earth electrodde

[Lectrician]

Yep, always do the MEB's in 10milli.

I would also always look to provide PME if it would be available - the cost of this verse a rod and 100mA RCD is actually cheaper.

 

[Adam_151]

2.5mm² protected against corrosion and mechanical damage (seems rather small though imo)

I'd think 2.5mm should take 240A for long enough to take out a RCD, especially given that it should be starting from cold

anyone fancy calculating the adibatic for the trip time of a type S rcd, a starting temp of room temperature, the limiting temp of PVC insulation and an EFLI of 1 ohm?

Taking K to be 143 (70 degree PVC, starting from cold)

K²S² = 143² x 2.5²
= 20449 x 6.25
= 127806.25

240volts over 1 ohm = 240 Amps

I²t must be a max of 127806.25
t must not exceed 127806.25/(240²)
=127806.25/57600
= ~ 2.2 seconds which is AFAIK, far greater than the trip type on an S type RCD
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