Parcans

Inaki2

Active Member
We did some research to buy some more parcans at the company I'm working for, and one of the companies we called said the new standard is hat Parcans shouldn't have an open back (were you rotate the lens). Is this so? Is anyone aware of this regulation?
 
Yep, This is very true...

Parcans now must have the "Hat" or little part with the screw nob sticking off the back for saftey reasons.
A number of people have been shocked, if not killed by the old style parcans.
The reason for this, was because the old style parcans have an "open" back on them, so to rotate the lamp which you sometimes do in focussing, if you have ever noticed parcans have a strip of lighting throw as oppose to a circle, this is noticble when used from greater heights.
So by sticking your hand in the back of the parcan, and rotating the lamp you were touching live wires going into the top of the lamp which i think its called the ballast. So for this reason, they created the little cap, which enables you to turn the lamp without sticking your hand inside the parcan.
 
Ballast, no, that's something that ignights and maintins a arch lamp but as for the rest, very interesting. Very interesting indeed - I learned something new today. Way back when I was a fan of some Colortran aluminum Par fixture where the cap for the instrument swiveled in the top hat par of the instrument. Could with the swivel handle even use the rear end of the light for a big flash light without the yoke and top hat part. Loved them lights.

Once had some more or less home made par cans at work with sealed backs but no handles. What a pain in the rear. So the next generation of Par can has focus knobs. Wonder how it works? I agree it's much safer given the amount of heat wire feeding the lamp base that seems to melt or become unbraided. Adjusting focus on PAR cans was always something I did consider as taking one's life in one's hands. Thanks for the info!
 
i knew i remember ballast from somewhere, just not sure where... now it all fits to the time and place haha....
ALL parcans in australia have the little cap now, we have very strict industry regulations that made people either buy caps or replace their cans.
So just about everywhere you go now has nice new par cans.

Our power here is 240v parcans, but we used to be able to buy 110v ones and use a "splitter" so chop the ends off the 2 parcans cables and put one plug on the end, or make a device with 2 plugs that you plugged the cans into with one plug, like a y-lead but for power.
These used to be exspecially handy, as they were the same price to hire as normal cans, and the same wattage, so you got twice the light for the same price, but then the Australian Standards decide that it was highly unsafe to do this and rah rah rah, this was at the same time they banned the use of double adaptors and powerboards in industrial and commercial applications. to use a power board in a theatre or factory, it has to have its own breakers and whatever else..... they got carried away :(
 
We still use the 110V parcans with a series. And yup, I got shocked quite a bit with Parcans....
 
Just got in 114 ProCan Silver parcans. None have a cap covering the lamp housing. Same basic can as always except this time we bought them without the power cords and lamp bases. That was my job to do it in our own way instead of using the normal crappy power cord that comes with them.

It would seem that the cover for the PAR 64 you cite is either a national or local rule for PAR cans as these new fixtures by TMB - probably the #2 supplier of them in the US after Tomcat certainly in the US will have complied with the policy, much less I will have heard about it before now. So in the end, while the cap/focus handle on a PAR can is a good idea, it is not an industry standard.

A shame, but than of course before a few weeks ago, when Kid Rock was installed on the WisiWig, the stock PAR can was a dinosour of the industry. Now that we sold off a few hundred of the old cans, "theyre back!" New cans to replace the ones we sold off just like the AF-1000's we sold off right before another tour, now what to do with the new ones we had to buy once they are also not of use anymore.

Anyway, 60 of the new par cans are using the new to the industry 800w Ray Light lamp in it's reflector fitting instead of the normal PAR lamp. That's at least a useful role for a par can besides a silver ETC S-4 par when painted silver would be a pain in the rear to do.

That and I can honestly say that even if I'm not on the tour - thank goodness that other people do that kind of thing, I did wire up all of it's `30 or 140 par cans. In my book that qualifies me to wear this year's tour shirt.

Final note, I overheard we are not hiring at the moment, anyone interested submit but don't expect work for now. - sorry to those I said we are always hiring.
 
