Mike, thanks. For the life of me I could not remember “Duspol.”
www.benning.de/alt/englisch/eduspols.pdf www.trueshopping.co.uk/product.php?...=5&pn=Draper+Duspol+S+Voltage+Tester “…Indicates The Phase-sequence Direction of a Three-phase Main Provided The Neutral is Earthed.”
That may mean: two phases and a neutral, which is a valid phase-sequence test.
