GoldenMotor.com Forum

General Category => Electric/Hybrid Car Conversion => Topic started by: SherylinRM on July 02, 2020, 03:46:17 PM

Title: How much does a charger pull from the wall?
Post by: SherylinRM on July 02, 2020, 03:46:17 PM
I want to get a 45 amp 24 volt charger for lifepo batteries.
However I am concerned about how much power it takes from the wall.
I am limited in the amount of electricity I have at my place.
So 45 times 24 = 1080 watts.
Now at about 40% waste that is 1400 watts correct?
That would be too high as I only have 1440 coming out of the wall. :-\

I could maybe afford 1200 watts if I don't use much of anything. :'(
So maybe get a 30 amp 24 volt charger?
It will take a long time to charge my batteries but I have no real choice. :(

Ok, ideas? thoughts? comments?

Thanks guys  :)
Title: Re: How much does a charger pull from the wall?
Post by: Bikemad on July 02, 2020, 09:20:02 PM
Hi Sherylin,

This 24V 45A charger (https://danlcharger.en.made-in-china.com/product/kvSxViFYEPps/China-24V-45A-Smart-Battery-Charger-for-Lithium-Battery-1500W-High-Power-Charger.html) is rated at 1500 Watts  (29.2 Volts  x  45 Amps = 1314 Watts of output power, which would require ~ 1470 Watts of Input Power @ 90% efficiency).

This 24V 35A charger (https://danlcharger.en.made-in-china.com/product/FvhmJyEDvQGz/China-24V-35A-Waterproof-Marine-Battery-Charger-for-LiFePO4-Battery.html) is rated at 1200 Watts  (29.2 Volts  x  35 Amps = 1022 Watts of output power, which would require 1075 Watts of Input Power @ 95% efficiency).

A 35A charger should be able to fully recharge a completely exhausted 320Ah LiFePO4 pack in ~10 hours, but if you are only using 80% of your battery's capacity it should only need ~8 hours to fully charge it again overnight.

This 24V 30A charger (https://danlcharger.en.made-in-china.com/product/pvsENUxPsVrG/China-24V-29-2V-29-4V-30A-Lithium-Battery-Charger.html) is rated at just 900 Watts  (29.2 Volts  x  30 Amps = 876 Watts of output power, they don't state its actual efficiency, but if it's more than 90% efficient it would require less than 975 Watts of input power).

A 30A charger should still be able to replace 80% of your battery's capacity in ~9 hours, which is probably acceptable.

Why do you only have 1440 Watts power coming out of the wall, are you off grid using a battery powered inverter?

Alan
 


Title: Re: How much does a charger pull from the wall?
Post by: SherylinRM on July 03, 2020, 08:51:27 AM
Once again, Alan the Mad Biker to the rescue.  :D
Thanks :)
But why are you mad?  ::) :P
Title: Re: How much does a charger pull from the wall?
Post by: SherylinRM on July 03, 2020, 08:54:11 AM
Quote from: Bikemad on July 02, 2020, 09:20:02 PM
Hi Sherylin,
Why do you only have 1440 Watts power coming out of the wall, are you off grid using a battery powered inverter?

Alan
I live in Vancouver BC Canada and in city housing. They do not have the greatest of places to live to be honest.
It is a roof over my head though.
The breakers are only 12 amps and the wiring I found out is only 14 gauge. Which scares the frik out of me when you consider how long the runs are.
But that is the way the Mayors do things here soooo.
Can't complain. I at least am not out on the streets.
Title: Re: How much does a charger pull from the wall?
Post by: Bikemad on July 03, 2020, 08:45:10 PM
Quote from: SherylinRM on July 03, 2020, 08:51:27 AM
Once again, Alan the Mad Biker to the rescue.  :D
Thanks :)
But why are you mad?  ::) :P

I'm not a "Mad Biker", I'm just mad about bikes.

Which is slightly different.  ;)

Alan
 
Title: Re: How much does a charger pull from the wall?
Post by: SherylinRM on July 04, 2020, 04:37:11 AM
Quote from: Bikemad on July 03, 2020, 08:45:10 PM
Quote from: SherylinRM on July 03, 2020, 08:51:27 AM
Once again, Alan the Mad Biker to the rescue.  :D
Thanks :)
But why are you mad?  ::) :P

I'm not a "Mad Biker", I'm just mad about bikes.

Which is slightly different.  ;)

Alan

Oh of COURSE there is. I apologize LOL. And I believe you too. LOL :o ;) :)

EDIT: I meant mad as in nutty, not angry  ::)