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What does?Needs to be 25.0 if your are burying it the ground on an 80A protective device.
Edit
You mean the swa
Discuss Suggestions for best way to wire underground supply please in the Electrical Wiring, Theories and Regulations area at ElectriciansForums.net
What does?Needs to be 25.0 if your are burying it the ground on an 80A protective device.
As it's a new build I doubt you will need to provide a protective bonding conductor to the water as the incoming supply externally will be in plastic but you'll have to seeYes, domestic, 10mm bond to gas/water - thanks for checking though!
why?Needs to be 25.0 if your are burying it the ground on an 80A protective device.
Just trying understand - Table 4D4A for direct buried at 0.7m, ambient 30, ground ambient 20 and conductor 70 is 78A. So question is, why pick 30 ground temp to further derate to?16mm swa buried is only 78 amps ambient temperature 20 degrees and that's without applying the 0.9 correction factor as cable is buried for ambient temperature for 30 degrees plus any other factors like depth etc
0.9 is applied where overload protection is required and prevents the cable going over temperature when overloaded.Just trying understand - Table 4D4A for direct buried at 0.7m, ambient 30, ground ambient 20 and conductor 70 is 78A. So question is, why pick 30 to derate to?
fit a fan.What about the part of the cable that comes out of the ground?
That part would be ok - 89A clipped direct or 97A in free air ?What about the part of the cable that comes out of the ground?
Based on 30 degrees tho yes?That part would be ok - 89A clipped direct or 97A in free air ?
Only if you pay my electric billas an experiment, try shoving 100A down some 16mm for an hour. then measure the temp. of the cable. if you read >40deg.C. then your temp gauge is wrong.
Well it errs on the side of safety but I didn't write the regs , send any complaints to jpel/64 hawe not in the sahara . not even spain. 30deg. my arse. we'd all be like essex boys at that temp.
Yes, 4D4A is for ambient air temp of 30. Still thinking ...Based on 30 degrees tho yes?
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