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Conventional Fixtures 28V 250 Watt PAR lights?

Discussion in 'Lighting and Electrics' started by koimystic, Dec 11, 2008.

  1. koimystic

    koimystic Member

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    I took some pars home from my youth room the other day and the bulbs in them are 28 volt 250 watts. Those lights are actually made for aircraft landing gear. I hooked one straight up to 120 volts and it popped, another to 12 volt car power supply and it worked any idea why these bulbs would be in par fixtures?
     
  2. n1ist

    n1ist Well-Known Member Premium Member

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    PAR lights were originally aircraft landing lights (ACL). Aircraft power for some reason is 28V.
    Use 4 in series on 120V.
     
  3. David Ashton

    David Ashton Active Member

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    And the reason is, that as the voltage decreases and the current increases and the filament gets thicker, the filament can run hotter and be more efficient, this is why your car headlight [60 watt] is much brighter than your household 60 watt lamp.All things being equal.
     
  4. Van

    Van CBMod CB Mods Premium Member

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    Those aren't PAR's they are ACL's they are designed to be wired in series, 4 in a row 28v X 4 = 112v. Typically they are wired together in series on an "ACL bar" without indiviual plugs on them. They are really designed to not be confused with each other. An ACL lamp is a small glass lamp that plugs into a creamic base that is attached to a < usually> aluminum reflector. The reflector is designed to mount in a PAR can. A PAR Lamp is a glass enclosed envelope with, typically, a ceramic base with two 1/4" male spade or tab connectors on it. it is designed to fit directly into a Par can.
    Plugging an ACL directly into 110 - 115 v will cause a single one to go Pop.

    PARs are pars and ACLs are ACL's They did not grow out of each other.

    ACL's were adapted to use in PAR cans since they are extremely bright and with no lens, create a very concentrated beam. In my expirience they are mostly used as; Audience Blinders, punch / accent lights, and in some cases as a stand in for an older style fixture know as a BP or Beam Projector.
     
  5. gafftapegreenia

    gafftapegreenia CBMod CB Mods

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    Good man Van, I must disagree with you.

    Firstly, the PAR lamp made it's first appearance as the "sealed beam" automobile head lamp. For a period in history, the US government mandated that all autos used sealed beam head lamps.

    An ACL lamp is a PAR lamp. PAR, as we know, stands for Parabolic Aluminized Reflector. The traditional PAR lamps we use in stage lighting are PAR 16, 20, 38, 46, 56 and 64.

    Now, an ACL can be considered a "special" kind of PAR lamp. ACL lamps are low voltage (28v for PAR 64 size) lamps with a short, thick filament. This allows for a near ideal point source, thus give an intense, long range beam. There are two common types of ACL's we use, the PAR 64 variety, known as commonly as ACL's, and the PAR 36 variety, commonly known as either pin lights, rain lights or disco ball spots. Groups of 4 PAR 64 ACL;s will be used for "ACL Bars", and various sized arrays of PAR 36 ACL's will be used for audience blinders.

    The biggest distinction is that the low voltage pars, or ACL's, use screw terminals for their wire connections, and thus need a safety screen on the back on the PAR can, whereas a regular line voltage PAR uses a ceramic mogul base.

    What I think you are thinking of are the old "Ray Light" kits. These were intended to be low cost alternatives to PAR lamps. They had a separate reflector and used a DYS lamp.
     
  6. koimystic

    koimystic Member

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    Thanks for the help everyone. I sure am glad I found this forum!
     
  7. Van

    Van CBMod CB Mods Premium Member

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    Yep, You are correct I got the ray light kits stuck in my brain.
    However, I stand by the rest of my post in the sense that it is a mis- characterization to say:
    "PAR lights were originally aircraft landing lights (ACL). Aircraft power for some reason is 28V."

    PAR lights, in the theatrical / production world were never origianlly 28v. ACL's, PAR's, Train headlights, are all sealed beam lights, many are pars, but they all grew up differently.
     
  8. gafftapegreenia

    gafftapegreenia CBMod CB Mods

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    Yes well I can't argue with that, but they do stem from a common ancestor.
     
  9. ship

    ship Senior Team Emeritus Premium Member

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    Sealed Beam Lamps would be the general classification for most low voltage PAR lamps - used for tractors, loccomotives, aircraft, the landing lights for them, Autos or what ever providing low - other than line voltage to the lamp. The "ACL" term is more one our industry uses in general just as "Leko" is a term used in general.

    Lots of range in size voltage, wattage and beam spread out there for lamps designed for all kinds of purposes besides use for the aircraft industry. Believe a PAR 56 size was something that came out of like 57' Chevy type technology as a lamp size by the way as further info.... (not confirmed or for sure beyond what I think at one point I heard.)

