In article . com,
wrote:
Was selling my cement mixer yesterday, and when selling, tried to
show it to the buyer working in the shed. when plugged in and
switched on, it just tripped the RCD. I reset it and it happened
again. Finally when connected to the house supply via extension
lead i was able to show him it working.

Was it a 2-wire extension cable?

The lack of an earth wire could have masked an earth
leakage fault that really was present in the mixer.

If that was the case then mixer may be dangerous and
it might be prudent to contact the buyer asap.

--
Tony Williams.