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2 ohm 1/2 watt 5% Resistor - Replacement Answered

I'm trying to find what 2 resistors I could use in parallel to replace a single 2 ohm 1/2 watt 5% resistor. E24 series. Red/Black/Gold/Gold

Thanks,

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Howard_S (author)2013-12-16

Ok, for everyone that replied to my question, thank you for your time. Everyone was helpful in my decisions. I just went ahead a order from digikey. However, I am a bit worried I may have order the wrong resistor. The burnt out one and the ones I received are vastly different in appearance. They both have the same coding but the physical appearance is totally different. So now my question is, are they same and can use these new ones in place of the old one?

Thanks.

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iceng (author)Howard_S2013-12-16

Different manufacturers of resistors use different back colors.
Also some resistors a carbon composite and others are metal or carbon film.

If the size is the same and the measured resistance by ohmeter is the same
it should work.

I don't remember you telling us what the board does ?

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Howard_S (author)iceng2013-12-16

It's a convergence board for a Projection Screen TV. DP1X CONVERGENCE PWB.

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iceng (author)2013-12-10

Sure, you can do this in your head !

Two identical resistors in parallel will be half the resistance.

So what value divided by two results in 2 Ohms
and since the 1/2 Watt is now distributed across two identical resistors
they are only 1/4 Watt each.

Four ohms 1/4 W in parallel with another four ohms 1/4 W is two ohms at a 1/2 watt..

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Josehf Murchison (author)iceng2013-12-11

Teacher Teacher Me Me Me I know the answer its 4.

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iceng (author)Josehf Murchison2013-12-11

Stop Jumping Josehf, calm yourself, eat a pepper  and back to your chair !  :¬o

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user

Oh my I just looked at your picks.

You want to ether replace the 2 ohm with a 2 ohm or you want to take out the other 2 ohm and install three 3 ohm 1/2 watt resistors.

Orange for 3 Black for 0 Gold for multiply by 0.1 and Gold for 5% tolerance 1/2 watt.

You started with two 2 ohm 1/2 watt resistors in parallel making the circuit 1 ohm 1 watt.

You could also use one 1 ohm 1 watt 1 or 2% tolerance.

Brown for 1 Black for 0 Gold for multiply by 0.1 and Brown for 1% tolerance or Red for 2% 1 watt.

An odd thing happens when you parallel resistors they get more precise, manufactures do it because precise resistors are expensive.

By the way a short cut to calculating resistors in parallel of the same value is to take the value of one of the resistors and divide it by the number of resistors.

Joe

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Josehf Murchison (author)2013-12-11

That is a 2 ohm 1/2 watt 5% tolerance resistor.

Red for 2 Black for 0 Gold for multiply by 0.1 and Gold for 5% tolerance.

To put two in parallel and get the same impedance you double your resistance and half the wattage so you want two 4 ohm 1/4 watt 5% tolerance resistors.

Yellow for 4 Black for 0 Gold for multiply by 0.1 and Gold for 5% tolerance.

2, Yellow, Black, Gold, Gold, 1/4 watt 5% tolerance resistors.

Joe

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Howard_S (author)2013-12-11

Well, I only have places for 2 Resistors. I uploaded 3 images. 2 of the images show 1 side of board. RX50 was the original placement of the 2 ohm Res. RX49 is the extra. Maybe it would be better to ask if anyone here knows where I can order a 2 ohm 1/2 watt resistor. I have looked all over for a place. ebay, amazon, etc. This was my last resort to maybe be able to use 2 or 1. Anyways, any help would be fantastic. well nevermind I cannot seem to upload images from my tablet. Ill try adding them from my PC, when I can.

Thanks

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iceng (author)Howard_S2013-12-11

Turn to DigiKey for a 14¢ 2 ohm 1/2 watt resistor.

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benmurton (author)2013-12-10

resistance in parallel is worked out by, 1/Rtotal=1/R1+1/R2... so using that equation you should easily be able to find a matching two resistors.

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