All the portable generators I have seen have the neutral and ground bonded in the generator.
Typically, they use a 4 wire circuit from the generator to the transfer switch. The popular UL approved transfer switches don't switch the neutral. Installing them according to instruction, it seems to me that while the generator is supplying power to the circuits in the transfer switch panel, there exists two points of bonding, one in the genny and one in the HO's panel.
There are thousands of these installed.
Q1: I don't see a safety issue with having the two bonding points, in fact, I would see a safety issue if the bond in the generator was removed. Am I missing something?
Q2: Since the transfer switch is a UL listed device, if it is installed according to instruction does that negate the single neutral/ ground bond requirement of the NEC?
There is not much to the installation of these transfer switches. There is a pair of conductors from each switch (typically 6 switches) that intercepts the desired circuits and are connected in the panel, and one neutral and one EGC going from the panel to the transfer switch. From the transfer switch, 'house wiring' (manufacturers words) connects the transfer switch to an outside receptacle box (supplied with transfer switch) and a cord with L1430 ends on it (also supplied) that goes from the outdoor box to the L1430 receptacle on the generator.
Q3: Is the above installation code compliant for use in a residence? If not, what, exactly, is the violation.
Q4: If the above installation is NOT code compliant, what would need to be changed in order to satisfy the code's requirements?
Here is a typical transfer switch unit: http://www.homedepot.com/h_d1/N-25ec...&storeId=10051
And, in for the case in question, this generator (labeled that the neutral and ground were bonded in the genny) would be used: