# Symbol I can't identify ---> ||

Discussion in 'General Electronics Chat' started by Zebidiah, Jul 2, 2014.

1. ### Zebidiah Thread Starter New Member

Jul 2, 2014
1
1
I didn't see any other posts on this so maybe I missed where it was originally explained I the text, but it took me a long time to figure out what the || operator means.

I saw it used here: http://www.allaboutcircuits.com/vol_3/chpt_1/7.html
It was part of an equation Zin= R1 + (R2 || (Z + R1))

The example shows that 35.14||75.97=24.03, but I couldn't figure out what operation generates that result from those two inputs

A||B = (A^(-1) + B^(-1))^(-1)
A footnote on the page or a reminder about Thevenin analysis might help future readers.

Papabravo likes this.
2. ### t_n_k AAC Fanatic!

Mar 6, 2009
5,448
784
Parallel combination of two impedances or resistances.

3. ### Ramussons Active Member

May 3, 2013
623
104
The symbol || means "in Parallel"

35.14||75.97 => (35.14*75.97)/(35.14+75.97) = 24.02651

Ramesh

4. ### Papabravo Expert

Feb 24, 2006
11,123
2,171
Like many other symbols in Engineering it is overloaded. All by itself it may have multiple meanings and the resolution of the ambiguity depends on context. In this context it was used to indicate a parallel combination of impedance.

It is also used in numerous programming languages as the logical OR operation. It may have other uses as well. Don't be surprised when this happens and keep asking authors to explain their notation.