA mandates a 10 yr. warranty.
SMA carries a 10 yr. mfg.'s warranty as well.

[plannersteve]

I am in Idaho. Original installation was put in service in November of 2017.

I looked at the original warranty again. It does appear that it is 10 years.

Still would like to know if there is something odd about the short life I am getting on these inverters.

[solarix]

That 7702 error is the bane of SMA inverters from a few years ago. Caused by the AC relay failing. Hang in there, the old, old ones that had 5 year warranties typically lasted 10 years. These newer ones (-40 or -41) have 10 year warranties and should go much longer than that. I'm surprised the replacement unit did the same thing.

[plannersteve]

That's encouraging, maybe. The latest one is a -40 with a manufacture date of 6/2022.

The one that recently failed was a -40 also, manufacture date of 10/2018.

The original was a -40 with a manufacture date of 11/2016.

[Calsun]

My Sunny Boy inverter was sold relabled and sold by Sunpower. Our inverter failed in September and we are told by Sunpower last week that the inverter is on "backorder" which means they have no units in production.

The large local residential and commercial solar reseller and installer found it necessary this year to switch to a different company for new installs. Of the companies they deal with the owner told me that Sunpower (and by extensions Sunny Boy) was by far the worst.

A warranty has value only if the manufacturer can provide a replacement part in a timely manner and Sunny Boy is not able to do this. Same problem with the all in one Tesla Powerwall. The local dealer has had customers waiting for 16 months to get a failed Tesla Powerwall replaced.

The emphasis on price above all else has resulted in companies cutting corners in manufacturing and so the failure rates are far higher with today's electrical equipment.

[plannersteve]

My replacement took about 5 weeks in total, but most of that time was delay of installer not SMA. My best guess is from the time they contacted SMA it took them about two weeks to receive the replacement. Perhaps even a little less.

Agree this kind of failure rate indicates cost cutting, bad engineering, or sloppy manufacturing practices.