The terms ACL, Pinspot and Sealed Beam Lamp are all for the most part the same or often confused in terminology. A Pinspot can be a type of low voltage ACL if talking about a PAR 36 lamp and both are industry terms for Sealed Beam PAR lamps just as a CDM lamp might mean something for those using a normally G-12 based 150w/95v arc source with ceramic capsule. A ACL or Pinspot can however be amongst many sizes and type of PAR lamp all of this class of low voltage such the SBL general term for this class of lamp covers and is in all three of the examples given a form of one or another but unknown for sure which type.
Just as there is nothing magic or real advice given in what you hear on “This Old House” when they say - (what type of lamps are these, ..these are halogen lamps....,) What a great help lack of help that was, just go to your home center and ask for one of them halogen lamps of which even the ETC S-4 or VL-1K qualifies for just as well as your Mag Light or some unspecific under-counter light fixture. In calling something a Pinspot verses ACL that’s brighter what specific form of Sealed Beam lamp used is the detail important fpr discussion. Even within a wattage and voltage type, there can be different beam spreads just as there is more than one type of 120v/1Kw PAR 64 lamp out there. Install a #4511 lamp into a pinspot and it will work just as well but have much less intensity given it’s wider trapezoid beam spread.
ACL’s in term these days for a rock and roll usage of it are normally the 250w/28v PAR 64 #4552 lamps, but can be just about any lamp that might have had a purpose at an airport at some point as opposed to in a car, tractor or stop light in original use amongst many other low voltage lamp uses. The ACL term is much like the term Leko in usage for a number of types and brands of fixture or in this case lamp. This is where the “Aircraft Landing Light” term no doubt began but not where it ends for our usage. Yes a Ray Light will be a type of reflector inserted into a PAR can but between 300, 600 and 800w lamps available and a few beam spreads of reflector it’s also a general term as opposed to AR-111 type of lamp that can also be available to do the same thing as a Ray Light, only in low voltage most often. An AR-111 lamp/reflector can also qualify as a Pinspot if not called a ACL or SBL but less falling under the term of those. In fact, given a 6v AR-111, you can replace one with your #4515. There is a 35w/6v AR-111 lamp that would probably work in a Pinspot. Given it’s four degree beam angle, it probably would also be more intense in focused beam.
Specific to a PAR 36, the 250w/28v #4596 is the typical PAR 36 “ACL” lamp for rock and roll use. Are you sure you did not forget a decimal point where wattage is concerned? Yep, the #4596 is going to be much brighter. Both mentioned PAR 64 and PAR 36 ACL lamps in differentiating them from a pinspot or SBL in general for our purposes are going to be used in series by way of wiring. This is normally four fixtures equaling about 120v as opposed to in a SBL or Pinspot where normally you are using a transformer for one or two individual lamps if not even two taps off a transformer for each of two voltages in tap and double filaments for a single lamp. Your low and high beams for a car’s headlight. A ACL than by term would be most normally used in meaning lighting system of a few lamps/lighting fixtures wired together for series as opposed to parallel or transformer based. The highly respected for effect and very expensive DHA Light Curtain in reality is nothing but a PAR 56 cyc light with ACL lamps in it. Big difference between a DHA light curtain and a sound system guy’s ACL’s yet they are both other than in lamp dia (PAR 56 verses PAR 36) used. By terminology, given a ACL fixture is normally something wired in series, those down under or in Euro who use two 120v lamps in series to get to 230v would also be even if using a FFS wide Flood 1Kw/120v lamp, it would be a ACL lamp for them at least.
A Pinspot type of lamp/fixture is better defined and more normally in usage what going to be also at times called a Mirror Ball Light - due to the Radio Shack / local DJ shop fixture normally sold with to light the mirror ball, but also at times used for lighting effect in your case. The normal Pinspot is always going to be a 5.5-6v lighting fixture at 30w. The #4515 is the normal lamp in use for them. There is a halogen upgrade pinspot lamp that eeks out a bit more output for the same life should you wish for more punch. Any SBL that’s halogen will normally get a “H” in front of it’s number code thus “H4515.” There is also other 6v PAR 36 lamps of 30w or less that your transformer based fixture could house and power up including some with a wider beam of light.
