#### Shield Coverage:

The following equation can be used to determine the percent coverage of a braided or spiral shield:

**Braid Shield**\[Tan(a) = \frac{{2\pi (D + 2d)P}}{C}\]

**Spiral Shield**\[Tan(a) = \frac{{\pi P(D + d)}}{C}\]

**Variables**

**D** is diameter under shield (inches)

**d** is diameter of strand, inches (Typically #30 AWG Solid to #40 AWG Solid)

**P** is picks per inch

**N** is number of strands per carrier (typically integer values of 1 to 13)

**a** is shield angle, degrees

**%** is percent coverage (must be less than 100%)

**Where:**

for Braid Shields

for Spiral Shields

**And:**

#### Shield Resistance:

The D.C. resistance for braided shields can be calculated using the following equation:

**Variables**

**R** is D.C. resistance, (ohms/m^{1}) for the braided shield construction

**r** is D.C. resistance of 1 strand (ohms/m^{1})

**a** is braid angle, degrees

**N** is number of strands per carrier

**C** is number of carriers