We have a 3-Phase AC Electricity Generator (19KW) which comes with tires for ease of transportation, even though it requires a crane for lifting.
We have it installed in such a way that its main body is sitting on concrete blocks which are directly attached to the soil/earth below them without any insulation in between and the rubber tires are free.
Do we still need to connect the Ground terminal on the Generator to the earth below it? It would appear that since the terminal is connected to the body of the Generator and the Body has a direct connection to the ground by virtue of it resting on the ground itself there would not be any need for that but it was advised that the Cement blocks in between break that connection.
We did act upon the Electrician's advice and he did ground it like he said it was supposed to. This question is just for learning how important that was.
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