i actually had one of these same chokes i saved about 20 years back out of another derelict column, i know for a fact they are revo made, anyones guess what the tappings are, pot luck i recon. think this dates from the 1940's as the column was very early

Looks like a 40s choke to be honest maybe early 50s! The different taps are probably from before the grid was standardised across the country where we had 230/240/250V?

took a guess on which ones to use, wish id left the old cables still in the clean one, i would have known for sure then.

good old GRELCO bakelite terminal block, i have a number of these blocks, they did different sizes. Old BLI fittings used double ones

Its got a cast iron frame around the windings !

You gonna keep or chuck!

Your normally fairly safe with the outter 2 taps. I always look for marks on the screws as it shows they have been used

Wonder what the power factor loss is on the oldies?, be interesting to put one on a watt meter?