Chapter 10 Raceway Systems 145 Copyright Goodheart-Willcox Co., Inc. PROCEDURE Offset Bend after f t e an Obstruction 1. Measure e the height of the offset. t Measure ff ff the distance di between the connection n point o in and the edge of the o ob struction, and m ma rk the conduit at this s distance. d 2. 2 Consult an offset bend n d chart or calculator ff to determine the angle a you would like to use for the offset s et bends. Note the shrink ff amount and d the t distance between the bends at yo y ou r chosen angle. Note: If the t he conduit i t will be installed on a continuo ti nu ou s surfa f ac e (no change in level after e r the h ob- str t ru ction), the angle of the bend b en ds after the obstruction most likely will wi ll be b the same as the angle used before the th e obstruction. 3. Using the distance betw b et we en the bends (from step 2), mark r k the th conduit forward from the fi rst mark m ar k. fi 4. Place the condu o nd ui t bender handle on the he floor and d secure s ec it in place with your u r foot. fl 5. Position on th t he conduit in the bende er so that the e first fi r st mark is aligned with the th arrow. fi fi 6. Bend B e nd the conduit to the angle gl determined in in step 2, being careful no n ot to kink it. 7. 7 Without removing the e conduit from the bender, rotate the conduit c 180° and slide it until the second n d mark is aligned with the he arrow. 8. Bend the co c on duit to the angle determined e rm in step 2, 2, being careful not to kink nk it. PROCEDURE Box Offset A box offset t is i made with two shallow o w bends of t t about 5°, bringing br the conduit off f th t he mounting ° surface e so that it can fit into a knockout kn hole of an electrical e le box. It is the most os common type of off of fs et, since it is used at m mo st electrical boxes. See Figure 10-11. 1. Make one mark k 2″ 2 from the end of the ″ conduit that t will w connect to the box. 2. Make a second ec mark 8″ from the same me en e nd ″ of the co c on duit. 3. Place c e the conduit bender handle l e o on the floor o and secure it with your foot f oo t. Position fl the conduit in the bender r so so that t the 2″ mark is aligned with the he ar a rr ow. Bend the conduit to a 5° angle. e 4. Without removing ng the t he conduit from the bender, rotate the t he conduit 180° and slide e it i t forward (away wa y from fr you) until the secon o nd mark is align l ig g ne d with the arrow. Bend d the conduit ui t (now ( n in the opposite direction) ec to a 5° angle. a ng 5. Test-fit Te st (or install) the conduit ui t with the box. fi The Th end should be aligned e d with the knock- out while the remainder de of the conduit is fl ush against the wall. w al fl PRO TIP Keeping e e Bends Aligned When W putting two bends ds in a piece of conduit, they must be in perfect ec alignment so the con- duit will lie flat agai ga in st the wall. If one bend nd veers to the left and an the other veers to the right, ig the conduit will i ll not lie flat. To maintain align- a ment, find a a seam in a concrete or tile e floor, if available. Li L in e up the first bend and the th bender with the e seam to keep the second nd bend prop- erly aligned. a li PROCEDURE Saddle Bend The saddle bend b goes around an obstruction ob d and, unlike k e the offset bend, returns ns to the same level aft af te r passing the obstruc u ct ion. The most common mm saddle consists of one on 45° center bend and an d two 22 1/2° lateral bend en ds . See Figure 10-12. 1. Measure the height ht of the obstruction (for example, 4″ high). g h ″ 2. Measure the e d di stance between the con- nection poi po in t and the center of the ob- ob struction o n (20″ in this example). ″ 3. For every ev 1″ of obstruction height, g ht move ″ the h e center mark forward 3/16″ 6 ″ (a ( as suming ″ 1/2″ conduit is being used). d ) (In ( I n this exam- ″ ple, 4 × 3/16″ = 3/4″. ″ Mark a rk the t conduit with ″ this new center mark, k at at 20 3/4″.) ″ (Continued)