Ship, what do you use for wiring the Parcans? I'm specially trying to solve the wire from melting and/or cracking inside the housing.
 
Wiring a par can:
Factory parcans usually come with a medium temperature cheap euro thermoplastic cable that is wired to a porcelain terminal block. From there the lamp base at best 200c wire leads are wired into the terminal block. All are frequently done without ferrules properly sized to the wire if any. For strain relief, they use something like a PG-29 or PG-11 plastic/rubber strain relief from memory. The ground wire is either riveted to the lamp cap or screwed to it with a nut and lock washer.

The problems with this is that the cable used to feed the instrument is too light duty and low in temperature resistance to withstand constant use, much less it’s not oil resistant (smoke fluid) and in general does not last long especially with heat before it becomes unsafe to use. The lamp bases in general don’t hold tension as well - the metals used to retain the lamp are made with lesser grades of metal it would seem so as with testing over time it will be noted that you cannot pick up a lamp by the lamp base which would be the proper tension. That plus since it’s only a porcelain lamp base with out any aluminum frame around it reinforcing it, it breaks easily.

The heat wire coming off the lamp base itself given cooling out the rear of the light is usually sufficient up to the terminal block that connects it to the cord. That block frequently comes loose or cracks thus posing it’s own problems between loose set screws, rusted set screws, and it in general freeing itself from the side of the par can than breaking. When wire even tinned wire is clamped down on by a set screw it all too frequently is stressed where the set screw is clamping on the wire but lacks sufficient tension where ever the wire is not directly clamped down on by the set screw. This causes strands of wire to break, arc between strands and in general overheat when current is forced to jump between strands. On the lesser temperature rated cord part of the terminal, this arcing is even worse especially if not in a ferrule to band the wire together. The cord’s conductors can’t withstand the heat as well in that distance between strain relief and terminal block and all too frequently is heated to the point the insulation reaches past it’s operating temperature and is brittle or cracking. This is all most evident on the ground wire that directly attaches to the metal of the frame. It’s insulation frequently either melts away or flakes off exposing the conductors to direct heat and oxidizing them which makes them a more resistant ground. That and the screw or rivet becomes loose with use and adds to that lack of low resistance path for a short to travel.

The strain relief also in being plastic/nylon at best can’t withstand the temperatures the par can will operate at and it’s nut becomes brittle. Heyco strain reliefs of this type while an industry standard do not take heat that well nor hold it’s tension onto the fixture well with movement or twisting in the cord. In other words, even if that nut does not break or crack, it still comes loose and because it is not glued together, there is nothing to help prevent this. The rubber tensioning part of the strain relief also does not hold up well to heat, it becomes brittle with age and heat which in time prevents it from cushing the wire against flex. The teeth that compress the rubber ring part of the strain relief far too easily both over tension the wire in just making a cheap wire tight enough and dig into that same wire when the rubber breaks down or is pushed out of the way.

The cord itself as it comes out of the strain relief is too cheap in quality to resist tight bending right at the strain relief. In a way kind of like rubbing a rope up against the sharp edge of a rock that cord breaks down both with heat from the can and sharp edges bearing down on it, plus a ease in ability to flex all too close to the strain relief. That cord breaks down at the strain relief. Hopefully that PAR can’s cord does not touch the fixture because with a 1Kw much less available 1.2Kw load, that cord’s temperature rating would receive a serious challenge to it’s heat resistance.

When you install the cord onto a stage pin plug, hopefully you are using ferrules. Unfortunately they are not doing much help. 16 to 18AWG wire going into a 12 AWG ferrule means that while the set screw of the plug is not directly cutting into the strands of the wire, it is flattening it out causing electrical resistance as the current travels from a flattened section of wire to it’s circumference. That’s given all the strands are intact even. Than there is the same problems as the strain relief has with a weak easy to bend cord clamped down on by a strain relief, but in this case that plug is a dead weight the cord is supporting instead of is supported by. While there is hopefully not heat involved with the area of flex, the weight plus the folding that goes on also serves to break down the cord.

