Conduit Bending

Houses in America are wired in many different ways. Some are wired in NM (Non-metallic sheath), some in BX and still others are installed in conduit. Conduit provides many distinct advantages over NM (Romex) and BX (Metal Sheathed) wiring. Conduit protects the wire from damage, is bonded to ground throughout the circuit, and leaves you with the ability to come back later and add circuits

 bender

The different types of conduit bends, as well as the factors involved in accurately calculating bends are discussed in this section.
The pages for Offset Bends and Segment Bends each contain bending calculators.  The user can enter sample dimensions for the type of bend, and the calculator will give the desired measurements.  I will add other calculators as I develop them.
These calculators are tested on Microsoft Internet Explorer 4.0 and Netscape Navigator 4.05, and may not work with other browsers.

The Right Triangle and the Trigonometric Functions

There are several trigonometric functions that electricians need to know to be able to understand and make the calculations necessary for bending conduit.
Figure 1 is a drawing of a typical right triangle used to give a graphic display of the trigonometric functions used to calculate the angles and lengths used to fabricate conduit bends. 
Ø represents the angle used to bend a piece of conduit, or the angle to be calculated if the lengths of two of the sides are known. 
The Hypotenuse is the side opposite the right angle of the triangle. 
The Opposite side is the side opposite the angle Ø.  
The Adjacent side is the side adjacent to the angle Ø.
Figure 1 shows the 6 trigonometric functions commonly used by electricians.  Trigonometric functions are used to calculate the relationships of the sides and angles of a right triangle. 

1. The Sine, or Sin of the angle Ø is the length of the side Opposite the angle Ø divided by the length of the Hypotenuse.
2. The Cosine, or Cos of the angle Ø is the length of the side Adjacent to the angle Ø divided by the length of the Hypotenuse.
3. The Tangent, of Tan of the angle Ø is the length of the side Opposite the angle Ø divided by the length of the side Adjacent to the angle Ø.
4. The Cotangent, or Cot of the angle Ø is the length of the side of the triangle Adjacent to the angle Ø divided by the length of the side Opposite the angle Ø.
5. The Secant, or Sec of the angle Ø is the length of the Hypotenuse of the triangle divided by the length of the side Adjacent to the angle Ø.
6. The Cosecant, or Csc of the angle Ø is the length of the Hypotenuse of the triangle divided by the length of the side Opposite the angle Ø.

These functions will be used in several formulas to explain the theory of conduit bending.
Follow the links below for information about the different types of conduit bends and how these functions and triangle are used.