How To Wire a 240 Volt GFCI


For specific schematics of your Omega Diamond 240 volt system, be sure to consult the wiring diagram on the inside of the wiring box on the motor.

Below are some instructions and precautions you will need to provide to a qualified electrician when wiring an Omega Diamond 240 volt system. Before we begin we want to make it perfectly clear that for safety's sake only a qualified electrician can wire an Omega Diamond 240 volt system.

Step 1: Wiring Check Precautions

  • When working in a system box always be aware that it may contain high voltage.
  • Always keep your fingers and hand tools away from any wiring or circuit board when the power is on. Touching anything in these areas can result in serious injury.
  • All service calls, no matter how minor, should include a complete wiring check, beginning with the building breaker.
  • Keep in mind, some Omega Diamond 220 volt systems only run on single phase electrical service. Three phase power will not supply proper voltage to these systems. Three phase power may overheat the motor and cause the GFCI to trip. Do not use three phase power unless clearly specified on the motor!

Step 2: Check for Loose Connections or Damaged Wires

Check for Loose Connections or Damaged Wires
  • Make sure the power is off before you touch any wiring.
  • Once the power is off, carefully examine all wires for cuts or defects.

Step 3: System Box Wire Gauge Check

When inspecting the wiring for any control system, note that connections for the incoming wires are clearly labeled at the main terminal block.

  • 50A service - minimum six gauge copper wire.

These wires must connect the building breaker box, through the local disconnect (GFCI), to the main terminal block inside the motor. The wiring diagram inside the motor box shows the main terminal block as TB1. Pull 4 copper current carrying conductors (one each: black, red, white, green insulated). Use either No. 6 AWG 60 degree C, No. 8 AWG 75 degree C, or No. 8 AWG 90 degree C wire, if the Omega system is 100 feet or less away from its power supply. The GROUND must be equal to or larger than the largest power conductor.

Step 4: Use Only Copper Wire

Using non-copper wire can be dangerous, and also can be the cause of an Omega Diamond 220 volt system malfunction.

Step 5: GFCI Wiring Check

The proper installation of a GFCI is imperative to avoid nuisance tripping once you activate your Omega Diamond 220 volt system. Be sure that the electrician refers to the image above and installs the GFCI accordingly.


The National Electrical Code states that a service disconnect breaker box (a GFCI can be used for this purpose) must be located at least five feet away from a 240v system and should be conveniently located near the equipment bay. If it is not in plain sight, keep the disconnect padlocked when in the off position to avoid serious injury.

REMEMBER: Only a qualified electrician can wire an Omega Diamond 240 volt system!