What is the maximum lenght of your feeder on streetlight from the KWHmeter? Using 230V; single phase
given the ff data.
a)250W metal hallide - (what is the max/min spacing and height)
b)23W compact flourescent lamp( mostly spherical parklamps)
any innovations?
Well, the astronomy guys would really like it if you use low-pressure sodium lights, because they can filter out the sodium line. Anything resembling a white light pretty much blinds telescopes by lighting up the night sky.
I don't know if that's the sort of "innovation" you were looking for.
We use streetlights at 230 - 240 Volts in New Zealand.
They are connected in strings via a contactor and 32 A mcb.
Substation control via lightcell and loadshedding relay drives contactor, string of 10 to 15 lights 250 Watts etc.
Cable runs in new areas are 500 to 1000 metres with 10 mm² neutral screened cable, feeding about 15 poles ( In 15 Ampères )
In older areas of town 2.5 or 4 mm² cables were run up to 600 metres in length feeding 6 or 7 lamps HPS 85 Watts. In 3 to 4 Ampères.
If I'm understanding your question...
The minimum/maximum distance is calculated in relation to the height of the poles and fixtures. You need to define one of the variables in order to calculate the other, and all of this information should be based on the parametric specifications of the specific fixture.
Most lighting manufacturers provide this information for each fixture they have on the market for the design questions you are putting fourth in this forum. Often this information is available on the manufacturers web site, in the form of a .pdf file that can be downloaded. If the job is big enough, the manufacturers will usually be happy to assist you in design of your installation.
250W Metal Halides, in my experience, are usually coupled with 15'-20' poles. Commonly 20'.
A 23W CFL "lollipop", or spherical type globe fixture, is rarely placed above 10', as the low light output would be useless above this height (the fixture would glow, but not project useable path lighting).
Once you figure out how many fixtures will be needed and the total length of the run, total amperage, etc, you can calculate wire size, power requirements, number of circuits, control options, etc.
Good Luck!
Hi Solar P.
I forgot where i read it... but is there a study that white light is not prone to rosd accident?..
I don't have any links, but I recently read an article about the town of Holly, Colorado USA that was wiped out last year by a tornado. Town being rebuilt, and the power supplier XCEL is donating LED street lights. XCEL dosn't even supply power to this area, yet they are helping out.
A google search should turn up new ideas for streetlighting.
Rick Miell