That’s problems I have found with stock par cans no matter the brand.
 
The solutions for these problems are varied.
First with the strain relief, every time that you change a lamp base, you should look at the rubber ring to see if it’s still in serviceable condition. Replacing the strain relief with a better one such as a weathertight one that also uses a rubber ring to compress down on the cable - but a larger one so as not to wear out as fast is an option as is using a two screw strain relief with some nylon tubing between wire and clamp. But it’s a par can and in general not worth that much in parts. Instead adding some weatherstrip adhesive to the threads on the nut will prevent it from coming loose necessitating retightening it. The less you touch such nylon nuts, the less chance even if heat breaks them down that they will fail with abuse. The rubber ring needs to be under the jaws of the strain relief or they will dig directly into the wire and cut it. If that ring starts to get little cracks in it or does not extend under them any longer it’s time at least to replace it. The next improvement to the strain relief will be in preventing the wire from flexing right as it exits the strain relief. High temperature fiberglass electrical tape is rated for it and higher temperatures yet. It will withstand rubbing friction upon it as the cable moves about and prevent the wire from flexing too close to the strain relief if it extends past the strain relief by at least ½". It will also prevent the little jaws of the strain relief from digging into the wire. Fiberglass tape at least two wrappings of it will prevent the cable from breaking down after it exits the strain relief and prevent any heat from transferring between the wire and it’s strain relief. The only trick to remember is to end that wrapping of the tape under the strain relief or it will come loose.

PAR Cans for our use pose a problem for us. We use them both for old style ray lights and normal GX-16d or EMEP (Extended Mogul End Post) lamp bases as used on a PAR 64 lamp. The old style ray lights were not yet designed to slip into the EMEP lamp base and necessitated female to male quick disconnect terminals to attach between them and a cord that’s also used for a EMEP lamp base or to swap out broken lamp bases. Our EMEP lamp bases were cut short on the wires feeding them than fitted with similar receptacles to make them universal with ray light lamps or even a ACL (aircraft landing light) lamp using screw terminals. In other words, due to a frequently breaking lamp base that is normal to other than Osram aluminum frame protected lamp bases, the porcelain only lamp bases of the past frequently broke and needed replacement. Since all cans had one of three types of lamp it, they needed to be used with the quick disconnect terminal in the only solution for them as a junction between the cord and what ever type of lamp fitting it was to use.

So over the years, the company I work for came up with a nylon female 0.25" quick disconnect terminal terminating the ends of the hot, neutral and ground wires off a cord. The ground I’ll explain later. Nylon while rated for the same temperature rating as vinyl and PVC at least does not melt as easily when it gets hot. It becomes brittle which is not good but at least no conductors are instantly exposed. I’m not a fan of the system but it has been in use many years. The male disconnects are from AMP and have large covers over the terminal allowing the nylon to cool on both sides of the splice thus to some extent keeping them a touch cooler than normal crimp style insulated terminals. Crew chiefs like such a system because 30 feet up on a truss, they can lean over and with one hand replace a broken lamp base with a similar set up one. You do not have to attempt to remove an entire lamp cap or fish wires thru the strain relief. The Leko prep people like the system because all lamp caps are universal between the three lamp types used.

They attached #8 stud to quick disconnect tabs to the screw terminals of the low voltage lighting ACL lamps which would adapt from a screw terminal to a crimp type quick disconnect female. On the lamp base, they used Amp brand heavy duty male disconnects and covers to go into the female insulated terminal on the feeder wires. And on ray lights, they used the same system. Simple and easy no matter what lamp is used in a can. Also since there were terminals on the wires, the cords were easy to remove in fitting the cap for a series wired ACL bar or replacing the cord.

