Sun G Wind Grid Tie FAILURES

Short update on the Sun G for wind inverters.
I know many of you have been starving for wind these past few months but at this home the wind just does not stop,, and heavy winds. This past month my utility just issued me a $ 48.00 credit . I am using two WN 500's and one WN 750. All are feeding Sun G wind inverters.

Now what I am leading up too; All the inverters I mention will be 10.8-30 V
In these past few weeks I have had four inverters quit !
# 1 inverter first remained on full dumpload position so I had to diconnect the dump and just use it to feed the grid only. Then we had a grid failure and the inverter will not recconnect or reset. It recognizes the grid power but contiually brakes the turbine and will not make watts.
# 2 inverter , same as above but this one also had smoke curling out the vent.
# 3 inverter, same as # 2 . I opened this one to check the fuse, when trying to remove it the fuse pulled apart and I saw that one terminal of the fuse had been soldered solid to the terminal input. Lots of smoke from this one also.
# 4 inverter also decided to shut down but after replugging it again many times, it started working properly. Although it is working good at the moment I feel it is an accident waiting to happen.

Most of you know that Larry & I have done a lot of testing and sharing information back and forth regarding the grid tie setups. He also is using the same type of inverters and set up a mine with no problems to date ! The only difference has been the continuous heavy wind load on mine .

When these inverters are running correctly you could not ask for a better set up BUT when they FAIL, don,t forget they are a China made product and the customer after sales support is very difficult to obtain or very
expensive in shipping costs. ( that is if you are able to break through the language barrier which seems to become greater if you have a customer issue) We really need to identify an electronics repair center in N. America to doctor these failing electronics/ inverters.

I still have one setup of Sun G 300, 10.8-30 and Sun G 1000 22-60 for my WN 750 ( so far no issues)
Good job I did not sell my SWEA inverters because I was able to bring them back into use to save the day on my WN. 500 in the shop.

This has been a continous expensive experience trying to find the right equipment to match the right tubine for home use. Yes I have a lower utility bill each month and yes I did recieve a $ 48.00 utility credit but in two weeks I went through $ 1000.00 in Sun G inverters.
You do the math!

 

You have a dump resistor on the 10.8-30 volt SunG GTI ?
I have mine on the 22-60 volt GTI and nothing on the 10.8-30 volt GTI. The GTIs are tied in parallel.

 

Tom, on my 750 WN using a 300 , 10.8-30 & 1000, 22-60 I do not wire for the use of the dump due to being confident of not exceeding 1000 watts on a 750 watt turbine with furling.
I used the dump feature on turbines that used Sun G 10.8-30 only ! . " These did not have a parallel 22-60 inverter "

 

Thanks for the info.
Glad I left my 22-60 volt GTI hooked to mine then with no dump load on the 10.8-30 volt GTI.

 

Tom I cannot say for certain where the problem is but I am doubtful that it has anything to do with the dumpload feature.
Sorry if I am making it sound that way !
I did say one of the inverters had a faulty dump feature, but that was not the issue for the smoking and failure for all four to release the tubine.
What I was thinking was when there was a grid failure the inverter shuts down and also brakes the turbine, when the grid resumes the inverter powers up but does not release the turbine, it is staying in a braking mode and not completing circuit to create watts into the grid.
I am not the engineer but it would seem there might be a relay issue ! ?

 

Might be the relay.
The relay is a JQX-115F-I 12v 16a 250 vac
Hard to find but a guy on ebay selling them 5 at a time. Also could try manufacturer for some.

 

Tom, thanks for the info on the relay. At this point because some of them smoked there might be a chance some of the board melted too. I think this means they should go back to the manufacturer !
When I mentioned relays earlier I was just trying to "sound" smart ". lol. I would not know what a relay looked like if I was standing on it. I do have one that might get worked on by the fellow Larry mentioned. I also have bought from him and no issues yet . I would like to support Ronnie in learning how to do repairs on these units because it is badly needed to have a North American technician.

