RunRyder RC
WATCH
 3 pages [ <<    <    ( 1 )     2      3     NEXT    >> ] 1429 views POST REPLY
HomeAircraftHelicopterMain Discussion › charger input voltage vs max output?
03-16-2015 11:52 AM  3 years agoPost 1
emederos

rrApprentice

Miami, Fl Dade

My Posts: All  Forum  Topic

Hi all my charger is rated at 400w at 18v, how can i know what I'm able to put out at 12v? Reason i ask is i have 3 6s 5000mah packs and want to parallel charge but just thought about it and i will not be able to charge the 3 packs on the board as i intended if I'm not pushing 18v input. My charger is 20a 400w based on my calculations i was planning on charging 3 packs at 1c sac (15a) and that will be pushing 378w but now i think about it i won't be able to do that at 12v....Not only that i checked Hitec manual and it specifies a 6s pack maximum output current is only 16a??? bummer. 1,2 and 3s packs are the only that you can charge at 20a given the 18v input voltage. Any help will be appreciated eace

PM  EMAIL  GALLERY  Attn:RR  Quote
03-16-2015 12:59 PM  3 years agoPost 2
fenderstrat

rrProfessor

Aston,Pa

My Posts: All  Forum  Topic

I am not trying to sound like a know it all or smart ass,but from your questions it sounds like you are not familiar with even the most basic formulas for charging.Charging lipos in parallel or series is not something to be taken lightly,3 6s 5000mah batteries packs a lot of punch and can burn down a house.before you do any charging I suggest you do as much research as possible to get as much knowledge as possible.

I will give you some of the basics here but as said you really need to do some learning to have all the info.It is more than can be covered in a singe post

The basic equation you need is W=VxA which is Watts equals Volts times Amps.The limiting factors here are the output watts of your charger and the number of cells/mah in the batteries you are charging.For example take your 400 watt charger.

If you are charging 6s batteries, fully charged, they are at about 25V(22.2 nominal),and we will use this for simple math.So 400watts(output of your charger)divided by 25V means you can charge this battery at 16 Amps.So you can charge 1 6s 5000mah battery at 3c(15A)or 3 6s 5000mah batteries at 1C.

Now if you are using 3s batteries the voltage is halved so you have 2 times the Amps to work with.For example a 3s 5000mah(12.6 fresh off charger) battery would be able to be charged theoretically at 33 Amps,assuming a 400 watt charger since 400/12 is roughly 33.
These numbers are extremely simplified and only to round numbers but you get the idea.So try to absorb some of this do some research and then ask any more questions

oh and to answer this
Hi all my charger is rated at 400w at 18v, how can i know what I'm able to put out at 12v
only the manufacturer of that charger can tell you what the max output is at 12V

Compass helis Support Team
PerformancePlusRC field rep
Mini Titan/SE
TEAM KBDD

PM  EMAIL  GALLERY  Attn:RR  Quote
03-16-2015 01:11 PM  3 years agoPost 3
fenderstrat

rrProfessor

Aston,Pa

My Posts: All  Forum  Topic

this site is must read for anyone serious about elec helis and charging.everything you need to know in one spot

http://www.tjinguytech.com/home

Compass helis Support Team
PerformancePlusRC field rep
Mini Titan/SE
TEAM KBDD

PM  EMAIL  GALLERY  Attn:RR  Quote
03-16-2015 01:20 PM  3 years agoPost 4
emederos

rrApprentice

Miami, Fl Dade

My Posts: All  Forum  Topic

My question is basically will i be able to parallel 3 packs on 400w 20a?

PM  EMAIL  GALLERY  Attn:RR  Quote
03-16-2015 01:23 PM  3 years agoPost 5
emederos

rrApprentice

Miami, Fl Dade

My Posts: All  Forum  Topic

I know how to charge single packs just trying to get the most out of my charger and PSU

PM  EMAIL  GALLERY  Attn:RR  Quote
03-16-2015 01:34 PM  3 years agoPost 6
fenderstrat

rrProfessor

Aston,Pa

My Posts: All  Forum  Topic

it all depends on the number of cells and mah of the packs.and what the charger puts out at 12V

Compass helis Support Team
PerformancePlusRC field rep
Mini Titan/SE
TEAM KBDD

PM  EMAIL  GALLERY  Attn:RR  Quote
03-16-2015 02:09 PM  3 years agoPost 7
emederos

rrApprentice

Miami, Fl Dade

My Posts: All  Forum  Topic

Actually im just trying to get 4 packs charged at half the time. A 6s pack at 1C is about 126 watts , 2 packs on paraboard at 1c 5000mah will be roughly 250 watts. Having 4 packs im looking to purchase 2 paraboards to cut charging time in half....

CHARGER IS HITEC X2400 dual port

At 18v it puts out 400w but im running it at 12v input assuming im still getting at least 250w output power

PM  EMAIL  GALLERY  Attn:RR  Quote
03-16-2015 04:37 PM  3 years agoPost 8
Pistol Pete

rrProfessor

Seffner, FL

My Posts: All  Forum  Topic

HITEC X2400 dual port
SPECS: 16A MAX for a 6S batt (per port)

When you parallel charge, the 16A is divided by the number of batteries you connect to the board.

