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Forum Index : Solar : Giandel ??
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| petect Newbie  Joined: 03/02/2018 Location: United StatesPosts: 15 |
Hi All There is a guy on youtube who puts together some low cost pv systems (he also has a website). He uses some components from a company called Giandel that operates in Australia. Does anyone know anything about Giandel? I’m mostly interested in the quality of their products and how well the company stands behind them. This is the build that caught my eye. https://www.mobile-solarpower.com/2000-watt-24v-solar-system.html The Giandel web site. https://www.giandel.com.au/ Thanks in advance. Pete |
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renewableMark Guru  Joined: 09/12/2017 Location: AustraliaPosts: 1678 |
I bought one for my caravan. It was a 2800w continuous model. Used it about 5 or 6 times. One morning with the battery around 13.2v (12v unit) I put the 800w toaster on, the unit went bang. 400 ah of battery, so there should have been plenty there for an 800w load. Have previously run a toaster and even a small welder off it before. Had a look inside and it uses out of date mosfets that you can't buy anymore. Some resistors inside were arranged very unusually. They mustn't have had the correct parts so they had put two resistors in series and just wound the ends together (no solder) with them sticking up in the air. Warranty was 12 months and mine was 14 months old. I emailed them to see what they would say, they said it's out of warranty and I could buy another one at 20% off or pay for repairs. These are the mosfets it used. Cheers Caveman Mark Off grid eastern Melb |
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| petect Newbie Joined: 03/02/2018 Location: United StatesPosts: 15 |
Thanks Mark. Much better to find out from you than to shell out the $$$ and learn that way. Pete |
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| Warpspeed Guru Joined: 09/08/2007 Location: AustraliaPosts: 4406 |
I had never heard of Giandel until Mark dropped his dead inverter in here for me to look at. Its the crappy high frequency type that uses five small dc to dc converters in parallel to generate several hundred volts of dc, and than turns that into a modified sine wave. Its all very highly stressed with light duty parts, and just looking at it the advertised power rating is just a complete total joke. Never had one of these in my hands before, but have read plenty of horror stories on the internet about these types of high frequency inverters and how they are rather fragile and very prone to blowing up. Not necessarily Giandel, but high frequency inverters in general are definitely best avoided. Much better are the larger transformer inverters, even the modified sinewave types. Better still are the PWM pure sine wave transformer inverters, but all that "goodness" comes at very great extra cost, size, and weight. Cheers, Tony. |
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LadyN Guru Joined: 26/01/2019 Location: United StatesPosts: 408 |
like the Warpverter? What other PWM pure sine wave transformer inverters are there? (the other one I think is the sPWM based one like OzInverter but that's fairly higher freq. than the Warpverter AFAIK) |
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| renewableMark Guru Joined: 09/12/2017 Location: AustraliaPosts: 1678 |
LOL I thought you would get a good laugh out of that. Did you like the way they did the resistors? I soldered and put shrinktube on them, it wasn't like that when I got it. Even a knucklehead like me can see it's crap inside. I was going to toss it in the bin but thought since I was popping by may as well have you look at it, there might be some bits you could re-purpose. Cheers Caveman Mark Off grid eastern Melb |
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| Warpspeed Guru Joined: 09/08/2007 Location: AustraliaPosts: 4406 |
Natasha, There is a sort of natural pecking order between total crap and "solid as a rock". High frequency inverters are the lowest of the low, cheap and nasty Chinese, typically. Transformer inverters have vastly better transient overload capability, and are far more robust. The Oz inverters are KING OF THE MOUNTAIN but many people have had frequent blow ups trying to get home brew versions up and running. Mark is a battle scarred hero, but by golly he is still game and will get there eventually for sure. Now the Warp Inverter is a little bit different in that it uses far more parts and requires a lot more work in winding multiple transformers. But its simple (like a brick wall or chain link fence is simple). But many people look at a brick wall and say OMG all those bricks, vast numbers of bricks, all that complexity, all that work laying all those bricks !!! I would rather build a PWM inverter because it "looks" a lot simpler, cheaper to build, with far fewer parts. And after they have rebuilt it after numerous explosions and fires ten times and spent a fortune on mosfets and burned parts, after about a year of trying, they still claim it is simpler, cheaper and uses fewer parts. What makes the warp Inverter idea so robust is that it switches at a very low frequency, and the physical layout is vastly less critical. It will take longer to build but once built it will GO ! Cheers, Tony. |