 

I was checking out the other controller board where I fried the relay. I did find one and got it fixed.Looks like they should not be using that relay in this GTI . It is too light. By the way I took the 22-60 apart and it has the same relay.
Best suggestion is to use the dump load terminals to trigger a Heavy Duty relay. Like I did with my dump load. That way the relay in the GTI only uses less than 2 amps on its relay and the Heavy Duty relay will carry all the power from the turbine. Has worked for me so far. That will keep you from frying another GTI and you will be able to use just the 10.8-22 volt and will not have to go to a parallel arrangement. What do you guys think? Messy little picture for you. I am not a Picasso Leamy has played around with relays more than I have. Maybe he could give a suggestion. I use that switch I bought for mine. But it is another $70 for that. Find the right relay and it will be a cheap fix without alot of fuss.

 

Good idea Tom,
Just remember that realy must be sized for all the amps from the turine going through it to the dump coils in a power outage. Could you please tell us what an HD realy is?
Thanks

 

I was wondering what HD was too. I think it means "Heavy Duty" so that would mean that the inverter dumpload feature would activate a separate heavy duty relay to to the dump coils solving the weaker relay problem. I'm I close?

 

Heavy Duty Relay like Windy Nation had for their 90 amp diversion . Only problem would be for the 22-60 volt range and or for just a 10.8-30 volt. . For the lower voltage a car Heavy Duty relay should work. But if running parallel I would have to see if I can find one that would work for that that higher range. Switch is at this site .
http://www.solar-electric.com/volconswit.html
Update : A CAR HEAVY DUTY RELAY WILL NOT WORK.
It will melt. Unless you are using a Bosch type relay or continuous duty relay.

 

I just checked on the internet and it looks like you probable could get away with a 24 volt Heavy Duty relay on the low voltage one but for the higher voltage one you will have to use a controller like I bought. It runs off 12 volts but its highest trigger point is 60 volts which will work for the higher voltage one . But the other thing is. Has anyone had a 22-60 volt go to dump and stop working? Maybe at the higher voltage the relay would not fry.

 

For a relay you can use a solid state relay and a zenor diode dialing in on any volatge you want. You could also use a 12v car relay as well.
Notice the input volatge on this relay 4-32VDC. That works for a steady voltage (ie battery). For varible voltages like a wind turbine use a zenor diode for a controlled voltage activation. Use a normally open relay and it will close upon your desired volatge input with the zenor diode.


25v zenor diode plus 4 volts to activate the relay................... 29v activation
55v zenor diode plus 4 volts to activate the relay ....................59v activation

12v car relay
20v zenor diode plus 9v to activate the relay...............................29v activation
Please note:
A car relay usually activates at 9 volts not always right at 12v that is why a solid state relay is better bur, you also have to know what amps are passing through the realys. The solid state relay it is more accrurate to it's rated working voltage and can be purchased in all different amp ratings as well. Always check your relay activation volatge by testing it yourself, it is not always what is says and is usually lower for a mecahnical DC relay.

Link
Solid state relays, ssr, and i/o products ...............ask for John.

 

I have fried a few 10.v-30 Sun gt's,,not to hard to fix the voltage reg capacitor with a small wire presoldered to the cap.original soldered on the bottom of the board but we can not remove board now..I have never seen over 50 volts out of the 500's and have never lost a 22-60 but have to manually add a 10-30 to get low wind output and remove it from the line when stronger winds come.

 

Can you see it the capacitor from the top? Or is it a surface mount on the bottom?
By the way Thanks Larry for the input.
Should also say electronic relays also switch alot faster than mechanical.

 

I just found the rating chart for my switch.
It is alot heavier than the one in the GTI. It melted on me and kept the contacts closed. At 12 volts it will handle 360 watts and at 48 volts it will only handle 144 watts. So if the voltage keeps going up the relay contacts will handle less and less wattage and amps. This is why I am suggesting using a Heavy Duty Relay in conjunction with the GTI. It may take it for a little while but in extended periods of dumping the turbine it will fry the relay in the GTI.
The GTI relay is only rated at 16 amps mine is rated at 30 amps .
This is the tech sheet ratings for the GTI relay.

 

Also the 250 volt rating is for the max voltage for the contacts before they produce an arc when disconnecting.

 

Tom great inoformation. You really did your homework on this, thank you.
I guess there are a few things to look at here in my opinion.

