I’ve just had a new house built in Atlantic Canada. This morning I noticed a bit of a tingle from my coffee machine when I touched it with wet hands. The machine has a grounded (3 pin) plug and I checked - it has 0V between the parts I touched (the entire metal outer case) and the ground socket in the outlet. So, I got curious and did some more measurements. It turns out there is 20V AC (and about 300mV DC) between the ground in my outlets and me when I’m standing on my floor (sealed concrete slab) with bare feet.
I assume this isn’t good?
I’ll be calling the electrician that wired the house in the morning, but I’d appreciate any insights you might have.
When I said 6mm² it’s because of the distance, you want more copper to get less resistivity between both grounds; your water pump probably run on 1.5 or 2.5² which isn’t much - but by all means, please ensure that pump is grounded!
Also because IRL I run elec for open-air festivals & with great responsibility comes great paranoia ;)