    Still back to reality, even a really really close to MFL lamp at 115v/1Kw which has to be one of the most powerful PAR lamps on the market that's still a filament lamp type. The #4555 is 600,000 candlepower at 11x20 degrees in beam angle - over five times that of a FFR in output and just as much output of the 28v/600w VNSP #4559 "ACL" less commonly used on stage but the most powerful ACL lamp once used on stage/rock for the highest punch. Granted the #4555 is only a 25 hour lamp and costs well over a hundred dollars per lamp which no doubt is why they don't get used more, but there really is a huge range of lamps out there - sealed beam lamps range in all sorts of ways - this including beam spread.

    My un-latest updated file on PAR lamps in general alone - line or low volage on the same file based on size than wattage is 1,409KB of 8pt text on a table. That's a lot of PAR type lamps to choose from and mostly in other than line voltage. Lots of stuff out there including PAR 46's WFL lamps.

    By the way, the smallest PAR lamp is a PAR 14. Osram and Bulbrite both have a 35w PAR 14 flood on the market.
     
  10. derekleffew

    derekleffew Resident Curmudgeon Senior Team Premium Member

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    Did the 1957 Chevrolet use a 6V or 12V electrical system? 25114 - Specifications - GE Commercial Lighting Products OR 18519 - Specifications - GE Commercial Lighting Products. In the 1980s, I sold the GE PAR56 "ACL" Locomotive Headlamp (may have been: 20122 - Specifications - GE Commercial Lighting Products) to one of the R&R Lighting companies in the area. I also built a "curtain" from 21x PAR46 6V, 30W lamps (plastic "cans" on 18" centers) all wired in series. Was glad I didn't have to maintain it.
     
  11. Van

    Van CBMod CB Mods Premium Member

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    This is another good example on the true depth of incredible info that can be garnered her on CB. I love this place!
    However, we diverge from something that has been truley bugging me about this post since I first read it;
    Koimystic.....What were you doing taking ACL's home to play with in the first place? Not to be rude but, "Hey, I don't know what this is....I think I'll plug it in..." is a great way to get killed.
     
  12. derekleffew

    derekleffew Resident Curmudgeon Senior Team Premium Member

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    Well, as long as we're picking on the poor guy... [user]koimystic[/user], you took some PAR CANS home and they had LAMPS in them. The fixtures should have had non-standard (or clearly-labeled) plugs. You should have also found an ACL Harness, which connects the lamps in series to one another, allowing the four 28V lamps to operate on a 120V supply.
     
  13. David Ashton

    David Ashton Active Member

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    Yes that is extremely stupid and dangerous, exactly what I used to do at that age.
     
  14. LightStud

    LightStud Active Member

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    Yes, David, but aren't you glad we're older, and (hopefully) wiser now?
     
  15. ship

    ship Senior Team Emeritus Premium Member

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    Was also thinking this but errored on the side of perhaps they were thought to be normal lamps and say going outside in a protective housing persay. But good point - granted I have over the years broken this rule but only by way of careful lamping, wiring and control.

    Yea, for instance some inkies light my living room on a dimmer, they are lamped at 35 watt on the other hand.

    Further points... yep, older and wiser now for all involved. Done some really spectacuar things over the years including a FEL inside a small coffee can that was poked with holes so as to make a star projector. Filament was a bit large to efficiently project stars and the lamp socket plus wiring given a certain lack of ventilation melted down in a specacular way that I learned from but it was a learning experience in something I won't do again.

    What's hoped in not slamming but pointing out concepts and ideas is that those of the next generation learn from those that already made the mistakes or learned from those before us at times making the same or better mistakes with electricity so as to go onto bigger and better mistakes we hadn't tried yet and or bigger and better ideas and concepts we had not thought of yet.

    Been a few years that the Leko prep department went thru a rash of ACL lamps in the PAR 64 fixtures by those prepping them. Remember a few instances over the years when they would blow up lamp by lamp until they detected a theme and came to see me eventually. These days possibly even one that once blew up a lamp now runs the department and ensures they have the right lamp in the fixture before they test it and we don't blow up ACL lamps any longer. Even ensures the ACL bars get powered up by a dimmer instead of just turning them on by way of switch. One hopes she is explaining why this is the policy in those learning getting the education without needing to learn by doing. Again a passing on the knowledge type of thing, this in addition to a well enforced policy type of thing.

    Who let the fixtures out the door on loan and didn't ensure the correct lamps in them seems just as at fault as the end user that didn't know any better. This all beyond stage lighting equipment not designed for home use concept.
     
    Last edited: Dec 12, 2008

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