Yes and no. The system is grounded at the utility transformer and also at each separate structure. The NEC definition of grounded means connected to the earth. Receptacles and other metal parts of the electrical system are bonded to provide a low resistance path for the fault current to the return to the source via the neutral. All of the equipment grounding is accomplished by the main bonding jumper (MBJ) that bonds the neutral to the cabinet at the service.
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From what I understand, There are 2 power wires running out of the transformer. 3 wires running to the home. The 2 insulated wires from the transformer. 1 bare wire which is the ground wire. But that ground is for the service disconnect enclosure. Both insulated wires each carry 120 volts out of phase so the difference is 240 volts for appliances.
I dont recall ever seeing that before, thanks for the education…
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You’re correct about the number of conductors, a typical residential drop has three conductors, two insulated ungrounded and one bare neutral (or grounded conductor). The bare conductor is used a support for the drop which is stranded aluminum with a solid steel core. Every metal part that is upstream of the service disconnect is connected to the neutral since there are no equipment grounding conductors on the line side of the service disconnect.
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