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I have been reading a little about bonding and outbuilding supplies and have just had a thought.
My father has a metal framed greenhouse with a socket inside supplying a heater.
The heater is metal and the socket is metal clad.
The supply is TN-S and I am not sure of the loop impedance, I can measure it tomorrow.
From what I have read I am now of the opinion that this metal frame should be bonded back to the MET in the house.
I can use the adiabatic to work out the size of bonding conductor.
The greenhouse is made primarily of glass but with a steel frame.
The other thing is the supply is an underground lead sheathed TN-S cable that runs about half a mile to a transformer on a pole in the field out back.
There is so much of the metal sheath connected to true earth on the long run back that it kind of acts like an enormous earth plate if you know what I mean.
The lead sheath is then connected to the transformer which itself has a long earth cable going into the ground.
Do you think this greenhouse needs bonding?
Thanks.
P.S. one more thing, the ground is clay and very damp and soft, if a TT were installed I would imagine a very low reading could be obtained.
My father has a metal framed greenhouse with a socket inside supplying a heater.
The heater is metal and the socket is metal clad.
The supply is TN-S and I am not sure of the loop impedance, I can measure it tomorrow.
From what I have read I am now of the opinion that this metal frame should be bonded back to the MET in the house.
I can use the adiabatic to work out the size of bonding conductor.
The greenhouse is made primarily of glass but with a steel frame.
The other thing is the supply is an underground lead sheathed TN-S cable that runs about half a mile to a transformer on a pole in the field out back.
There is so much of the metal sheath connected to true earth on the long run back that it kind of acts like an enormous earth plate if you know what I mean.
The lead sheath is then connected to the transformer which itself has a long earth cable going into the ground.
Do you think this greenhouse needs bonding?
Thanks.
P.S. one more thing, the ground is clay and very damp and soft, if a TT were installed I would imagine a very low reading could be obtained.
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