A 46,000 sq foot building site has the steel skeleton up with the 2nd floor deck serving as a porous roof. They are using corded drills to screw pre formed panels for the walls. 6 to 8 drills are plugged in at one time. 4 duplex (GFCI) outlets are wired in a wall by the entrance. A 20 amp breaker is on the outlets. They are running a 50 ft cord with a spider box. They are running 5 100 ft cord in series to reach men on the far wall. The spider is also GFCIed. A proven gfci tester will not pop either GFCI in the cuircuit. All cords are 12 hard service. Aside from wiring the building is there a good solution to this long run? The GFCI TESTER still works on regular GFCI outlets but will not pop this one with 2 GFCIs in series?