battery charger output voltage

96terrano · 26-06-2012, 17:12

need help, here, does a normal 12v car battery charger put out the same volts and amps as a car alternator? eg, could i run a car radio off a battery charger

or would it make magic smoke

(RIP) PLANK · 26-06-2012, 17:42

not usually a very stable supply, of course it all depends on the make and model of the charger, have you got an old car battery you could put in line?

supergnome · 26-06-2012, 18:05

If you look at the output of a charger on a scope it is very rough and not a flat line ( constant voltage) as is a battery. Dont run anything from the charger, It won't like it. You can as Plank says put it in a parallel circuit with a battery and that will remove most of the saw tooth edge of the wave from the charger. They are not the same as power supplies for CB's or ham radios which use silicon diodes with the output smoothed by large capacitors to give a much flatter line similar to a battery. David.

96terrano · 26-06-2012, 18:08

cheers, i've got a few batterys about

96terrano · 26-06-2012, 18:25

what about somthing like this with a 12v motorbike battery in parallel

http://www.ebay.co.uk/itm/12V-TRICKL...item2a1e40ee70

(RIP) PLANK · 26-06-2012, 18:27

no, as it's only half an amp, if you had a good battery and left it charging when you weren't listening then yes. But this would not provide the power your stereo would use

26-06-2012, 17:12	#1
96terrano Senior Member Join Date: Jun 2010 Location: Dumfries and Galloway, Scotland Vehicle: Nissan Terrano 2.7TD LWB Posts: 8,024	battery charger output voltage need help, here, does a normal 12v car battery charger put out the same volts and amps as a car alternator? eg, could i run a car radio off a battery charger or would it make magic smoke

26-06-2012, 18:25	#5
96terrano Senior Member Join Date: Jun 2010 Location: Dumfries and Galloway, Scotland Vehicle: Nissan Terrano 2.7TD LWB Posts: 8,024	? what about somthing like this with a 12v motorbike battery in parallel http://www.ebay.co.uk/itm/12V-TRICKL...item2a1e40ee70

26-06-2012, 17:42	#2
(RIP) PLANK Senior Member Join Date: Mar 2006 Location: Central England, in the Heart of the Black Country Vehicle: T2 2004 TDI SE LWB Posts: 7,740	not usually a very stable supply, of course it all depends on the make and model of the charger, have you got an old car battery you could put in line?

26-06-2012, 18:05	#3
supergnome Senior Member Join Date: Sep 2010 Location: Isle of Axholme Vehicle: T2, 2.7 TDI 2002 lwb Posts: 955	If you look at the output of a charger on a scope it is very rough and not a flat line ( constant voltage) as is a battery. Dont run anything from the charger, It won't like it. You can as Plank says put it in a parallel circuit with a battery and that will remove most of the saw tooth edge of the wave from the charger. They are not the same as power supplies for CB's or ham radios which use silicon diodes with the output smoothed by large capacitors to give a much flatter line similar to a battery. David.

26-06-2012, 18:08	#4
96terrano Senior Member Join Date: Jun 2010 Location: Dumfries and Galloway, Scotland Vehicle: Nissan Terrano 2.7TD LWB Posts: 8,024	cheers, i've got a few batterys about

26-06-2012, 18:27	#6
(RIP) PLANK Senior Member Join Date: Mar 2006 Location: Central England, in the Heart of the Black Country Vehicle: T2 2004 TDI SE LWB Posts: 7,740	no, as it's only half an amp, if you had a good battery and left it charging when you weren't listening then yes. But this would not provide the power your stereo would use