One, is if excesive dumping is occuring then the inveter to me is probally not sized properly with the turbine. Just like the scenerio with using a car PMA where it goes to overvolt to much. This means that two inverters are needed or more likely a higher voltage inverter is needed .Either way more of a load on the turbine with inveters so it does not dump as much or a bigger spread of volatge vs. amps. but there is a fine line with that on how you jack the amps to much to lose them through heat.

Second, if you are experiencing to much over volt then then external relay is the way to go if a second or upgraded inverter is not in the budget.

It sems to me a mismatched inverter system or dump load could be the key causing to have to modify the inverter dump relay.
I think it is almost necessary to use two inverters for a turbine that is rated over or in the range of 24v or higher. My wind max's are 24v and are a perfect match, the windy is 28v which might be pushing things into having to use two inverters or a higher range inverter like 1kw 22-60 or 250 10-30v with a 500 22-60v.
The higher the voltage you run the higher wind speed the PMA can take with in it's rating and the less it it will dump and when it dumps it will dump low amps. So a 500w turbine runnign at 60v should only be dumping about 8-9 amps. I think if your coils are sized wrong they will pull more amps thus frying the relay. That is why i think using the right inverter load before overvolt is critical too.

Murray and i have beeen discusing using two inverters to be used for 10 months now with a low v one in conjunction with a higer one or just a higher rated one in volts and watts to try to avoid as much over volt as possible. I have finally acieved that doing it with 3 different wattage turbines but of all the same manufacture and volt ratings. A 1kw 22-60v inverter on a 500w turbine or 750w turbine with a 10-30v 20 inverte on the front end. It seems that is the way to go to avoid any complications of more over volt occuring. Running two of the same volatge inverters in paraelle also seems to work good but heat disaption is more of a factor on the rectifies and diodes. Unfortuantly all of this experimental but what i have found is in higher winds run the turbines at a higher voltage and lowering the amps all in relation to the steepness preprogramed into these inverters and all the heat and problems seem to go away. At the end of the day i do not think most are going to want to have to modify something that they just bought. Or will they?

 

Well no doubt you two do understand the world of relays, very informative posts guys !

Picking up on some of Larry's comments on matching inverters to the turbine. Like he said long ago we decided to no longer use battery clamping and to oversize the inverters to the turbine you were using to eliminate over volt and dump loads. In the past I did experiment / test both the over volt and dump load features by running two turbines in parellel. Both features worked as advertised. BUT it was after that testing I questioned why to use them and it was from there we moved on to our different systems.
Each of my WN 500's now had two 500 w inverters each ( total of 1000) I felt this was adequate to eliminate both over volt and dump load.
Both inverters were 10.8-30 V, I would have preferred to have used a 22-60 V in parellel but used what I already owned. Another reason I was confident with this system was although the WN 500 & 750 were rated with high watts at 28 mph winds it is very doubtful either will really produce those amount of watts !
I am not saying the watts were misrepresented they weren't ! The world of wind watts change when you start adding your load which was 10.8-30 V and take into account furling ! So just using those two factors each of my 500's might have come close to the mid to high 400 watts in strong winds.
By using both those inverters in parellel I was hoping to share the work load on each.
On my 750 WN I use a Sun G 300 10.8-30 wired in parellel with a 1000 22-60 V, it also has a controlled furling mount. To date no issues with that set up.

I know most of the conversations so far have focused on volt overload and or dump load senarios but in every case I was NOT experiencing volt overloads or dump load situations, just extremely heavy winds for 2 1/2 months. My inverter failures seemed to happen if there was a power grid failure ( this should have been the island protection) or if the inverter was unplugged from the grid system. In all cases the inverter when plugged back in or when the grid resumed the inverters red light came on indicating it recognized the grid, then the first green came on with a very slight blinking BUT the turbine was braked resulting in no watts being produced.

My question to both of you now is this the same over volt / dump load relay you have been discussing that's not allowing my inverter to come back online ?

Larry I personally do not think we should have to modify these inverters , it should be a manufacturers change !
Another concern I have now is if there can be a malfunction with a relay what assurance do I have on the island protection working as advertised !

 

I have 5 gt's (22-60)in parallel and it helps keep the volts clamped and help the amprage increase. runs at about 24-25 with spike up to 40 max but only in extreme gusts..30-32 v is the usual large gust voltage...After the 40 v mark they are in constant furl here.