Problem is that nylon only has a operating temperature of 180 degrees F. Should any insulated parts of the disconnect touch the lamp, much less with time and heat, it cracks and becomes brittle if not melts. Not something you want inside a can and they constantly needed replacement. Than there was those that did not realize that the amp quick disconnect required a special crimping tool and that unless you used the proper Klien/Stakon crimp tool for even the normal female crimp it would come loose. In other words, in addition to the terminals breaking down, they frequently came loose from improper installation. The system was universal for various lamps but a maintenance hassle. In switching over to the new system it was important to convince those that would nay say that the two major hustles in being broken lamp bases was fixed by a new style of them, and that the second most common problem - the splice was what was being replaced. Given both you no longer had to replace the lamp base. This is an on-going retraining program for the tech people that are used to quick disconnects inside a can. Decent idea, but not rated for the temperature any better than the stock par can parts.

We stopped buying replacement VDE grade fixture wire for par cans. Sure it was a direct replacement and frequently even better than what came with the cans, but still not something that would last. Better types of 200c heat cord such as Suprenat Heatzone wire are on the market and are far superior to the Euro crap that comes with par cans, but they are cost prohibitive for a bulk low tech fixture. Instead, since a lamp base can be bought with a 40" whip, why not just use the heat wire leads coming directly off the lamp base? Given new style ray lights that have similar lamp bases to that of a PAR can, just using improved lamp bases less easy to break and with the long leads would be the solution. A ACL lamp since it’s low voltage needs to be wired in series. Given that, and the less heat it’s going to be operating under - not used as much amongst other things, than such lamp caps should be wired directly to the lamp bar anyway and not need to be mixed in with normal cans that can go lamp bar or independent. Given enough lamp caps to do both, that’s the solution. That’s given new ray light kits. If no new ray lights, than extra care needs to be taken with a quick disconnect and they should be kept to a minimum amounts in stock with nylon crimp terminals. That’s my solution until the ray lights wear out. There abouts of 2/3 of them are already on the way to the trash due to melted wires out of the lamp base. The replacements will fit in cans without quick disconnects. Unfortunately, there is still about 100 more PAR 64 ray lights to go before they can be replaced.

That’s the solution I’m changing to at the moment. For lamp bases, I still have some old style non- aluminum frame types in stock and of them they all get a tension test. Any lamp base that does not have sufficient retaining pressure to pick up a lamp by the lamp base is tossed into the trash. Too much chance that lamp base would come use in transport causing problems at a gig. Any with broken parts get replaced to a point. The quick disconnect is also tested for tension.
The rest are all aluminum frame type lamp bases that are protected from abuse and in general seem to last longer. Those are perminatly wired to the cord. Some of the stock retains a quick disconnect terminal between lamp base and cord for use with either ray lights or old style par cans, but in this case at least now I’m using a non-flammable nylon female insulated terminal. It’s not rated for any higher temperature but hopefully will not become brittle as easily. The male terminals are the same given tech people working on them know about the proper AMP crimp tool, but all wires feeding male or female terminals because the fiberglass braiding has problems with unbridling, have been fitted with high temperature heat shrink to prevent the fiberglass from coming loose and becoming unbridled at the disconnect. This means there is no chance the insulation over the wire will become exposed also. Any wire with fiberglass coming loose or breaking down at the lamp base - especially on old style ray lights, have been either fitted with heat shrink also or been taken out of service. Amazing how the wire on ray lights seems to melt as it comes out of the lamp base but such things are old and better off replaced.

For some reason in something like 20 years of cutting the 40" leads down to about 10" nobody threw out the heat wire from the par cans. I have boxes upon boxes of par can whip heat wire. As I re-wire lamp bars, the ray light - series wired lamp bars get wired with that extra heat wire running between the bar and fixtures. The wires are now terminated in high temperature steel ring terminals so they don’t require any work ever. Lap caps are permanently mounted to the bars and all you have to do is bolt the rest of the can to a bar. Quick disconnects in addition to melting down have this problem of loosening up with use. Do away with them and you have a more dependable fixture.