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| renewableMark Guru Joined: 09/12/2017 Location: AustraliaPosts: 1678 |
LOL there is a long story there and I finally traced it down to faulty 8010's, but that is for another thread. Cheers Caveman Mark Off grid eastern Melb |
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| LadyN Guru Joined: 26/01/2019 Location: United StatesPosts: 408 |
Mark, you're talking about the OzInverter and not the Giandel here. Correct? Why is that though? The physics is there - high frequency does allow smaller inductors and that lead to cost savings. Nothing wrong with that. The primary reason why I love the warpverter is because I only know high school math while high frequency design requires advanced calculus, bode plots, PCB layout and the like. There is much less margin to be ignorant when doing high frequency The Chinese are not want of education or advanced calculus, so what's the issue? I think the added thermal mass afforded by bigger transformers helps? But physics does not care how energy gets transferred. It might destroy a few MOSFETS along the way if the engineer forgot to account for driver impedance in a high dv/dt situation while not compensating for Cds, but if the engineer did her job properly, physics will hum along fine. Just to abate any confusion, let me call the "PWM inverter" as Ozinverter. The Warp Inverter, from what I understand uses 50% DC square waves and DDS, I think. By changing the DC, it could be possible to change the number of output stages needed to get a sine wave, but that's all my ignorance and blind hope talking. First, I must of course understand how the Warp Inverter works before embarassing myself further. So with my ignorance, I would argue the Warp Inverter is a "PWM inverter" too. It just uses a fixed DC. Atleast for now Anyways, how does Ozinverter use fewer parts than the Warp Inverter? If talking solely about the count of transformers, sure. From a pure parts count perspective the Warp Inverter uses a few tens of parts (power diode OR, control board, driver board) while the Ozinverter uses a total of thousands. If I am able to pull it off, the Warp Inverter control board can even shrink down to a $2 STM32! Maybe that's impossible and I am just completely ignorant of what is going on and what needs to be done. The Ozinverter is beautifully optimized to a low total cost. If it's built properly, it has a phenomenal ROI. I do not hope to understand the details of a Ozinverter because I lack the knowledge. The Warp Inverter seems like a fair compromise for me. It limits the price I have to pay for my ignorance. Where am I mistaken? |
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| Warpspeed Guru Joined: 09/08/2007 Location: AustraliaPosts: 4406 |
A high frequency inverter takes some low voltage dc (12v for Mark's Giandel) and generates high voltage dc, usually about 340 volts. It does that with a high frequency switching supply, the Giandel runs about 40Khz, all fairly typical. Now that is the problem right there. If your switching power supply is designed to deliver 1Kw of power, that is its maximum. It cannot suddenly supply a peak power of 1.1Kw, or 3Kw or 5Kw for a second or two. Many loads, in fact most loads have high inrush currents when initially switched on, and a high frequency inverter has absolutely zero short term overload capacity, despite what it claims on the front of the inverter. So you take your 99,000 watt inverter that has a surge capacity of a gazillion watts and plug in one of your power tools pull the trigger, and the smoke escapes from the inverter. Happens all the time... Now a transformer inverter has a vastly higher overload capacity. It has multiple huge mosfets to ensure low conduction losses, but that also provide massive short term overload capacity. The large transformer and heatsinks can absorb a lot of flash heat, so the inverter will not complain too much about short term overloads. Now a tiny high freqency switching power supply will have much smaller parts, and just cannot absorb the same type of short term overloads without going bang. Much more stressed, far more fragile. Just a toy really, and best avoided for serious usage. The Warp inverter has all the advantages of a good PWM transformer inverter as regards short term overload capacity, and as said above, its really a kind of pulse width modulation at 50Hz. The big advantage is all of the switching is done at a very low switching frequency (not at 23Khz) and that makes a great many things far less critical. PWM has to be designed and built exactly right or there can be endless strife. All those troubles can be avoided, but with the disadvantages of requiring three or four inverters instead of just one. The extra transformers and switching devices make it uncompetitive commercially except at very high power levels, which is why its not a common way to build an inverter. Cheers, Tony. |
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