high leg delta nec | Solar panel wholesaler

high leg delta nec

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The NEC Code requires that the high leg be identified by an orange color (it was often referred to as a red-leg delta) or by other effective means and is usually the鈥淏鈥?phase. However,to accommodate utility meter configurations the high leg is permitted to be the 鈥淐鈥?phase where metering is part of the switchboard or panel board.

People also ask


  • What is a high leg delta connection?

  • A high leg delta connection is a configuration in which one of the windings in a delta connected secondary of a transformer is centre-tapped and grounded. It is also known as red leg connection or wild leg connection or orange leg connection. By doing so, we are creating a split phase supply as well as a three-phase delta connected supply.

  • What are the NEC rules for the high leg?

  • Other important NEC rules relating to the high leg are as follows: Panelboards 鈥?Since 1975, panelboards supplied by a 4-wire, delta-connected, 3-phase system must have the high-leg conductor terminate to the 鈥淏鈥?phase of a panelboard [408.3 (E)].

  • How do you connect 240V to a high leg delta line?

  • In the same panel having a high leg delta line, we may connect and install single phase 240V loads. To do so, simply connect the appliance (water heater in our case) via two poles breaker connected to two hot wires (such as Hot 1, Hot2 and Hot 3) and ground wire. Connect the additional neutral wire if needed.

  • How many wires does a high leg delta panel need?

  • In a high leg delta panel, we need four or five wires (three as hot) for three phase 240V circuits. As shown in the following fig, we have two appliances viz three phase motor and L21-30R or L21-20R outlet.

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