### Author Topic: making resistor substitutions, series/parallel?  (Read 2941 times)

#### roofer1

##### making resistor substitutions, series/parallel?
« on: March 16, 2007, 05:29:50 PM »
i have read via searching archives that you can make resistor values of what you need using other resistors hooked together.  how does that work?  i dont understand the whole series vs parallel thing enough obviously...a little help here?  ahhh...the questions of the young....thanks!

#### calculating_infinity

##### Re: making resistor substitutions, series/parallel?
« Reply #1 on: March 16, 2007, 05:37:15 PM »
Direct from the wiki.
"You can add these in series to get other values. RT = R1 + R2 + R3 etc...
You can put resistors in parallel to get other values.
For 2 values: RT = (R1 X R2 )/ (R1 + R2)
For 2 or more: RT = 1 / ( 1/R1 + 1/R2 + 1/RN ...)"

So if you are using 2, the product of both values divided by the sum of the values is what resistance you should have.

As far as series, from my knowledge just add the values together to get the total resistance.

-Jonathan