Hi.

So, is there a difference in telling the wattage of MV lamps in U.S. and Europe. So if I buy U.S. streetlight wich would have, let say 175W MV lamp. What Wattage european counterpart would have 125W?

I tried to search but could not find any topic so could somebody make list of counterparts?

For low wattages the selection is different between US and EU, the smallest common is 50W and the next one 250W and the biggest EU i've seen is 400W, same spec as US.
For retrofits, you should select a ballast with closest impedance:
US MV lamp => EU ballast
75W => F58T8 (~0.65A)
100W => SON/MH70W (0.9A into 130V lamp)
175W => SON/MH150W (1.4A into 130V lamp)

Of course, ignitors shall not be connected.

Damn. thats no good. Why it have to be soo complicated. 150W Son ballas will cost about 55euro(74 USD). while normal ballast for 125W merc only 20euro(27 USD). Do those U.S. lamps use different base too? I gues I just have to instal 125W E.U. merc and ballast.

Damn. thats no good. Why it have to be soo complicated. 150W Son ballas will cost about 55euro(74 USD). while normal ballast for 125W merc only 20euro(27 USD). Do those U.S. lamps use different base too? I gues I just have to instal 125W E.U. merc and ballast.

SON chokes (alone, not full ready-to-use ballast assemblies) are sold here (e-light.cz - they do have english translation web) at about CZK500..700, what's about 19..26Euro (if it is still 27CZK for 1Euro, it's changing quickly up and down in recent time)...