Sun-300G DC Input Wind or Solar Info

Discussion in 'Connecting to the Grid' started by TomT, Dec 22, 2010.

  1. TomT

    TomT WindyNation Engineer

    Thought I would post it this way so as not to get lost in other threads.
    [attachment=4:3ifsken5]Grid-Tie-Inverter-SUN-300G-.jpg[/attachment:3ifsken5][attachment=0:3ifsken5]Sun-300GDescription.jpg[/attachment:3ifsken5][attachment=3:3ifsken5]Grid tie specs.jpg[/attachment:3ifsken5][attachment=2:3ifsken5]GridTieManual 001.jpg[/attachment:3ifsken5][attachment=1:3ifsken5]GridTieManual 002.jpg[/attachment:3ifsken5][attachment=1:3ifsken5]GridTieManual 002.jpg[/attachment:3ifsken5]

    Pro: Mosfets are clamped to side of heat sink.
    Con: Bushing Fan--Will need oiled at some point.

    INFO not found in manual:
    Red LED flashes when low voltage is present. Green LED steady when seeking sync of grid. Last 2 Green LEDs cycle back and forth you are putting power in to grid. Faster means more power into grid.

    Attached Files:

  2. TomT

    TomT WindyNation Engineer

    Last 2 pictures.[attachment=1:38th0s6g]FanBushingType.JPG[/attachment:38th0s6g][attachment=0:38th0s6g]FetsonSide.JPG[/attachment:38th0s6g]

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  3. TomT

    TomT WindyNation Engineer

    Have had Grid Tie hooked up for 6 hrs and no wind with the circuit and a watt meter and what I saw on Youtube about them not using any watts with no input is right. Mine still reads 0 watts used.
  4. leamywind1

    leamywind1 WindyNation Engineer

    Thanks for the post Tom,
    Do not use these for wind. You will fry them. Only use the ones that disconnect for an overvolatge protection.
    Ther are two different kinds of these inverters.
    See my other post's
  5. murray2paddles

    murray2paddles WindyNation Engineer

    Tom's inverter does have over current protection so should kick out like ours when the volt in exceeds the 30.
    Or do you mean it might be scary not having the overload dump option ?
  6. bluejay

    bluejay WindyNation Engineer

    I dont know if I would trust those on board dumps till you look and see if the they will not fry with 300 watts of heat encased...A external dump might be safer especially if you are running multiple turbines with multiple GT's..
  7. TomT

    TomT WindyNation Engineer

    Mine did not have over voltage protection. But it had a 30 amp fuse inside.
    Also no dump load connection on it or in it.
  8. bluejay

    bluejay WindyNation Engineer

    The more I think about it.The little blades you guys fly prolly wont turn much if at all with the dump shorting them...My big blades will still turn and produce heat on a resistor if hooked to a heat dump(only 1 300w)..I bet i would fry a on board dump...
  9. murray2paddles

    murray2paddles WindyNation Engineer

    On the dump load, these units do not come with internal dumps, that must be supplied by yourself.
    Some of them come pre wired to send too an external dump load of your choice.

    Tom I misunderstood , I thought the spec you shared that states there is an over volt protection was your unit.

    Blue, I am interested in learning more from you on your blade sets ( the larger blades) in the future I would like to experiment with larger blades for both my 500 & the 750 to monitor how they preform in the low to moderate winds. If you have larger blades on any of the Windy turbines right now, can you let us know where you purchased from, the cost and the lengths and if you purchased hubs with those blades, do the hubs match the shaft size of the Windy ?
  10. leamywind1

    leamywind1 WindyNation Engineer

    Hi guy's
    Sorry it is a long explination but i tried to cover it all.
    I wanted to post some information on my findings with these inverters and maybe answer some questions:

    Grid tie inverters:
    There a 3 types of grid tie inverters non UL that are selling on e-bay that we are all going ape sh#@ for.
    The first famous one is made by Power Junk oh I mean Power jack or any other that says solar and wind. These are strickly for solar only. Why? Because they do not have an overvolatge protection system buil in. They are rated for a constant volatge window in the specific range of the inverter reagrding their internal 20 amp fuse as well. At the least you will blow out the capacitors inside. Do not use these for a wind turbines.

    The second one is made by Sun G who also has a solar inverter. Again made for solar only even though it might say solar and wind. These sun g's are a good product for a solar panel. They seem to be more efficant then the others that are non UL approved-e-bay type.

    The third is the 500w SUN G grid tie inverter with a dump load and over voltage protection system. Has a voltage input of 10-30v or a second inverter of 22-60V w/ a 40amp car fuse. Each of them disconnect from the wind turbine at their higher voltage ratings. Ranging from 300 watts to 1000watts although I have herd there are problems with the 1kw units as of now. You can buy them with or without the built in rectifiers. I recommend a unit without the buit in rectifier if you plan on adding more turbines. You will only be able to paraelle the inverter not the turbines with out going thru hell or more confusion. Get the ones that say D/C not A/C. A/C has the rectifiers built in. Paraelling the positive and negative of your own rectifier is a better option. Please read before you buy one.

