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gerrydoire
September 14th, 2009, 12:17 PM
I have a Router, it requires 9volts, 1000ma.

The best I could find was a 9 volts, 1500ma, will the difference damage the Router, or does the adapter just have a high load capacity than I will need and not damage the Router?

Thanks for any advice!

:)

southbird
September 14th, 2009, 12:20 PM
The rule is to match the voltage as best you can, and have a greater or equal amperage. The amps on the PSU is more of a "max rating", but the device itself will not draw (or be forced to draw) more than it needs. So what you have should be fine, so long as the polarity on the connector matches...

Chuck(G)
September 14th, 2009, 12:38 PM
AC or DC? It matters. Ive got a router here that takes an AC wall wart and one that needs a DC wart.

kishy
September 14th, 2009, 12:57 PM
AC or DC? It matters. Ive got a router here that takes an AC wall wart and one that needs a DC wart.

Wall wart, that's clever lol. Is that your term or have I been missing something?

Agreed on the content of both replies.

A note though: some devices will tolerate a slight under or overvoltage; I've been using 9V on my 12V speakers for ages but they do crackle now as a result. Current won't be a concern as long as it's not too low. Polarity is critical, as is AC vs DC (though a polarity issue usually doesn't damage anything, it simply won't work, but better to be sure before trying).

Chuck(G)
September 14th, 2009, 01:32 PM
Wall wart, that's clever lol. Is that your term or have I been missing something?

The term's at least a couple of decades old. I don't recall when or where I first heard it, but it's a perfect description.

channelmaniac
September 14th, 2009, 05:21 PM
For most routers they are only using +5 or +3.3v to run things. That means if you have a router that takes an AC supply then you can use a DC one as long as the polarity is correct so it can get across the rectifiers.

RJ

gerrydoire
September 14th, 2009, 05:31 PM
The rule is to match the voltage as best you can, and have a greater or equal amperage. The amps on the PSU is more of a "max rating", but the device itself will not draw (or be forced to draw) more than it needs. So what you have should be fine, so long as the polarity on the connector matches...

What I figured, just needed to have someone else say it!

:)

Chuck(G)
September 14th, 2009, 05:42 PM
For most routers they are only using +5 or +3.3v to run things. That means if you have a router that takes an AC supply then you can use a DC one as long as the polarity is correct so it can get across the rectifiers.

If it's a bridge rectifier on the input (as it usually is), does polarity matter?

OTOH, on the outside chance that the rectifier is being used to within an inch of its ratings, a DC supply will pass the full draw current through only half of it, which isn't good practice. But that possibility's pretty remote.