In 1949 a lighting dimmer was invented that used 3 phase, phase-controlled, half-wave rectification by means of 3 thyratrons. Its output was pulsed DC and was very effective in dimming incandescent lamps. It however was a prodigious generator of harmonics with damaging neutral currents, and had a poor power factor even at full output.
Nowadays such a product would be banned by supply authorities and product regulation, but things were much laxer then. However problems caused by large DC loads such as mercury arc rectifiers on AC supplies, would have been experienced by many practitioners in the 1950s. Can anyone point me to UK standards or custom and practice from that era that might have been known and gave guidance on the problems caused by rectifying AC loads?
