Navitron Renewable Energy and Sustainability Forum

Energy/Electricity Storage and Use/Grid Connection => Off-Grid, Batteries & Inverters => Topic started by: camillitech on February 21, 2008, 09:42:46 PM



Title: 48v battery charger, how many amps?
Post by: camillitech on February 21, 2008, 09:42:46 PM
Hi guys,

being somewhat electrically inept I was wondering if I'd got this right. Am I right in thinking this http://cgi.ebay.co.uk/Lead-Acid-Battery-Charger-48V-20A-110V-220V-Auto-Switch_W0QQitemZ110224124000QQihZ001QQcategoryZ48618QQrdZ1QQssPageNameZWD2VQQcmdZViewItem?_trksid=p1638.m122 20amp 48v dc , 220 ac charger would draw 5 or 6 amps ???

Cheers chaps ;D


Title: Re: 48v battery charger, how many amps?
Post by: frank2 on February 21, 2008, 10:10:09 PM
hi paul

yes, i make it 960w dc, about 4 1/2a ac +losses = 6 or 7a ?

frank


Title: Re: 48v battery charger, how many amps?
Post by: camillitech on February 21, 2008, 10:37:28 PM
Cheers Frank,

after 1/2 a bottle of red wine and the early onset of alzhiemers I wasn't so sure ;D I'm thinking of getting one so I can put a bit of charge in my battery bank when I'm running up the spare Listers and I know that Bob spoke very highly of 'Ki Point' kit.

Thanks, Paul


Title: Re: 48v battery charger, how many amps?
Post by: Ivan on February 21, 2008, 11:02:31 PM
It's not going to be 100% efficient. Is it switch-mode? I couldn't see it in a quick glance over the specs. If it is switch mode it will be very efficient 90%+. If it is not, it will be less efficient. I think the worst (commonest?) are as low as 50%. If it's 50% efficient, it will draw more from the mains than you'd calculate.


Ivan


Title: Re: 48v battery charger, how many amps?
Post by: SteveH on February 25, 2008, 11:22:06 AM
 
 I have an interest in 48Volt systems too so asked them the question through Ebay... the reply follows:

Quote
Dear Steve,

The input current for 115Vac is max. 25A and for 230v is 13A.

The input voltage for this charger is 110v / 220v auto switch. This charger will sensor the input voltage automatically.

Have you got any questions, please don't hesitate to contact us.

Best regards,

Ivy Chiu

KIPOINT Service Dep.
www.kipoint.com.tw
TEL:886-2-29962085
MSN:service@kipoint.com.tw
Skype: kipoint.skype
E-mail: service@kipoint.com.tw

 I also asked if it was switch mode or transformer based, but that point doesn't seem to have been addressed

 Seems quite a high input current though... Hope this helps.

 Steve.


Title: Re: 48v battery charger, how many amps?
Post by: northern installer on February 25, 2008, 02:32:22 PM
if the charger is tranformer based,watch out for the inrush current too,typically 2-4 times full load current,depending to some extent on the type of transformer.