Power Cord with a 20 amp female and 15 amp male ?

Sadly almost all aftermarket power cord manufacturers make power cords with a 20 amp IEC female connector with a NEMA 125V 5-15P 15 amp plug on the other end. And what's worst the power cord might even be UL listed.

The company that makes the power conditioner makes such a power cord.
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Silver Circle 5.0SE power conditioner

Not sure what good a 5Kva isolation transformer connected to a 120V 20 amp branch circuit let alone a 120V 15 amp branch circuit.

A 5Kva, 5000Va, transformer is good for 41.67 amps continuous FLA at 120Vac.

Available Power in = available power out - core loses.

In other words continuous available power for a 20 amp dedicated 120V branch circuit is 120V X 20 amps = 2400Va.

For a 120V 15 amp dedicated branch the continuous available power is 120V X 15 amps = 1800Va.

If the unit will be plugged into a 120V 15 amp convenience outlet branch circuit that is sharing other loads there is the possibility when the unit is first powered on it may trip the 15 amp branch circuit breaker at the electrical panel due to inrush current.
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My shop inquired with them about it and we were told that the cord was good for 20A usage. As long as the connector is rated for 20A, which in my case the 330i presumably is, the orientation of the tangs is not important.
10-14-15: Reynolds853

Example of the Wattgate 330i plug.

You were told wrong. The 330i is a 5-15P 15 amp rated plug....
NEMA safety standards for plug and receptacles are supposed to prevent the general public from being able to use the wrong voltage, or amperage, plug or receptacle to feed an appliance or a piece of equipment.

Per NEMA, UL, CSA, NEC, ect, the maximum allowed continuous connected FLA load of an appliance or a piece of equipment with a NEMA 5-15P 15 amp rated plug is 12 amps....
For a NEMA 5-20P 20 amp rated plug, 16 amps.

What the PK10 power cord with a 15 amp plug in the eyes of a recognized third party testing laboratory is a 15 amp rated power cord. The wire could be as big as a house but because of the plug configuration it is rated to be used on equipment with an FLA of 12 amps or less. And that is the problem with IEC connectors..... They are not what is called in the electrical industry as being idiot proof.

Good example are consumer portable space heaters and portable vacuum cleaners. Because most of the receptacles in our homes are 15 amp, connected to 15 amp branch circuits, if manufactures of portable space heaters and vacuum cleaners want to sell their products to the general public they need to use the a standard NEMA 15 amp plug. In doing so the continuous FLA of their equipment must be rated for 12 amps or less. That is if the equipment is safety Listed. Other wise it could be a fire hazard.
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