1- How does a typical street lighting circuit look like? (for 230V/50Hz, with details)

2- Without having the network plans or knowing anything about the topology of the circuit, is it possible to map out the circuit by a series of measurements at the junction box of each post?

My idea is to:

  • adding a known load to each post
  • turning ON and OFF the load
  • measuring the current and voltage at that point
  • then calculating the voltage drop
  • finding the topology, etc. with a series of calculation

Can I find the topology by measuring voltages, phases, ect?


If you have a three-phase overhead supply to your house with street lights on the same circuit, these are reticulated with an extra pair of wires runneng through the neigbourhood. Exche streetlight is connected between the live and neutral wires.

The supply originates at a MV supply transformer and a light sensitive or timer control circuit drives a contactor that supplies up to about 100 streetlights.

The impedance of the copper supply wires are know as well as the distance between poles and the wattage of each lamp. (New 70 W high-pressure sodium luminaires were installed in my street less than a week ago, replacing mercury vapour to save electricity :-)

It should be easy to trace the circuit from the supply transformer and draw the circuit diagram to calculate the voltage drops.

  • \$\begingroup\$ where are you? Around these parts, it seems that new street lights tend to be LED installations, replacing the sodium ones, for reasons of efficiency, and light quality. The folks involved in that business don't seem to be as sure about reliability – they do believe the LED lamps will last a long time, but they're simply lacking the decades of experience with sodium. \$\endgroup\$ Mar 18 '17 at 11:15
  • \$\begingroup\$ I also wondered about that. I will ask around to find out why not LEDs. \$\endgroup\$
    – skvery
    Mar 18 '17 at 11:27

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.