So charging TWO 6S-5000mAh in parallel means they each get 8A which is about 1.5C.

The charger needs to output twice the face value of the "mAh" battery in order to cut your charge time in half.

The only way to know for sure if your charger can output 16A with 12V as input is to connect a 6S to it and MAX it out PROVIDED your batt can handle 3C charging. That is until you get the parallel board/cables.

~~Enjoying the hobby one flight at a time~~

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
03-16-2015 04:42 PM  3 years agoPost 9
emederos

rrApprentice

Miami, Fl Dade

My Posts: All  Forum  Topic

Im only planning on charging 1C per port 252w at 10 amps, i have the Geforce lipo packs and have done research nothing found on if they can handle even 2c chg rating so i keep em at 1C

PM  EMAIL  GALLERY  Attn:RR  Quote
03-16-2015 04:47 PM  3 years agoPost 10
Pistol Pete

rrProfessor

Seffner, FL

My Posts: All  Forum  Topic

Given the 1C charging intended, you can charge up to THREE 6S-5000mAh in parallel per port.

I would contact valuehobby for that "2C" piece of information as they seem to be the disrtibutor.

~~Enjoying the hobby one flight at a time~~

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
03-17-2015 12:10 AM  3 years agoPost 11
emederos

rrApprentice

Miami, Fl Dade

My Posts: All  Forum  Topic

Well if im just parallel 2 packs at 1c im just charging 2 packs at 1c its 10 amps, now thats still at 1c correct? Or is that considering both packs are getting a 2c charge rate?

PM  EMAIL  GALLERY  Attn:RR  Quote
03-17-2015 01:35 AM  3 years agoPost 12
Pistol Pete

rrProfessor

Seffner, FL

My Posts: All  Forum  Topic

Yes, TWO 5000mAh packs in parallel at 10A is 1C.

Keep in mind you only have 4000mAh available based on the 80% rule. If you are charging more than that, shorten your flight time accordingly.

~~Enjoying the hobby one flight at a time~~

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
03-17-2015 01:57 AM  3 years agoPost 13
emederos

rrApprentice

Miami, Fl Dade

My Posts: All  Forum  Topic

I plan on putting the batteries at storage voltage after flight and I always fly 30 to 35 percent, from storage voltage whatever I'm going to go fly I'll just go ahead and parallel charge them so that pretty much the same level

PM  EMAIL  GALLERY  Attn:RR  Quote
03-17-2015 02:42 AM  3 years agoPost 14
McKrackin

rrProfessor

Lucasville,Ohio

My Posts: All  Forum  Topic

I doubt you'll even get 10 amps with 12V 400W.

My power supply is 1080W and 18V and can only do 26 amps.
If you manage to get 10 amps with what you have,it will be running hard and hot.

I literally never use the word literally right.

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
03-17-2015 02:55 AM  3 years agoPost 15
emederos

rrApprentice

Miami, Fl Dade

My Posts: All  Forum  Topic

All comes down to charge rate what are you charging and at what rate?

PM  EMAIL  GALLERY  Attn:RR  Quote
03-17-2015 02:57 AM  3 years agoPost 16
McKrackin

rrProfessor

Lucasville,Ohio

My Posts: All  Forum  Topic

5000mA 6S packs and it makes no difference.
A 1000W 18V power supply will do 26 amps max no matter what you have hooked to it.

That might be 5C on one pack and 2.5C on two but no matter what you do,it will not do more than 26 amps.Period.

You need higher input voltage to get more out of it.

I literally never use the word literally right.

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
03-17-2015 03:05 AM  3 years agoPost 17
emederos

rrApprentice

Miami, Fl Dade

My Posts: All  Forum  Topic

At 1c all I need is 126w per pack , 2 packs are 252w can you explain why at 12v input and 400w power why is this not suitable?

PM  EMAIL  GALLERY  Attn:RR  Quote
03-17-2015 03:23 AM  3 years agoPost 18
McKrackin

rrProfessor

Lucasville,Ohio

My Posts: All  Forum  Topic

I can't explain it.
I just know what happens.

My 12V 350W power supply will only do 7.5 amps.

I literally never use the word literally right.

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
03-17-2015 03:49 AM  3 years agoPost 19
McKrackin

rrProfessor

Lucasville,Ohio

My Posts: All  Forum  Topic

Now I don't know what results you'll get and I don't understand the math behind this stuff.

Just passing along my experience.
Results may vary

I literally never use the word literally right.

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
03-17-2015 04:02 AM  3 years agoPost 20
EEngineer

rrProfessor

TX

My Posts: All  Forum  Topic

12V 350W power supply will only do 7.5 amps.
Not exactly sure what you mean...

I'm guessing with that PS....and the charger that your PS is supplying power to......results at a charge rate of 7.5A max...regardless of "C" setting on the charger?

PM  EMAIL  Attn:RR  Quote
WATCH
 3 pages [ <<    <    ( 1 )     2      3     NEXT    >> ] 1429 views POST REPLY
HomeAircraftHelicopterMain Discussion › charger input voltage vs max output?
 Print TOPIC  Make Suggestion 

 6  Topic Subscribe

Tuesday, July 17 - 10:38 pm - Copyright © 2000-2018 RunRyder   EMAILEnable Cookies

Login Here
 New Subscriptions 
 Buddies Online