Resistor help

dyno

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I need to replace a wire wound ceramic resistor on a chassis, it says on it 9watts 4R7. Can anyone tell me what the 4R7 means, I asssume it is the ohms and where would be a good place to buy a replacement. Also can I put in a 10 watt resistor or does it have to be the same wattage or lower.
 
Any idea where I can find a 4.7 ohm 10 watt radial ceramic wire wound resistor, I am not having much luck finding one. The only one I can seem to find is a 4.7 ohm 5 watt which I don't think will work.
 
while not elegant, you can wire 4 of the 5 watt resistors up. Parrallel 2 sets, and run the 2 sets up in series. That gives you both 4.7 ohms and 10w power rating.
Forgive my poor drawing, but this should explain what i mean - all 4 resistors are 4.7 ohm 5 watt - which ends up with a 4.7 ohm 10w rating.

edit - or you could just order one from mouser -
http://www.mouser.com/Search/Refine.aspx?Keyword=280-CR10-4.7-RC
 

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Thanks for the link to mouser but I those are axial mount resistors and I need a radial mount, what would happen if i used a 5 watt resistor instead of a 10 watt resistor? Is that okay to do? I have found a bunch of 4.7 ohm 5 watt radial wire wound ceramic cement resistors for sale.
 
you can swap axial for radial so long as there is physically room.
The watt rating is the amount of power the resistor dissipates - to simplify, how much current it can handle across a particular voltage. A 10w resistor will handle twice the current that a 5w one will, and if you put a 5w resistor in place of a 10 watt one, it'll get real hot, and most likely burn up in short order.

Here's a link on Bob's site showing how to replace a radial cap with an axial one - http://www.therealbobroberts.net/axial.html . Same idea with axial/radial resistors.
 
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