the neutral and ground are bonded at the main panel because there is a path to the ground rod. they are not tied together at the sub panels because the ground wire is solely used as an insurance policy.
Do you bond the neutral and ground in a transformer?
Transformers or other separately derived systems [250.30(A)]. To provide the low-impedance path necessary to clear a ground fault from the separately derived system, you must bond the metal parts of electrical equipment to the grounded (neutral) terminal (XO) of the derived system.
How do you neutral bond a transformer?
Quote from the video:
Quote from Youtube video: So beside grounding this we want to make sure that the secondary side is all bonded together and connected to the system. So this system bonding jumper is how we bond.
Why neutral is grounded in transformers?
Neutral transformer grounding serves as a permanent and continuous conductive path to “earth” with sufficient ampacity to carry any fault current, sufficiently low impedance to limit the voltage rise above ground, and facilitates the operation of the protective devices in the circuit.
