It's called 'Niedervolt', not 'Neidervolt'. 'Nieder' means 'low' in
German, whereas 'Neider' means 'envier'. So you where asking for an 'envier
voltage'
unit
A 'Niedervolt-Scheinwerfer' generally contains a
transformer to transform the 230 volt input to the 24 volts that is
fed to the lamp. They generally use a
parabolic reflector and can produce very narrow beams. Dimming tends to be a little
bit slow with these units.
Even in Europe this is considered an outdated type of
fixture. Some theaters still use them because they have them in their inventory, but they would probably not invest in new units of that type. Maybe your light-designer is a traditionalist.
As a replacement, anything that can produce a very narrow beam will work.
@pyrotechnician and
@SamSam This would make sense in terms of the 1990 full bore productions of Les Miz.
The R & V beam projectors included an outboard accessory
transformer with multiple primary taps, or dual primaries, to accept powering from 120 or 240 volts; either via a tapped primary or dual primaries to be connected in series or parallel.
(Again, three decades ago, my memories are more than a little clouded; my time with 'Miz I was parachuted in for six weeks when IA 58's operator injured his back after an evening performance.)
I arrived home from vacation to find a voice mail on my old-fangled dual cassette answering machine asking for a
call back ASAP if I could make myself available for an unspecified period of time 'til IA 58's Jim Brett returned from hospital.
I'd worked with Jim for years in Stratford while Jim was at the Avon and I was in the Festival
Theatre main
stage.
Jim's a good guy, the money was GREAT, no rehearsals, 8 performances per week; how could I say no?
When 'Miz ended, Jim and I both toured with Mirvish's British / Canadian co-pro of 'Buddy Holly The Musical' all the way to Broadway's Shubert.
For six weeks, I sat behind a
Strand Pro-Palette on one of the SL intermediate floors next to the
turntable operator with the two SL R&V beams mere feet in front of me. The R&V
spot op' on the SL side was a member of IA 129, my Hamilton, Ontario home local.
With IA 129's Jim Langham in front of me, as well as serving as my ride to and fro' Toronto for six weeks, I learned much about the R&V Beam Projectors while having ZERO to do with their installation and / or setup.
Bottom Line: I remember a lot about the R&V's but had nothing whatsoever to do with them other than supplying their raw, non-dimmed,
power.
Forgive me for not being 120% up to speed on their exact details.
In either case, the secondary provided (from memory 24 VAC) a reduced
voltage to
power the specified
incandescent lamp.
Dimming response would be understandably sluggish due to thermal inertia in the comparatively short, coarse, low
voltage filament; sluggish but considerably more resistant to failure due to mechanical / handling vibrations.
In North America, 120 volt Variacs were used to
power the
transformer's primary(s).
Toodleoo!
Ron Hebbard