Inverter Farked??

TheFew · 5 Jun 2022 at 17:00

Hello,

I'm after some advice on my inverter, from those who know about them!

I have a Sunnyboy 2500 HF that is connected to 13 x 240w panels.

The system seems to have been installed in 2012 by the previous owner (so out of warranty).

I don't look at the inverter often, only really grabbing a meter reading every quarter when asked to by the FIT provider.

When i looked yesterday however, my spider sense suggested the inverter may not be behaving as it should (noting it was early evening when I looked).

So what seems to be wrong?

First the inverted has 4 LEDs on it. From the instructions it should have a solid green light when generating power and a flashing green light when awaiting sufficient illumination to begin generating. Or a solid red light when there is an error. It has no lights whatsoever illuminated.

The main LCD works however and does show the firmware details etc when engaged. Oddly however, it showed no power generation nor any for the current day (it had been sunny).

In the last 24 hours (mostly overcast). There has been no power generation what so ever.

So the lack of any LED being illuminated and the lack of any power generation in the last 24 hours, and a lack of a "day" generation reading for a sunny day does make me suspect that there is an issue...

What does the forum think?

If the answer is, I need a new inverter - a there any recommended companies to contact? I am wiltshire based if that makes any odds.

Thanks.

radderfire · 5 Jun 2022 at 17:47

Have you checked the manual? I found this:

http://www.windandsun.co.uk/media/171832/Sunny-Boy-2000-2500-3000HF-Installation-manual.pdf

TheFew · 5 Jun 2022 at 18:51

Yes. Thanks. I did download a copy of the manual and have a printed one left by the previous occupants.

The manual is a bit thin however and does not really have any troubleshooting guidance.

The manual suggests with no sun on the panels you should see a green flashing light. However I have seen a youtube video, which suggests at nighttime there would be no lights visible. I suspect the youtube statement is inaccurate, but I was hopingto hear from someone with direct experience and knowledge.

gpuerrilla · 5 Jun 2022 at 19:46

Any good?

TheFew · 5 Jun 2022 at 20:00

gpuerrilla said:
Any good?

Thanks. Looks like a useful local company. May give them a bell.

I have seen the error codes before but they are no help however, as the system is not showing an error code... just seems not to be working as expected.

Journey · 5 Jun 2022 at 20:07

If it is faulty don't just assume it will be cheaper to repair it than replace it, 4KW inverters can be had for under £450, and you'll get a decent warranty with a new one. Plus some of the older inverters were terrible, so maybe better replacing it if it turns out to be faulty.

TheFew · 5 Jun 2022 at 20:26

Journey said:
If it is faulty don't just assume it will be cheaper to repair it than replace it, 4KW inverters can be had for under £450, and you'll get a decent warranty with a new one. Plus some of the older inverters were terrible, so maybe better replacing it if it turns out to be faulty.

Hi, yes, that does seem to be the common view. Also seems that the model I have often fail after 5 years. So looks like I may soon be patting with around £750. But annoying as I am looking to sell the house soon... but I guess working solar will be attractive to future buyers.

gpuerrilla · 5 Jun 2022 at 20:54

If it is faulty I would replace before too many good weather days are lost this summer (oh and the installers are available before they are too busy). With price of energy way up compared to last year, you want to shave off your bills as much as till the house is sold is way I would look at it.

LuckyBenski · 7 Jun 2022 at 01:41

How come we've all assumed the issue is the inverter, not the bank of panels or connection? Am I missing something?

FWIW we have a pair of 1200W Sunnyboy units and they only power up at all once there's some daylight. Then there are 3x LEDs which effectively indicate the stages of light up until normal generation. So aside from the display on your unit, I would take "no LEDs" to mean possibly no PV feed.

Rroff · 7 Jun 2022 at 02:06

Generic brand (and even many better brand) inverters only tend to last around 10 years of decent usage.

gpuerrilla · 7 Jun 2022 at 08:02

Most start with a 5yr warranty. I think that would speak for itself. However as benski says investigate further as you might spot something.

TheFew · 7 Jun 2022 at 10:07

LuckyBenski said:
How come we've all assumed the issue is the inverter, not the bank of panels or connection? Am I missing something?

FWIW we have a pair of 1200W Sunnyboy units and they only power up at all once there's some daylight. Then there are 3x LEDs which effectively indicate the stages of light up until normal generation. So aside from the display on your unit, I would take "no LEDs" to mean possibly no PV feed.

Fair point. It could be no input voltage. Not totally sure how I would check that on the system..

Journey · 7 Jun 2022 at 10:45

TheFew said:
Fair point. It could be no input voltage. Not totally sure how I would check that on the system..

Measure the MC4 connector input voltage using a DVM. Easy to do, plenty of guides online if you are unsure.

TheFew · 7 Jun 2022 at 11:00

Journey said:
Measure the MC4 connector input voltage using a DVM. Easy to do, plenty of guides online if you are unsure.

Thanks. Looks doable. I did try taking the cover off of the DC isolator switch to measure there, but the cover did not want to come off easily, so I did not chance it.

Would you happen to know if the MC4 connections are push fit (thus just pull out) or if they are twisted in? I don't want yo break anything.

Thnaks

TheFew · 7 Jun 2022 at 11:58

OK. So seems that the mc4s are push fit and a little screw driver can prise them open.

So I turned off the ac and dc power and the fuse board for good measure.

Took the bottom black panel off of the inverter (the unit with thr fan).

I opened up the mc4 connectors, turned the dc isolater and fuseboard back on...

Applied the multimeter probes, and could not get a dc voltage reading. I had check the meter using a 1.5v battery, so seems I had the correct setting for dc.

So either no power is coming from the panels or I am testing wrong...

LuckyBenski · 7 Jun 2022 at 12:57

TheFew said:
Applied the multimeter probes, and could not get a dc voltage reading. I had check the meter using a 1.5v battery, so seems I had the correct setting for dc.

So either no power is coming from the panels or I am testing wrong...

Make sure you're ranging the meter right - IIRC solar panels can deliver up to 175V DC so definitely start on your highest setting.

TheFew · 7 Jun 2022 at 13:47

Yeah. Set the meter to 600v dc, and also inserted some 6mm wire into the connectors (as my multimeter probes are not very long). Still nothing...

Guess it is time to get someone in!

LuckyBenski · 7 Jun 2022 at 14:03

That's a shame - a broken wire is not a difficult fix, but I think a dead panel can break the continuity of the entire array.

TheFew · 7 Jun 2022 at 14:13

LuckyBenski said:
That's a shame - a broken wire is not a difficult fix, but I think a dead panel can break the continuity of the entire array.

Almost hoping it is some how the inverter and not a duff panel!

TheFew · 8 Jun 2022 at 13:52

Managed to test the voltage across the DC isolator.. nothing. So clearly an issue with the panel array, not the inverter.

Learning point for the day... the switch on the isolator box needs to be in the off position for rhe cover to come off... previous I had it in the on position, hence why I could not open the box!