Low charging current?

[shorza]

I have an ex-server HP power supply to run my 400W Turnigy charger. The setup works well apart from the fact that the charge will only charge at a maximum of 9.5amps @ 22volts. By my calculations, that is only a little over 200w.

The power supply states that it is a 575w (max) and the charger is 400w, so why am i only getting around 200w?

 

[shorza]

Am i best ordering a 'better' power supply like a Meanwell?

 

[chroot]

HI, I have same HP server power supply 1125 watts at 25V (dual power supply), It works fine on my iCharger 3010B and Are you running just single HP server power supply which it gives you 12V, 575 watt, and 47A.

It has do with your charger isn't charging at full power. My iCharger 3010B is doing superb job complete charge my 20s2p for 30 mins.

 

[Hillhater]

If you check the spec of your charger, you will see that it needs 15+v to give the max charge rate.
So yes, you most likely need a higher voltage supply to get more charge amps.

Spec.
Input voltage: 11.0 – 18.0Volt
Charge current: 0.1 – 20.0A
Discharge current: 0.1 – 5.0A
Maximum charge capacity: 400W @ input voltage >15V

 

[shorza]

Thanks for the reply guys.
Yes I am only running the one unit @ 12 volts. Is an extra 3 volts going to let the charger pump out 10 extra amps.
I guess I need to up it to 15 volts somehow. Any ideas how?

 

[dogman dan]

Input says 110-240v. Possibly it needs 240 to put out the max spec? Charger menus are complicated too, possible you did something there that is holding back the charger watts?

 

[shorza]

I am giving it 240v, i'm from Australia.

It doesn't matter if i opt for 'Fast Charge' or 'Standard Charge'. I can also set the current, but if i set it to 20A, it still only puts out 9.5A.

 

[shorza]

Would paralleling 2 power supplies of the same type let the charger throw out higher amps?
Is there any danger in doing this?

 

[heathyoung]

Its not the current thats the problem - its the voltage. You need 2 in series (if the charger can cope with 24V input) - putting them in parallel could let free the magic smoke.

 

[neptronix]

If you check the spec of your charger, you will see that it needs 15+v to give the max charge rate.
So yes, you most likely need a higher voltage supply to get more charge amps.

Spec.
Input voltage: 11.0 – 18.0Volt
Charge current: 0.1 – 20.0A
Discharge current: 0.1 – 5.0A
Maximum charge capacity: 400W @ input voltage >15V

See above post for answer

 

[shorza]

Cheers guys.
Looks like i have to start searching for a 15V 350W Mean Well clone.

 

[neptronix]

Actually, here's a better idea.
Keep the balancing charger around, and get a 48v meanwell. The one i just got from sure electronics can adjust from 39v to 59v, so one of those 350w 48v units would be good for 10s-14S.

Add the current limiter pot and you got yourself a nice ~7 amp charger.
Buy two and run them in parallel and ya got ~14 amps.
And so on.

Use the meanwell for non-balanced charges, and the turnigy unit for occasional balancing.

 

[Hillhater]

Would paralleling 2 power supplies of the same type let the charger throw out higher amps?
Is there any danger in doing this?

If you have another PSU , then you can hook them up in series and regulate the voltage down to suit the charger.. like this where he used multiple PSU's to get a high voltage for bulk charging ..
This thread may be helpful ..http://endless-sphere.com/forums/viewtopic.php?f=14&t=26877&start=30

My 3r160 dell PSU's are working great !! I can bulk charge 36 volts with four in series and can balanace each cell using, one 10 amps no problem. Voltage is adjustable with potentimeter 3.6 to 12 volts

The next step is to make them constant current charge, without having to readjust through the charge. I know tons of write ups on mean wells supplies etc.
Any ideas out there, that do not require E.E. degree would be great !

Thanks to all for including me on the Sphere

 

[shorza]

Hillhater, what if i bought another power supply similar to my current one, same voltage but different amperage?
Can i connect them in serial?
Then how would i regulate the voltage down from 24v to 15v?

 

[Hillhater]

If you read the thread i linked to in the last post , it will give you a guide to the use of 2 or more PSUs.
but in summary, yes you can hook 2 different PSUs in series ( different amperage , and/or different voltage ) and you will get a result that is the sum of the voltages, but limited to the amperage of the lowest PSU.
So, if you had a 12v, 47 A and a 6 volt, 15 A ...connected in series , you would get a 18v, 15A output.
To regulate the voltage, look at the diagram above. ( just visualize only 2 PSUs)

PS, There was a guy on Ebay in Sydney selling 500w Dell PSU's @ $19 for a pair !
http://www.ebay.com.au/itm/2xPoweredge-2650-Power-Supply-0H694-J1540-PE2650-/250807683734?pt=AU_Servers&hash=item3a654d8a96