[habsbob]

I just added a new electrical outlet from an existing one.

The original has black and red on the hot side and a white on the other.

My new wire has black and white only.

How do I do it?

I had left the red in place, had put both black together and both white on the other side and it shorted

 

[joed]

Sounds like a split wired receptacle that has two 15 amp circuits connected to it. If you only connected the new receptacle to the black and white it should have been fine if you left the old one in place. The old one would have had the tab cut between the screws on the hot side.

 

[J. V.]

Red might be a switch leg. See if a switch kills power to the red or the black. Choose the one the switch does not operate.
The tab is broken on the hot side of the recept right?