Jan 08, 2012, 03:09 PM Steven United States, CT, East Hartford Joined May 2010 504 Posts Hey Bubba Gump, What's the maximum voltage that you are looking for? It's even possible to run 3 powers supplies from this forum in series to reach 30V - 36v. Also, http://www.rcgroups.com/forums/showp...postcount=1031
Jan 08, 2012, 04:12 PM
Southern Pride
Haralson County GA. USA
Joined Oct 2004
35,074 Posts
He mentioned Power Lab so max. is 32V but unless he really needs every single watt available 24-25V should be fine.

FMA online power calculators.

Snip

Quote:
 Question 3 What are the minimum power supply specifications that will enable me to take full advantage of PowerLab 8 v2's full power capabilities? Answer: Power Supply Voltage (V) 26.35 (PowerLab 8 v2 will accept up to 32V input, but power is not improved above 30V input) Power Supply Current (A) 60 (Power supply output current capability can exceed 40A, but power will not be improved)

Charles
 Jan 08, 2012, 04:23 PM RC Helicopter Pilot United States, CA, Westminster Joined Mar 2010 1,696 Posts Actually the PL6 is a different beast than the PL8. It requires 30V for max output. And maximum input is 32V.
 Jan 08, 2012, 04:34 PM F3P, Slap, IMAC, Helis Joined Jun 2007 286 Posts Yea thats what i was looking at was the powerlabs problem is running 3 in series is that 35v max for the powerlabs is 32 so you would have to use a voltage step down. whats the best way to do that.
Jan 08, 2012, 06:02 PM
Southern Pride
Haralson County GA. USA
Joined Oct 2004
35,074 Posts
PL6 calculator here

http://www.revolectrix.com/pl6_calcu...PL6_Calc_1.htm

Yes 30V for max. of 40A output into a 6S however with only 24V input output is still 32.4 Amps.

32.4 / 40 = 81% of max. output available.

Charging a 5S output would be 38.9Amps.

Which is why I posted

Quote:
 He mentioned Power Lab so max. is 32V but unless he really needs every single watt available 24-25V should be fine.

In most real world applications there will be very little difference in charging times.

I have often posted that what a charger can output with voltages other than 12,24 or 36V does not really concern me as those are the more common voltages available from 12V Pb batteries in series.

I got into to rather heated debates on another user's forum over the output from the FMA CP10 as on 12V it was well below it's rated max. which required 16V which to me is really not common at all.

Charles
Last edited by everydayflyer; Jan 08, 2012 at 06:12 PM.
 Jan 08, 2012, 06:12 PM F3P, Slap, IMAC, Helis Joined Jun 2007 286 Posts yea i know that but would rather use its full power. FLying 12s electric helis is were you need the max charge rating. so i need to get the full 40a output. I have a super dou but its so big i hate it thats why i like the pl6 casue its small.
 Jan 08, 2012, 07:24 PM Steven United States, CT, East Hartford Joined May 2010 504 Posts Hey Bubba, Usually any power supply with an internal trim pot that adjusts output voltage can easily be modded to drop the voltage to below 10v if the UVP allows it. Also, any voltage greater than the +V DC output applied to the 12V RMT SENSE line will allow the output DC voltage to be reduced to under 10v. This just fools the PS into thinking the output voltage is higher than it is, so in return it will drop the output voltage. This can be accomplished when running power supplies in series. From what I gather, any PS with more than around 50A is not needed when running them in series for charging. The PE 6800 PS would be overkill. The Delta DPS-700EB or IBM xSeries x336 585w power supplies may be good for what you need. I'll do some testing tonight and post results tomorrow.
Jan 08, 2012, 07:37 PM
Steven
United States, CT, East Hartford
Joined May 2010
504 Posts
IBM xSeries x336, AcBel API3FS25 585w (48A 12.2V) PS enable

IBM xSeries x336, AcBel API3FS25 585w PS enable.

Connect A8 and A10 to power up.
Connect (B4 to +12v) or (B7 to ground) with potentiometer
to adjust output voltage up to around 14v. Use the set that works best.
Best to set internal trimpot to highest output voltage when using external voltage adjustment pot.

Connect B7 directly to +12v to stabilize output voltage if needed.

OCP (Overcurrent Protection) can be adjusted with trim pot from the original 50A up to 70A. Use with caution!!

A1 = Current Share
B4 = 12v remote sense return
B7 = 12v remote sense

# Images

Last edited by xandrios; May 14, 2012 at 08:26 PM.
 Jan 09, 2012, 11:02 AM F3P, Slap, IMAC, Helis Joined Jun 2007 286 Posts see you cant get 15v out of it you need 15v then put them in series to get the max wattage on the charger 40amps. Is the there a pot on the dl580s the smaller ones, 74 amp ones.
 Jan 09, 2012, 11:51 AM F3P, Slap, IMAC, Helis Joined Jun 2007 286 Posts so your saying i can put three power supplies in series that have a voltage pot to adjust the voltage. and then turn one of them down so get the 30-32v i would need to max out the the charger capablity.
Jan 09, 2012, 05:24 PM
Steven
United States, CT, East Hartford
Joined May 2010
504 Posts
Hey Bubba Gump,

you can use this mod to allow running 3 IBM
xSeries x336 585w PSs in series for the 30v - 32v you need.
After adding the resistor, the adjustable voltage range will be from 8.5v to 12.5v.
Set the voltage to around 10.5v
for each power supply using the voltage control pot.
That should give around 31.5v in total.
Voltage drop with a 60A load will yield 31.2v.
Be sure to tie the 12v remote sense to the +V and the 12v remote sense return to ground on each power supply.

You can turn the OCP adjustment pot a quarter clockwise to increase OCP to 60A since we are running at a lower voltage.

While I was in there, I also found that a 33k resistor between the green points increases the voltage range up to 14.5v for the internal voltage trim pot.

Be sure to use one of the methods in this forum to decouple the DC from the case when running them in series.