A Sealed Beam Lamp is the overall term for this type of normally low voltage PAR lamp of which there is literally at least 750 types amongst almost over 1,500 types of PAR lamp. Normally they are screw terminal and or quick disconnect based but not always either. GE has a excellent Low Voltage/Sealed Beam Lamp catalog out if you can find a copy which lists just about all of the lamps on the market of this class. GE Miniature & Sealed Beam Lamp Catalog, G.E. Lighting # 208-21121 (9/92)
Once you add a transformer to such a ACL lamp, it’s still often called for entertainment lighting purposes a ACL but only by way of this lamp is normally a ACL lamp type, even if the fixture has a transformer in it. I have a unknown brand of 6v/120w transformer based PAR 64 fixture. It’s using a ACL lamp and in fact the fixture probably is a ACL fixture. Yet it’s more a Pinspot fixture for our industry terms given the transformer based fixture, but could still be called a ACL given it’s lamp that might in airport use be in reality a ACL.
This just as you could do 20 #4515 Pinspot lamps in series and they would really be a ACL given the normal definition but still called Pinspot in type. On the other hand, If I say I have created a multi-lamp PAR 36 Audience blinder and ACL fixture, you know it’s probably going to have #4596 lamps for the ACL part of it and DWE or FCX for the audience blinder types unless specifically stated to be other lamps. If I say I have turned some Pinspots into Audience Blinders and ACL’s it’s more specific as to the type of lighting fixture used but still what lamps were used are fairly well given by stage hand terms. It also would be implied that in turning a Pinspot fixture into a Audience Blinder or ACL, that all transformers were removed and some were wired in series, the others in parallel. This much less in turning a Pinspot into a ACL or Audience Blinder, a 3" dia hole had to be punched out of the rear of the fixture and screened from touch so as to vent the higher wattage and more heat fixtures.
(And now we get very technical but hopefully informative.)
Let’s get back to your lighting fixtures/lamps in question. I expect that it’s 250w/28v #4596 PAR 36 ACL lamps you are considering to buy if called ACL lamps. There is nothing available in PAR 36 at 25w that compares to that of a pinspot in output. The absolute closest to this would be a Philips #27530-5 “25PAR36" in 30,000 Lumens but only a 2,5x3 degree bean spread a true ray of light but still not a match of a #4515 pinspot.
Four of the #4596 ACL fixtures will be wired in series to gain in this case 112VAC and be 1,000w per circuit as opposed to how ever many 30v lamps you use. Yea, you have a 250w or in actuality a 1,000w combination of low voltage lamps as opposed to a individual 30w lamp or how many you stack up and it’s going to be a wee bit brighter. Light on stage however if you have four lamps at 250w or twenty at 30w, the overall intensity will about balance out. Apples and oranges given different wattages and type of lamp system. Nope your individual lamp won’t be as bright as a individual ACL as it were, but put a bunch of them in and you have a equal effect given similar total wattages.
If you have 120v feeding the #4596 lamps, they will be not just be as bright as the lamps are expected to be by design or manual, but in operating over their rated voltage, the color temperature will go up by about 200K in color temperature and 5,399 Lumens more output. In other words as opposed to a 30w/6v lamp with about 3,000 in color temperature (Appairent brightness) and 55,000 Candlepower in light output of the 5x5 degree beam of light (or at best a 67,000 candlepower beam with halogen lamp for the H4515), you will be comparing it to a lamp with 12x11 beam that has 3,200K in color temperature and 155,400 Lumens in output at 28v/120v. Wider beam spread yet still lots more light output.
Pool 20 of your pinspot lamps into a similar in series type of wiring and you will possibly get just as much if not more intensity on stage.
(Brass tacks beyond looks bright:)
Sounds great doesn’t it for intensity?
Such rays of light are incredible for effect but not much use for other than that or especially normal usage in lamp life expectency or cost effectiveness.
For starters, just as on your X-Mass tree string of lights, blow one lamp in the series and they all go out. Losing four lamps in your lighting system could tend to be a wee problem if less than lots of them available. As opposed to 50 or 100 lamps in your string, you only have one lamp now going bad at a higher voltage left going to the remaining ones for a split second.
