Zap Zach Presents: 120V Panel to Single Switch to 12V Transformer. The service line is connected to a disconnect box with two 30amp fuses and a bull switch. From there it is wired to a 120v, Single Phase panel. Circuit #1 is a 15amp breaker ran with 14/2 M.C. to a 4D junction box with a single pole switch. Per NEC Article 330.30 all MC needs to be secured within 12” of a J-Box (Junction Box). From the single pole switch the 14/2 M.C. is ran to the 10:1 Step-Down Transformer. 120volts to 12 volts is a 10:1 ratio (120 / 12 = 10). The voltage is being stepped down thus a step down transformer. Same principle applies to Step-Up transformers. On the Square D transformer we splice cable H1 with our Hot (Black) service line cable. H4 is then spliced with our Neutral (White) service line. Transformer lines H3 & H2 are then spliced together. This wiring then powers the transformer. To wire a Load to this you would splice X4 with your first positive (+) lead, X1 would be connected to your negative/common/neutral (-) lead and lines X2 & X3 would be sliced together. Apologies for not installing a load onto it.
NEC Article 450 covers Transformers and Transformer Vaults.
*Always wrap you switches with E-tape (Electrical Tape) when installing into metal junction boxes.
*Metal Clad Cable NEC Article 330;
-Article 330.30 (B) SECURING: states cables containing four or fewer conductors sized no larger than 10 AWG shall be secured within 12” of every box, cabinet, fitting, or other cable termination.
-Article 330.30 (C) STRAPPING: Unless otherwise provided, cables shall be supported at intervals not exceeding 6 feet. Horizontal runs of MC cable installed in wooden or metal framing members or similar supporting means shall be considered supported & secured where such support does not exceed 6’ intervals.
-Article 330.30 (C): SUPPORTING: Unless otherwise supported, cables shall be supported at intervals not exceeding 6 feet.
15 сен 2024