    This is the inverter of choice as far as i have fouind for a wind turbine if you are going to use a non UL inverter. If you are trying to supplement your electriicty with wind power and NOT sell it back to the utility this is the inverter for micro wind in the 1kw range. If you want to sell back to the utility and get Renewable Energy credits then you need a UL approved inverter, inspections and permits. Windy boy inverter, ect.
    These REC credit are listed on for your state.
    Remember a UL inverter requires a higher voltage to start which means a higher wind speed. Even Ginlong does not start until 30v. Although maybe a 48v turbine will produce watts at 30v in 6-8MPH winds. Not shure on that.
    Use a 24v turbine or higher a 12v system does not give you many choices. 24v or 48v turbine will hit a power production of watts in a lower wind speed then a 12volt. So if you are using batteries try to stay in the 24-48v range.

    The Sun G has a dump load system. It is a built in relay the turns on when the turbine disconnects at the rated higher voltage of 30v or 60v. You supply the external dump load resistor what ever that may be. There are two terminals externally on the inverter to hook up the dump load resistor to. Obviously you would not hook up a 1kw dump load to a 300 watt or 500w inverter. size tour inverter and dump load to your wattage of your turbine and beyond.
    I am only speaking of grid tie with no batteries. Although you can use batteries if you would like for the dump load or
    batteries for a volatge clamp with a diode. I know there are many other ways using contactors, relays capacitors, ect but lets keep it simple for the new guy's just getting started. I know right about now you wheels are turning for the more savoy

    If you have a 750w turbine you would not connect up a 300 w grid tie inverter to it unless you want to just give your money away. In that case please send the money to You would want to connect up two 500w inverters using the dump load controll system. This way the inverters if using two (500w ea) for a total of 1000w, both disconnect at the rated higher volatge at the same time and will go to the rated dump load you have installed. Your dump load resistor should be about 20% more then the rated turbine. Watts is watts so, if you are running bigger blades this 20% will alllow for a more torque issue from the bigger blades for a 750 w turbine. What I have found is using a 10-30v inverter works very well as i get 10-30 watts in about 6-7MPH winds. As the wind, volts and amps increase the other 22-60v inverters take over on the back side of the higher winds.
    Sizing your inverter takes some experimenting since all turbines are different. I am using 24v turbines so for me I get low wind production and high wind production 10-30 and 22-60V. My dump load is on the end of my 60V inverters. Each inverter has it's rated dump load and all inverters are connected in paraelle to my turbines as all of my trubines are in paraelle all after the rectifiers whick I am boosting my amps not my volts. The first one at 10-30v disconnects and the other 22-60v handle the high winds until 60V, then dump. I am currently trying to work out for my turbines which and how many inverters I need to not dump as much but convert more electricty into my home. As the wind pushes harder the inverters make more so in my case maybe (1) 10-30v inverter for low wind and (3-4) 22-60v inverters for the high winds as I have 4 turbines. All inverters joining in at 22v-29v, at 30 v the first one lets go-overvolatge protection and the other x amount take over from there. If you have mulitple turbines you can do one system per turbine or one big system as I am. All of this is monitored by a watts view meter. Via usb to my computer with a dash board display. See the other post's on that monitoring system

    Now the key is not to have a car alternator, tread mill motor or any POS PMA that needs 2000 rpm to get 10 amps out of it. You have to be realalistic of what you are buying. I know it is hard because most of the guy's selling these PMA's do not know SH@# about them. Their claims are their sales pitch and most of their claims are very bogus.
    Most of our locations for wind may be fine but we all do not get 1000 watts out of our turbines all of the time. How many times do you really see 30MPH+ winds? If you see that kind of wind more then 150 times a year you need to get out of the micro wind and get yourself a 10kw turbine or bigger and send us all some pictures and data. So for a reality check the 10-30v inverter is a good choice since most of the time we will see 10- 100watts in 6-12MPH. So I feel it is better to get something out of the turbine then nothing. That something using the 10-30v inverter could be the difference of your turbine making power throughout the year or only when the winter winds come. My choice is to make power throughout the year but be prepared for the higher winds when they show up. Remeber all turbines are tested in perfect conditons. Is your site perfect? Probally not for 90% of us. Most people that do a vid and show a turbine making 1000w are getting 35MPH winds and they do not show you the trees or any other obstruction or tricks they have up their sleves. So again starting off with a 10-30v in my opion is a good start. You then have to see where your turbine is in volts and watts before that one disconnects. This will determin you next choice of inverter. May be you have a 500 w and two 10-30v is all you need with a 500w dump load. Some experimenting required. All in all it does not have to be so difficult with using so many components and more stuff that can fry or is just not needed.What about if the grid goes down. These types of inverters work off of the utilty power so if it does go down the dump load will not work. Simply add a relay system N/O-N/C a/c 120v so when it does, the power gets diverted to a bat bank or dump load. That is one of the features of my control system. I hear your wheels turning