Consider this lamp in going bad. Ever notice how often as a lamp is about to go for a micro second, it’s incredibly bright? Such lamps in blowing become as if a arc source fixture. If even for a micro second, the filament is no longer working, instead it’s a arc of electricity within the lamp in jumping the broken filament gap. These lamps with both higher than rated voltage and high amperage applied to them will without a doubt get really bright for a moment. That jumping across a break in a filament in still conducting without the resistance of the filament if even for a moment means that one less lamp in series is deducted from your in series four lamp total voltage of the lamps in what they are given. If four 28v lamps are powered at 120v to be 112v, the three remaining 28v lamps are now in being provided three lamps of 120v in series have 40v applied to each individual lamp. This over-voltaging if even for a microsecond will tend to destroy them also. Once one lamp on the bar goes, they are all gone for all intensive purposes or dependability.
In other words, blow one Pinspot, it’s one lamp due to 120v by way of transformer feeding only one lamp. Blow a single ACL lamp wired in series and you not only loose all four lamps due to the break in the chain but will probably have to replace all four lamps should you want some form of cost effectiveness to what you rely upon working.
If you have a pinspot with #4515 lamp and transformer powering it up go out, you loose one lamp. Should during intermission you have a single spare lamp and it’s even used, what the heck, install it. What’s the worst that can happen but you have the lamp work for a while again and loose one. If you have a in-series lamp go out, you just lost all the fixtures wired in series with it for that period of time. Much less if DHA light curtain if not in some other than old timer stage hand application of “I have been putting used lamps or adding new lamps to my ACL’s for years without a problem,” you still now have different resistances within the filaments of the lamps and will not be prolonging life or be assuring other than constant reliability problems. Instead it’s proper to even if the rest of the lamps did not die, to replace all lamps in that series. This gets expensive especially since used lamps even if still working are useless now. Should you like a source for used #4596 or even GE #20575 DHA Light Curtain lamps, contact any large lighting company and you will get them really cheap given they have not instantly been tossed in the trash. Such used lamps are useless otherwise. Believe I have somewhere around 100 of this lamp waiting for the trash at the moment. Tours don’t want them, nor can I install a used ACL in a new fixture or even replace one for another.
Add to this the third factor for the voltage change formula. For every 1% change in voltage, light ouptut will change by 3.6%, Color Temperature will change in the same direction by 0.4% and lamp life will change inversely by 12%. Given a 112v in series set of lamps powered by 120v, you have a .00933 change in voltage. Not quite 1% but very close to it. Lamp life just went down by 11%. The 30w/6.4v #4515 lamp is rated for 100 hours. The 28v/250w #4596 lamp is rated for 25 hours in life and now once wired in series only expected to live up to 22.25 hours in life - less than 1/4 the lamp life of a pinspot. Given the lamp price is the same or more expensive for the #4596, it is very much not a cost effective alternative for lighting your stage. Neither lamp in fact is cost effective but unless you have a large budget, the ACL especially is not cost effective once you start replacing all four lamps if one blows.
Than let’s consider voltage spikes to your system. Stuff like for a spectacular effect you hit the bump button or turn off all but these pinspot lamps. Transformers in their slight lag time have an amazing effect on setting down sudden lightning spikes in current or other changes in the system loading by way of what’s reaching the lamp itself. Take away the transformer and wire all these lamps together in series and you now have no protection against voltage spikes. Sudden changes in your design now have an extreme effect on these high output special effects lights.
This is not saying that such lamps in any way blow at a heart beat or are not industry tested, only to say that they are not any form of other than special effects lighting lamps.
Such lamps and fixtures are not good to be using for other than effects lighting. After that should you want ACL bars or in series fixtures, Kupo, TMB, probably Thomas and Penn amongst others probably all make still the PAR 36 long and short fixture. Looks like a rock and roll PAR 64 but smaller. You can probably also find them in the various resale markets for used lights. #4596 fixture ACL’s are not used much these days. Just sent out the first two shows in years using them.
Between relying upon a pinspot and a ACL in PAR 36 size, neither are very efficient. Much better stuff out there. My recommendation would be to keep looking or refine what specifically you are looking to achieve by way of effect or general lighting and ask about it. Yep the ACL’s are going to be brighter, nope you would not want to be re-lamping or depending upon them.
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Topic: ACLs vs Pin Spots (Read 9057 times)