Academy Crop

3 Phase Operation

3 Phase Diagram

Department Document

Download the document here, or read it below as a webpage.


Our Main Studio (A302) is equipped with a 3 Phase power system. 

This means that a much higher power draw can be serviced than when using regular mains plugs. For your protection the 3 phase system is based on a series of locks, breakers, distro boxes and two types of heavy duty weather proof connectors with heavy gauge wire. The Seeway comes in a five wire connection, and is the main feed into the 3 phase system. The five connections consist of a ground (green), neutral (white), and three hots (blue, red, black). 4AWG (gauge) cable, known as Fivewire, can carry a max load of 100A per hot safely. It is known as five wire because all five strands are loosely bundled together in one wire grouping. Five wire is available for sign out and use in the studio. 2AWG cable, or 3 + 2 cable, can carry a max load of 200A per hot safely. 3+2 cable comes in two separate bundles 3 wires, and 2 wires, because of its heavy weight. It is available from Whites and can provide power for more than all the lights we have a once. Calculating loads will be covered in  the electrical basics page.


Once a 6x50 distro box with attached Diefs has been properly set up, any student may use the Diefs as they would house mains. Plugging and unplugging lights to/from the Diefs does not require 3 phase clearance. People without clearance may not operate the breakers of the distro boxes, however, and may not plug Diefs into distro boxes.

Studio policy for 3 phase usage is strict, and to use or modify connections on the 3 phase system students must be cleared.  Students who have not been cleared caught using or tampering with the 3 phase system will be banned from entering the studio for the remaining duration of their student career at NSCADPlugging equipment into Diefs already properly set up is safe and is exempt from this rule.


  1. Ensure main breaker power is off (in down position). Leave box off and locked until all cables are connected.Take distro box(es) (6 x 50A) and place in ideal location in studio.
  2. Ensure distro has all breakers off.
  3. On main cam box attach 5 wire (this is actually in order from right to left):
  • Connect ground (green)
  • Connect neutral (white)
  • Connect hots
  1. 4. At other end of 5 wire connect cams to Distro box in same order as main cam box - Green, White, Hot x 3. If using both 6x50s be sure to T off five wire.
  2. 5. Bundle excess five wire out of the way, make sure the run to the Distro box is flat and straight. When crossing areas of foot traffic with five wire be sure to cover with a rug, tape down, or otherwise secure the cabling to avoid tripping hazards.
  3. 6. Attach joy to 6x50s as needed.
  4. 7. Attach and position Dief Box(es)
  5. 8. Throw on main power
  6. 9. Turn on distro breakers for banks in use.
  7. 10. Proceed to use Diefs as you would use house mains


  1. Turn on house lights. Turn off all film lights. If you cannot safely reach the switch, turn off the downstream breaker and allow light to cool before lowering it on its stand. Fibreglass ladders are also available to rig/strike lights.
  2. Turn off and lock main breaker.
  3. Disconnect 5 wire cam locks from main breaker.
  4. Turn off all breakers on distro (6 x 50A) boxes.
  5. Disconnect all Diefs and joy cable
  6. Coil all cable properly
  7. Neatly pack all electrical distribution equipment on the brown cart for storage.


Any time joy cable needs to be removed or added to distro, turn off the breakers, make adjustments, ensure Diefs are attached, and turn the breakers back on for only the bank(s) in use. Never turn on breakers for unused banks. Ensure unused banks have breakers in off position. Main switch does NOT need to be off to disconnect, or connect joy - only the breakers of the distro box.

Lights should be balanced across the 3 phases as evenly as possible. Distro boxes have each of the 2 sets of 6 joy connectors colour coded for each of the phases (2 x 50 Amps per phase). This is especially important if both distro boxes are in use. Always keep in mind that our five wire is rated for 100A per phase. This means if both 6x50 boxes are in use and fully loaded on one phase (colour coded) the Fivewire could be overloaded.


Any time 5 wire needs to be adjusted, main switch must be off

If electric crew leaves the studio, main switch must be turned off and locked.

Shoots caught leaving the main box ON or unlocked with no responsible party on set will be immediately shut down and all studio keys revoked!