Huh?
if its a portable GFCI (any GFCI which is cord and plug connected, or on a cord reel or pendant) it has to have open neutral protection. With a standard GFCI, if the neutral is lost the GFCI cant function, and will not trip on a ground fault. GFCI with open neutral protection will not energize the load side if a neutral is not present.
from here
http://ecmweb.com/mag/electric_think_gfci/
"When receptacles used for temporary power are a part of the permanent wiring of the building, then the Code requires that "GFCI protection for personnel" be provided. In other words, the permanently installed receptacles are not required to be GFCI protected, but the people using them are. GFCI plugs or portable GFCIs are frequently used for this purpose.
UL has very specific requirements for cord-and-plug connected GFCIs. It is not proper (and is a violation of the listing of the GFCI) to make up cord-and-plug connected GFCIs by installing a GFCI receptacle in a handy box and connecting a cord through a knockout.
The special requirements UL imposes on cord-and-plug type GFCIs recognizes that they can be plugged into receptacles or cord connectors that may not have a reliable neutral connection. If this should occur, the GFCI trip coil, which needs a neutral to operate, will not function and the GFCI tripping mechanism will remain latched closed, even if a fault is present. Therefore, cord-and-plug type GFCIs typically have normally open relays as their interrupting mechanism (or in combination with a latching mechanism) that will prevent the GFCI from being energized if an open neutral condition exists.
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