ac12v 500mA or 3000mA?

hi hi · 09-28-2009, 05:07 AM

hi,
im trying to buy an adapter for my device which reads it needs a AC in 12v - 500mA. the adapter I have is the same except it has 3000mA. does more mA equal more stability? or will it fry my device? i don't think so because its the voltage that would do this right? any knowledge of this kind of thing would be very grateful.
thank you.

**octaneman** · 09-28-2009, 07:52 AM

Hi hihi

Milliamperes on batteries or chargers means that a battery or charger will supply 500mA for 1 hour, it doesn't mean stability, as for voltage think of it as water pressure inside a pipe. If the pressure (voltage) is lower in the adapter, then it will cause the device to drain it faster because there is not enough charge to sustain it. If the amperage rating were higher, then it would cause the device to burn. The basic rule to apply here is Ohms Law where E= I R. For example: Suppose you have a battery that needs charging. A charge is built up in a battery if the current is pumped into it slowly, if it is done too quickly, the battery heats up fast and it burns out.

DonaldG · 09-28-2009, 01:42 PM

Put simply, the 3000ma device will be fine. Go ahead and use it.

It will supply UP TO 3000ma. Your device will take only what it needs. IE: less than 500mA and that is all the device will take from the power supply.

**Done_Fishin** · 09-29-2009, 11:44 AM

I agree with Don .. the device will only ask for what it needs and the supply will also stay cooler since it doesn't need to go to limits!!

09-28-2009, 05:07 AM	#1 (permalink)
hi hi Registered User Join Date: May 2008 Posts: 72 OS: xp	ac12v 500mA or 3000mA? hi, im trying to buy an adapter for my device which reads it needs a AC in 12v - 500mA. the adapter I have is the same except it has 3000mA. does more mA equal more stability? or will it fry my device? i don't think so because its the voltage that would do this right? any knowledge of this kind of thing would be very grateful. thank you.

09-28-2009, 07:52 AM	#2 (permalink)
octaneman Mentor Home Support, Gearhead Automotive Center Join Date: May 2009 Posts: 541 OS: WINXP	Re: ac12v 500mA or 3000mA? Hi hihi Milliamperes on batteries or chargers means that a battery or charger will supply 500mA for 1 hour, it doesn't mean stability, as for voltage think of it as water pressure inside a pipe. If the pressure (voltage) is lower in the adapter, then it will cause the device to drain it faster because there is not enough charge to sustain it. If the amperage rating were higher, then it would cause the device to burn. The basic rule to apply here is Ohms Law where E= I R. For example: Suppose you have a battery that needs charging. A charge is built up in a battery if the current is pumped into it slowly, if it is done too quickly, the battery heats up fast and it burns out. Last edited by octaneman; 09-28-2009 at 08:09 AM.

09-28-2009, 01:42 PM	#3 (permalink)
DonaldG Manager Home Support, Assistant Manager Articles Team Join Date: Aug 2007 Location: Somerset, UK Posts: 10,164 OS: XPsp2 Laptop & Vista Ultimate Desktop My System Blog Entries: 1	Re: ac12v 500mA or 3000mA? Put simply, the 3000ma device will be fine. Go ahead and use it. It will supply UP TO 3000ma. Your device will take only what it needs. IE: less than 500mA and that is all the device will take from the power supply. __________________ . Lest we forget... "They shall grow not old, as we that are left grow old; Age shall not weary them, nor the years condemn. At the going down of the sun and in the morning We will remember them." Submit New Articles Here TSF's Photographer's Corner . Last edited by DonaldG; 09-28-2009 at 01:43 PM.

09-29-2009, 11:44 AM	#4 (permalink)
Done_Fishin Moderator Hardware Team Join Date: Oct 2006 Location: Brit living in Greece Posts: 7,370 OS: WinME, WinXP Pro SP3, Win7 Beta, Ubuntu 9.04 & Netbook Remix & CD2USB, Mepis 6.5, Fedora 10 My System	Re: ac12v 500mA or 3000mA? I agree with Don .. the device will only ask for what it needs and the supply will also stay cooler since it doesn't need to go to limits!! __________________ . . I'm not old!! I'm age impaired .. D_F I DON'T PLAY GAMES How to mark your thread as solved HDD DIAG UTILS TSF's Photographer's Corner