As said, some of the more normal PAR fixtures are kept in old style so as to be used either with old style ray lights or can fixtures. No more than say 100 of them as there would not be use for more than say 100 ray lights at any one point. Such fixtures have the old heat wire cords on them terminating inside the can not in a porcelain terminal block but with a improved flame resistant quick disconnect, and it’s fibreglass braiding is held together at it’s stripped end by high temperature heat shrink. Stuff that takes a blow torch to shrink down. For the moment, we are only using normal black fiberglass wire shield over the conductors on the cord. Eventually we will switch to vinyl or silicone coated fiberglass shield as it is showing premiss with other fixtures in being abrasion resistant. For the moment also we are using the Heyco strain relief - I have hundreds upon hundreds of them in stock and can easily replace what breaks down. But the improvement to both is the use of fiberglass electrical tape over the fiberglass insulation to prevent the wire from breaking down where it is clamped down upon and flexing too close to it. This helps a lot.

For the plug end of such fiberglass insulated cord, since it’s 16AWG wire, 16awg ferrules are used with 12ga ferrules over them. This double ferrule both retains the shape and proper clamping pressure on all strands of wire but also brings the wire up to a size that the screws on a slip plug will properly clamp down on. For non-heat wire, stuff that’s 16AWG, it can be folded in half than installed into a 12 AWG ferrule in making it into a 13 AWG piece of wire with a fold to it. This fits well. Any wire when doubled up equals a gauge of wire three sizes larger than it started out to be. Double up a 18ga wire and it equals 15 ga. Since heat wire is tinned it does not fold that well and a dual size of ferrule is best.
At the plug’s strain relief, when I’m doing them, friction tape which is not flame resistant and cannot be used directly on a instrument, but can be used on a plug is used. All tape when put on fiberglass is best off wrapped around the wire some, than the fiberglass slipped over the wrapping, than the tape wrapped over the fiberglass for best use. This forms a layer of tape that prevents the wires from bending too close to the strain relief and with tape above and below the sleeving prevents that sleeve from slipping out of the strain relief. Otherwise, others at the shop use heat wire with fiberglass shielding on a Bates plug with one strain relief fitting flat and one rounded. Works adequately.

The heat wire and fiberglass insulation over it has the advantage of being able to touch the instrument without breaking down. It is not very damage resistant however. To some degree if little abrasions or cuts develop on fiberglass it can have adhesives such as Plyobond smeared on the cut and it will seal it up and prevent it from opening it up further. Otherwise at least like with all other fixtures, fiberglass needs to be replaced with time. No big deal and at least it’s not a question of the cheap semi heat wire lamp cord cracking and exposing conductors with exposure to paint or fog. Switching to the above silicone or vinyl fiberglass shielding will help prevent all problems.

For the ground wire, since fixtures used to be swapped between all three types of use, the ground used to be installed with a stud to quick disconnect terminal. Basically it’s a 1/4" flat section of metal to fit into a female quick disconnect crimp terminal with the other side of it having a hole for a #10 screw that gets mounted on the can. They used to rivet them to the fixture with a 3/16" rivet. Things were never tight enough and always came loose. Than the quick disconnect with use, even if it made it easy to remove the entire whip assembly, started to loosen up in addition to the rivet coming loose. You are much better off with a ring terminal permanently installed on the fixture’s cap. I use Stainless steel 10-32x3/8" hex head screws with stainless steel top lock nuts. The screw uses a 5/16" nut driver, the nut uses a 3/8" nut driver. Very easy to install with the proper tools and the nuts being a top lock type, they won’t come loose. Nylon lock nuts have the nasty habit of melting down or not retaining when in a high temperature environment, top lock nuts use a deformed thread to prevent coming loose. Stainless steel screws while slightly more expensive are a better option for use in fixtures especially at electrical connections for them.

