600W 10-60V to 12-80V converter

[Cheeseboy]

http://www.yoybuy.com/en/show/18327288810/?cate=search

Through taobao agent ^

http://item.taobao.com/item.htm?spm=2013.1.0.115&scm=1007.77.0.0&id=18327288810&ad_id=&am_id=&cm_id=&pm_id=

^ original taobao link

This converter is more conservatively rated, note: "maximum power 800watts"

Input voltage limited between 10-16v however. Perfect for server power supplies, saves me the danger/trouble of hooking them up in series for 24v.

also has good stuff like quiescent current rating <50mA

however a fixed output voltage of 60v is kind of useless, The seller has exactly the same board with different output voltages so it must be a resistor value or the like to change voltage.

Custom voltages can be built but there is a minimum order quantity of 5 units.

Ah well.

 

[cwah]

That is nice. Who's your taobao agent? I may ask one too lol.

Best would be to have an adjustable potentiometer directly on the converter. I have several battery set-up between 67V to 104V lol. But I can also accomodate multiples converter, but 1 or 2 adjustable one would be the best.

 

[Cheeseboy]

I am trying http://en-taobao.com/ just sent an order request, and am waiting for a reply. There seem to be no perfect agents, so there's a degree of luck involved.

 

[cwah]

Thanks cheesyboy, going to contact them to see if they can help me

 

[Cheeseboy]

My purchase is going well so far. Buying 3 units, I am required to pay around $47 now, then international shipping later. I don't think i'm going to save anything really ahahaha...

Price from Ebay would be 72 dollars, so we'll see whether the hassle ends up worth it!

 

[cwah]

I had the answer from my agent. Apparently the 60V converter isn't available.

 

[Cheeseboy]

http://item.taobao.com/item.htm?spm=a230r.1.10.173&id=19276664616

here is an alternate taobao supplier, if you ask them to buy this one they should be able to. I got the all clear from mine... So hopefully they are not messing with me

are you using the same agent as I?

Oh to clear things up, I am purchasing the original converter of the thread, as plug and play voltage/current adjust is way easier...

 

[cwah]

Are you finally buying the same item as mine?
http://www.ebay.co.uk/itm/170893208817?ru=http%3A%2F%2Fwww.ebay.co.uk%2Fsch%2Fi.html%3F_sacat%3D0%26_nkw%3D170893208817%26_rdc%3D1#ht_8211wt_1326

So the final price is not very different from what I've paid I suppose? I purchased 5 and paid 22$ each.

 

[Cheeseboy]

Yeah it's pretty similar.

But also, I just bought a 48v 3kw server supply! So these can be used at full 600 Watts! the supply cost 50 dollars, so 1.8kw of charging power isn't bad for 120 dollars!

 

[cwah]

3KW?? lol

But are you going to put them in parallel? Have you checked if it's possible for non-isolated converter?

 

[Cheeseboy]

A supply doesn't need to be isolated for running in parallel, only for running in series. Someone correct me but I am 99% sure, and sure enough to hook it up that way without doubting myself.

Yeah the 3kw supply is 48v 57A or something, costs <$50 on ebay if you want to find one. Although I believe they only work on 240v input. It'll be a nice change from the 150watts I charge with now :lol:

 

[cwah]

I've read that you need to take some caution when wiring in parallel because one of the converter may get all the load while the other is doing nothing.

If there's anyone that knows how to safely parallel them I'm keen to hear

 

[Cheeseboy]

I have a link bookmarked at home which shows how to ensure the load is equally shared by using load resistors.

I'll edit this post to include the link when I get home.

 

[cwah]

I received it today.

It is actually huuuge compared to the previous 12-60V DC-DC converter I received:

They didn't lie about the weight:

Cooling is passive and is done via wiring to the heat sink:

Minimum voltage is 12V as advertised (with a 12V power supply):

But I've noticed that the voltage can go beyond 90V

I double checked that with my voltmeter and it can indeed go over that. I didn't keep turning the voltage trim pot but it is possible to go beyond this 91V displayed here.

I'm going to check with the seller to see if I can safely charge over 80V.

Could be a nice little universal converter

 

[IBScootn]

Interested in how much current it could provide at 90V.

 

[Cheeseboy]

The maximum voltage rating of the input caps is normally a good indicator of the upper limit.

I lost the guide for paralleling power supplies, am looking for it again.

 

[cwah]

I contacted the seller, apparently, even if it's possible, it's not safe or reliable to charge over 80V.

However, if we buy more than 100 items, they can custom the converter for us and make it work over 100V.

Anyone interested?

 

[Cheeseboy]

ahaha 100? pretty high.

Did he mention what kind of discount it would be?

Definitely cheaper through Taobao at those quantities. much much cheaper!

 

[cwah]

I asked him, but I don't think we would have discount as it would be custom made for our needs.

I asked for higher input limit such as 25-30A

 

[cwah]

Yeah, we can either go through Taobao or directly mention him the taobao link to lower the price. I think he is in direct contact with the manufacturer so it should be possible to negociate that.

He said it's possible to go over 100V and 25-30A. What other personnalisation would be interesting? I suppose a lot of member from endlesspehere may be interested by such module. It's tought to find a 100V+ charger

 

[cwah]

First review of the DC-DC converter here:
[youtube]snRHTsjxN_Q[/youtube]

Blue wattmeter is the voltage from the 12V 500W ATX power supply.
Red wattmeter is the voltage to the 20s lipo battery.

A strange noise is starting from 6A onward. I don't know what is it. The noise is similar to the one I have on my hyperion.

At 10A, it can pull around 85W (the blue wattmeter is a over-rated). So I'd say around 75% efficiency.

Noiseless is however be around 6A, at around 50W output. Still around 75% efficiency.

 

[cwah]

I've just remembered that it should be able to accept up to 15A input. So I tried to increase the input:
[youtube]SrkhLOnz16w[/youtube]

From 12A onward, it completely saturate and there isn't any more power out of it... :?

 

[heathyoung]

Not suprising considering the size of that inductor. A non-isolated boost converter of a few hundred watts isn't that hard to come up with, you just need the right magnetics and silicon.

Consider the power supplies in car amplifiers - some of those are quite high voltage rails +/-50V @ 300W+ AND isolated.

 

[cwah]

Is the noise normal?

I purchased 5 of them with a lot of hope...

I tried on another one and was able to pull 15A input... but it only has an output of 110W max. So It's around 60% efficiency with this horrible noise on the video.


Is it safe to leave this noise? I'm always afraid that it's going to blow.

 

[ZOMGVTEK]

These things look quite good if you believe the specs. I doubt they would be too happy with a few in parallel, but for lower power stuff they might be great if they hold CCCV well enough.

cwah, that audible noise showing up at higher power tends to mean the supply is unstable. It's probably going to be less than reliable.

I'd like to see the output loaded with a CC electronic load at the limit of this DC-DC, and then sweep the input voltage to check for instability and efficiency at various input voltages.