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Electronics: plug 1.2A supply into 1A

 
Rancher
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I bought a new router in Singapore, rather than buy a new power supply I'd like to know if I can use a spare one from home.

The correct power supply is rated at 12V, 1A
The substitute is rated at 12V, 1.2A

My feeling is this should be fine, but I'd like to know before blowing up my new Wireless 'N' router.
 
Wanderer
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It sounds OK. I mean, as long as it's not my router.

Seriously, I would think that 1.2 is the max that it can deliver, but the amount that actually gets drawn depends on the voltage (which is exactly correct) and the impedance of the router. If the router's designed to take 12 V and draw no more than 1 A current, hooking it up to a source that can provide 1.2 A should make no difference at all. I think.

Unless the difference in ratings reflects a difference in internal resistance. The 1.2 A source might have less internal resistance, which translates into less "protection" for your router.

Hm, you should probably wait for info from someone who knows more about what those ratings actually mean.
[ January 24, 2008: Message edited by: Jim Yingst ]
 
David O'Meara
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That was kind of my thought as well. Going the other way would be a bad idea, since having a max supply of (for example) 0.8A when 1A is required could make the router misbehave.

I had a knowledgeable friend that said doing this was OK in some case previously, but I can't remember the exact circumstances.
 
whippersnapper
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Electricity scares me.

I burned up my electric razor (US model) halfway through shaving my face my first morning in Singapore. I wasn't thinking and just plugged it in. It fit and worked (for a few minutes, at least). (I had forgotten about converter/adapters and that electicity particles jump up and down differently at the equator, or whatever.)
 
Ranch Hand
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Hi David,

I have a background in electronics.

The rating on the power supply is how much it can deliver, so it is ok to substitute a 1.2A supply for a burnt out 1.0A supply. *BUT* (very important), you need to be very sure the polarity of the connector of the 1.2 supply is the same as the 1.0 supply, or you will burn out your router! The polarity is normally etched into the casing of the supply.

Aloha,
Doug

-- Nothing is impossible if I'mPossible
 
David O'Meara
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Perfect Doug. Thanks!
Nice pointer on the polarity, I hadn't considered that.
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