    If you are not savoy with the electrical connections then talk to a certified electrician which I am. No I am not an electronics guru but i may be able to help. Here is some free information on the A/C electric. Do not hook these upto a GFCI or GFI that is a myth as I have tried this just to see. When the inverter puts out the higher wattages it will trip the GFCI and shut your inverter down. A GFCI is not made for incomming power or "backfeeding".
    There are electronics in it and they can easily be fried with backfeeding, I do not have them in my control systems. You can research that on line. Who ever tells you that you can, is WRONG. Look in the NEC code book too.
    You system should have a dedicated line from your electrical box to your inverter. Just plugging it into the wall is not the right wat to do any renewable energy system. I do not care what the seller of the inveter tells you, they are in the selling busn. Not the electrical busn.

    The inverters work off of high amps not real high voltages. So if you can get 50v at 20 amps out of your turbine and the turbine is rated at a 1000w using two 22-50v inverters may work better for you. Maybe 25v at 40amps using two 10-30v may work for you. Maybe (1) 10-30v and two 22-60v may work for you. But either way with a few inverters and some experimenting and maybe a relay that should be all you need considering you have wind and a decent turbine-PMA like the windy nation or a wind max type turbine where it is made for wind and not a car.
    If you have the Swea inverters for your turbine and you are looking to get more production in lower wind you may want to try incorporating a 10-30v sun G inverter in paraelle with your Swea system. This will allow a lower wind speed production of watts now starting at 10.8v instead of 20-22v.

    I hope this sheds some light on what these inverters can do as well aswhat i have found for my installation. I do relize that this might not work for all of you. So again some experimenting is required, that is the fun of it but keeping the cost reasoanble and a more constant power production is key. Wind is very tricky and that is why i am hear as well, to learn and find the free wind watts.
  11. murray2paddles

    murray2paddles WindyNation Engineer

    One turbine testing.

    Larry is doing the multi turbine testing and I am doing the single turbine testing and we share our info everyday so that someday we can share with everyone ,, this is what we have found that works the best.. :D His results are way ahead of mine so far but I think he is stealing my wind :lol: By sharing information I have been learning LOTS from him.

    On the Power Jack,, it is a good inverter but I agree with Larry , for safety it would be better suited for solar because of no over volt disconnect and no internal connections to dump. BUT if you already own one, you can use it on the top end of your turbine. My Power Jack is a 1200 DC inverter, I am using an SWEA, AP box and one of their dump loads and believe me it has stood the test of some of the most violent winds I have experienced. I have been very pleased with it but it is all depending on how well the SWEA Volt control and dump hold out.
    Don't forget my observations are because I am testing the hook up of only one turbine with multi inverters.

    On the font end to go partners with the Power Jack is the Sun 500 DC with over volt protection and ( an internal dump option if you chose to use it). You must supply the coils or what ever you choose as your dump.
    After testing the turbine in this way my next options will be adding one more Sun 500 to the front end of this turbine to test if all it requires is two Sun 10-30 connected parallel with a dump load and no top end inverter. We want to find out if we can max these turbines out by just taking from the front end low volts and low winds.

    I did trade my Sun 500 in for a DC model just to allow more options later on, or I should say when I move it for testing over to my 750 and i know I will eventually end up combining a Windy 500 & 750 to run as one.

    I know the 750 can produce in high Winds, I will attach a few photos of watts produced in a wind 20 - 28. using SWEA inverters. I would really like to clamp down the front end of the 750 to see what combined watts might be available from 2 or 3 Sun 500 10-30, and leave my SWEA on the top end for over volts, high volts.

    For two years my turbines that are hooked up to high Volt inverters, (28) ( 20) - 55 Volt, have been spinning in 6 to 15 mph winds and never giving a watt back to use. Since combining the low wind 10 - 30 volt inverters watts are being produced starting from the 6 - 8 mph winds. At last what I have been looking for.

    I have been vocal in the past about power curves ranging from the 5 - 30 mph range. The 25 - 35 mph gives impressive results but what I have been hoping to raise discussions on is the fact that I might only see those high winds a hand-full of times per year, so really they are meaningless to me. i need a system that pays me back in the low to moderate winds. For the first time I think we are getting so close to understanding and being successful with results !

    I am also very close to changing over to testing larger blades to create more low end torque as i am not concerned with the really high rpm created by the shorter blades.. all in good time I guess.. what I really need to learn is some patience and not try or want to do it all at once :roll:
  12. murray2paddles

    murray2paddles WindyNation Engineer

    Whoops, forgot to attach the watt photos. lol

    wind speed in the 20 - 28 mph range, 750 windy into SWEA inverters

    Did see some higher but I was way to slow in taking the photo

    [attachment=2:v3odh9wy]750 watt 2.jpg[/attachment:v3odh9wy]
    [attachment=1:v3odh9wy]750 watt 3.jpg[/attachment:v3odh9wy]
    [attachment=0:v3odh9wy]750 watt.jpg[/attachment:v3odh9wy]

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