Radio set No 11 power supply leads.

[Chris Suslowicz]

Originally Posted by Mike Kelly

I disagree . 240 volt domestic power lines are lethal and dangerous . Mike

I won't disagree with you on that statement, but I was using the power distribution definition of "Low Voltage".

(From Wonkypedia, so likely to be U.S. biased)

Overhead power transmission lines are classified in the electrical power industry by the range of voltages:

Low voltage (LV) – less than 1000 volts, used for connection between a residential or small commercial customer and the utility.
Medium voltage (MV; distribution) – between 1000 volts (1 kV) and to 69 kV, used for distribution in urban and rural areas.
High voltage (HV; subtransmission less than 100 kV; subtransmission or transmission at voltage such as 115 kV and 138 kV), used for sub-transmission and transmission of bulk quantities of electric power and connection to very large consumers.
Extra high voltage (EHV; transmission) – over 230 kV, up to about 800 kV, used for long distance, very high power transmission.
Ultra high voltage (UHV) – higher than 800 kV

Low Voltage in the U.K. was the overhead poled supply running alongside residential roads, with four parallel wires supported on insulators. This was a 3-phase Y connected supply (240/250 volts phase to neutral, 415/440 volts phase to phase) and houses were connected to each phase in turn while commercial buildings requiring more power could have a 3-phase feed (farms, garages, etc.).

Medium Voltage is 11 or 33 kV, again on overhead poles (rather taller, and usually with the wires horizontally spaced on a crossarm) and Delta connected to remove the need for a neutral connection.

High Voltage is on the very tall steel pylons. (Usually 132 kV and above, for long distance transmission.)

Chris.