Standardisation of Mains Voltages

[turretslug]

Originally Posted by emeritus

Things were different by the Edwardian era: by 1905 the manufacture of GEC's "Robertson" lamps included a semi-automated step of an operative immersing the mounted filament in bath of liquid benzene and applying current to make the immersed filament glow.

That's fascinating and ingenious- imagine the paperwork now though, a modern H + S rep would turn blue and fall over!

[emeritus]

The book mentions that, if (when!) the benzine, which was in an open container, caught fire, the operative only had to pull down a hinged cover to extinguish the flames! The "flashing" line was on the top floor of one building and there was an open bridge at the same level to an adjacent building for use as a fire escape.

I believe one reason for the practice of double-pole fusing may have been to allow each circuit to be isolated independantly for carrying out insulation tests. The 1893 GEC catalogue includes examples of some typical wiring installations and, while they have single-pole fusing, the fuse is in one leg and the switch in the other. This was stated to facilitate insulation testing of the individual circuits (no doubt using one of the catalogue's "meggers" that could be hired out by the day if you didn't want to buy one).

[Cobaltblue]

As this is one of Many threads on this subject and seems to be diverging somewhat it's time to flick the big off switch.

Cheers

Mike T