Because it’s the ground and not going to get as directly hot, high temperature ring terminals while they would be nice are not necessary. It’s also not going to matter if they are insulated or not. Should they be insulated types, big deal some insulation melts off the ground. For wire, I use a lower temperature wire. I use silicone FEP / type K 150c heat wire for the ground on a par can. As opposed to type SF-2 fiberglass braided silicone heat wire used for the lamp bases or normal heat wire that’s rated for 200c, in this case I want the ground wire to melt down first should there be a heat problem. Lots of vent holes plus a big opening in the rear of the can. Should not be a heat problem, but if there is, seeing a melted down ground wire would be a good indication - better than other conductors failing. This will give an apparent sign there is a problem in the wire, plus it’s the ground, if nothing else, this can be melted. (Normal building wire such as type THHN or even a rubberized cord such as SJOOW will have a operating temperature of 90c and should be avoided for fixture use. Type VDE is not rated but must be somewhere in the range between 100 and 150c on the outside.) On larger wattage fixtures such as a Mole Light, I use the above SF-2 heat wire for the ground and type TGGT fiberglass insulated Teflon 250c heat wire for the conductors for the same reason. Good stuff, not very flexible but holds up well to heat. When using such TGGT wire, since it’s rated for over the temperature of the high temperature heat shrink, fiberglass or Teflon electrical heat tape is required in it’s place. The FEP ground wire is also much smaller in overall circumference of the insulation which allows for a smaller size in cable bundle when coupled with a few layers of heat tape when going thru the same size of strain relief.

So out of 114 fixtures, I wired up 60 of them plus another 24 with the old system of using a quick disconnect between the lamp base and the cord. The rest used brand new 40" lead lamp bases that were wired directly to the plug. We had a surplus of pre-wired lamp bases and I had to keep a certain percentage of par cans wired in the old style. Otherwise for the remaining stock of par cans, about 50% of the cans now have the new style lamp base directly wired to the cord. Basically it’s quick disconnect terminals were removed and a high temperature butt splice was crimped to the heat wire. Over the high temperature crimp was put high temperature heat shirnk. The stuff sells for like $24.00 per four foot section of it but is well worth it. It’s also supposed to seal up the space between wire and heat shrink against moisture making it more safe yet. Old cords on all fixtures have been removed on all the upgraded fixtures. Crew chiefs complain they can’t hang from a truss above an audience and replace the lamp base with a free hand to which I reply that with the new style lamp base and removing the disconnects that are the parts that fail, you no longer need to replace them. Other cans are being switched to new fiberglass whips and better quality quick disconnects. All ground terminals are directly bolted to the frame using the above method and sealed beam lamps - ACL bars have their lamp caps and wiring perminatly mounted to the bar.

That’s at least what I’m doing with par cans that’s a bit different. Quality after market lamp bases are the key to being able to do this. New ray lights would remove the need for quick disconnects but at least with them still in service they are watched and better installed. Still searching for a high temperature quick disconnect but I have high hopes for the current flame resistant disconnect at least at the moment. At some point I will also stop buying fiberglass shielding sleeving for over the wire use and switch to at least vinyl if not the more expensive silicone. This will make a whip that does not need to be replaced at all.

One final improvement that I did not come up with but approve of is that between the barrel of a C-Clamp and the yoke we install a fiber washer. The fiber washer acts as if a metal washer but in being a cardboard like thing does not allow the fixture to be tensioned enough to the clamp that you still can’t move the fixture on the clamp with one hand. In other words, the fiber washer acts like a ball bearing in allowing you to swivel the fixture by the yoke, yet allows for enough tension on the yoke that it will not move about on it’s own. All our fixtures get these custom cut for us washers. One hand to swivel the fixture is all it takes - a good improvement on fixtures.
 
Wow...Ship, you really took the time to explain, thanks! Loved te fiber washers, now thats a really good idea! We have Parcans with both ceramic bases and terminals, the idea is to change all to ceramic bases, though I still don't like them, they come loose with use cuz the male leads from the Parcans move. So in a gig you find that 2 Parcans wont work (we use them in series) and that gives you one more thing to look out for. For the wiring between the terminal and the lamp we're using siliconated wire that witstands heat much nicer than our average shop wire, which kept melting and cracking.
 

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