Earthing, Metals and different voltages during faults Discussion ThreadEarthing, Metals and different voltages during faults Electrical Advice
Hello,
I have a few questions on the image I have attached:
I am proposing to put a small electrical metal box within a larger electrical metal box but having them both physically isolated via a non-conductive plastic. The larger electric box would have electronic equipment that is powered from a 240v source protected by an RCD and stepped down to ELV DC. All the DC driven equipment within the larger metal box will be connected to an earth bar placed within the larger box which will also be connected to an earth mat part of a building. The smaller box would also have equipment from the same 240v source and protected by an RCD but stepped down to 18-20v AC via a Transformer unit. The transformer unit would also be metal and the earth cable from the 240v would be connected through the metal TFU and connected to the smaller metal box which the TFU is placed within. Note both the metal boxes shall be isolated via a non-conductive material.
what would be the major issues with this arrangement?
During a fault scenario if a person was touching both the small metal box and the larger metal box at the same time would this cause a serious hazard? considering once is AC and the other is DC.
Any feedback would be great
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Earthing, Metals and different voltages during faults for the original thread on Electricians Forums
Hello,
I have a few questions on the image I have attached:
I am proposing to put a small electrical metal box within a larger electrical metal box but having them both physically isolated via a non-conductive plastic. The larger electric box would have electronic equipment that is powered from a 240v source protected by an RCD and stepped down to ELV DC. All the DC driven equipment within the larger metal box will be connected to an earth bar placed within the larger box which will also be connected to an earth mat part of a building. The smaller box would also have equipment from the same 240v source and protected by an RCD but stepped down to 18-20v AC via a Transformer unit. The transformer unit would also be metal and the earth cable from the 240v would be connected through the metal TFU and connected to the smaller metal box which the TFU is placed within. Note both the metal boxes shall be isolated via a non-conductive material.
what would be the major issues with this arrangement?
During a fault scenario if a person was touching both the small metal box and the larger metal box at the same time would this cause a serious hazard? considering once is AC and the other is DC.
Any feedback would be great
Earthing, Metals and different voltages during faults for the original thread on Electricians Forums
