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Steve / Re: My Scratch Pad
« Last post by MadScientist267 on Today at 09:51:39 AM »
Steve / Re: My Scratch Pad
« Last post by MadScientist267 on Today at 01:13:26 AM »
Steve / Re: My Scratch Pad
« Last post by MadScientist267 on Today at 12:54:14 AM »
Automation, Controls, Inverters, MPPT, etc / Re: PowerJack LF-10k 48v issues.
« Last post by DJ on Yesterday at 10:27:13 AM »

I love the ratings on some of those packs. Some are supposed to be over 50 Ah!
Sellers, particularly ebay merchants just seem to put whatever impressive number they dream up on things and any relevance to reality is out the window.

I have bought 3 Different types of Light bars now and they are all ridiculous ratings.  The last lot was supposed to be 210W and turned out to be 32.
The sellers always try to bull$#!+ and bluff their way out of a refund or return demanding to know what your qualifications are but I mearely ask what theirs are in order to be able to judge whether mine are adequate or not. Soon shuts them up. I got the feeling the last one really didn't know his arse from his elbow and the fact it had 210W on the box made it 210W and he had no clue as to how it could be different.

I have emailed every seller before purchase to confirm the lights are rated at what they say. Some I don't hear back from so I know what that means but the others have assured me they are as rated on the box which is why I purchased them.

So far all have refunded either partially or in full.  One guy went on and on about me trying to rip him off by doing an ebay complaint who charged the item back but no matter how many times I pointed out he was ripping people off by knowingly still selling scam products, I was still of course the bad guy.
Should have bought 20 of the things and had them all charged back.

Another one I see is fantasy ratings on 18650 batteries. Some of these sellers have batteries with capacity's 4-5 times what the top manufacturers are claiming.  Best I have seen so far is a 1500Mah 18650. I'm led to believe the best " genuine" cells atm are under 3000 mah. 

Over rating goes a long way back. I remember asking an audiophile acquaintance what the PMPO rating on sound equipment was about 20 years ago. I said sarcastically that  given some of the numbers I had seen on small portable units, it must be a measure of what the board will take when hooked to a HV transmission line before it vaporises a millisecond later.  He looked at me and he said that's pretty much about what it is!
I also asked why my Harmon Kardon Amplifier was only rated at 35W but would near take the windows out the house but friends other brand units were rated at 100W and were no where near as powerful. He said it depended what they measured the total harmonic distortion at. He Said HK measured theirs very low where others might be at 10%. If rated to the same scale as the HK, their rating might only be 10W.

I also got caught with inverter. Totally fictitious ratings on those as well.  One real giveaway is look at the fuse rating. On 12V units I take the rounded number as 10 for the multiplication factor for the output for 12/ 240V units.  This allows for different efficiency, different battery voltages, output voltages ( 220-250)  etc.  Therefore if the unit is 1000W output, it's going to be ( at least) 100A in. If the thing only has 2 x20A fuses, you know it's BS and you are going to be lucky to get 500W out the thing.  I see a lot like that. Huge ratings but the 12V in fuses are a fraction of the multiplied output.

All depends how you want to screw and distort the numbers.  :0(
Oztules / Re: testing the egs002 inverter board
« Last post by oztules on Yesterday at 05:31:50 AM »
The egs002 or the 8010 circuits can use the transformer to make an inverter... but not a ups I'm afraid.
Oztules / Re: testing the egs002 inverter board
« Last post by NJM on Yesterday at 03:42:20 AM »
Hi to all i  have a Italian made onpower ups,  i made a mistake and the board control burnt. I would like to know if is possible use it as a power inverter puting a EGS 002.  The ups is very good staf it uses a toroidal transformer thats why itryng to keep it.If enybody has any idea  how to keep it working. Please help me. Thank you  to all in advance. Njm.
Wind and Hydro / Finally - 11' Motor Conversion Flying
« Last post by Dave B. on Yesterday at 01:08:04 AM »
I built this 3 phase 48 volt motor conversion quite some time ago (see classifieds post custom alternators) and finally completed the wind turbine. Tops out at about 300 lbs. 90' up and as alwys now waiting for decent wind for testing. Comercial slip ring assembly, manual and electric braking, custom controller with redundant auto shutdown. Supplimenting 7kw voltaic charging 1110 AH 48 volt LA  L-16's. As the days grow shorter and Fall and Winter winds pick up I plan for this to be very helpful. Updates to follow. Dave B.

Oztules / Re: Using old grid tie inverters to charge batteries
« Last post by oztules on July 25, 2017, 07:48:30 PM »
yes.... I actually use the lm339 version for 12v regulators on electric fence solar installations... they will be gradually changed to the arduino I think.

I will have to do another article to explain the wiring/hooking up of all of this I guess.

My main charger is one of the 339 boards driving 6-8 hy4008 fets at up to 100-150 amps or so @ 60v.... very cheap alternative.
I will chop the 339 parts off and replace with the arduino too.

Automation, Controls, Inverters, MPPT, etc / Re: PowerJack LF-10k 48v issues.
« Last post by lighthunter on July 25, 2017, 06:19:20 PM »
Lithium battery jumper packs same way. I purchased a pack 2 yrs ago boasting 12 AH capacity. I got it home and charged up, threw it on msw inverter running a 100w incandescant. turned out to be a 4 AH capacity. I kept it as there were no comparable units for $30 so i figured i still got a good deal. Ive used it a lot and though still going strong i thought it b great to buy a backup lipoly battery for it to b ready when it goes. I was surprised to find given the dimension specs of original, 130mm x 45mm x 25mm. I could not find a replacement inside those dimensions with greater than 4 AH capacity and i was looking among the high quality choices to fill the spot.

That said, the 4AH actal capacity of a labeled 12000mah battery of that physical size was not the fault of an underperforming/defective, or inferior battery. It was simply the fault of the sales literature.
Its unfortunate that merchants do that and weve seen it among many electric devices including the pure sine inverter in this thread. If you know about these shortcomings up front and usually by experience you do, one can still come away with a decent purchase just not one that matches the label. Of course if you have a critical application where spec must be accurate then do as you said.   :)
Oztules / Re: Using old grid tie inverters to charge batteries
« Last post by Pete on July 25, 2017, 05:32:45 PM »
Hi Oz, I am a keep it simple type myself, just wondering if your PWM board would work just driving a couple of Mosfets as a regulator.
I have three regulators in parallel at the moment because they are much cheaper in low current versions than high current.
I was thinking that rather than run a GTinverter to charge my batteries I may be able to use the program you wrote to run an arduino based 12 volt regulator.
Or is there an easier way.
I guess your battery charger setup works good in that you don't need large cables from the panels to the batteries, and you have lots of GTI's sitting about wanting to be used. Like you said , you enjoy making problems so that you can sort them out.
I am just looking for a simple, easy to make, cheap, regulator.
Thanks for the articles, I really enjoy reading of the exploits on Flinders
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