Strand lamp bases P28

David Ashton

Well-Known Member
I have been unable to buy these bases, except at extortionate prices, so I have had a batch made, the only difference is white ceramic, not grey, but the question is, did the Strand 23's 123's and223's sell in the US with P28 bases or something different?, I changed some over to GY 9.5 bases but they last nowhere near as long as the old P28's.And have these lamps survived the ravages of time and still in use?
 
...but the question is, did the Strand 23's 123's and 223's sell in the US with P28 bases or something different?...

The Strand Patt.23,
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Patt.123,
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and Patt.223,
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(Photos from Strand Archive-Lantern Index.)

were never sold at all in the US, to my knowledge. Certainly not in any quantity. Similar fixtures by Century, Kliegl, Electro Controls, Altman, Colortran, etc., used the Socket, Medium Prefocus, Bryant, Medium Prefocus Lamp Socket socket, and many still do.
 
Thanks for that information, I tried to order some from both companies but neither will ship to Australia.
 
Tried them, very high prices,[ and thats being diplomatic]
 
Strand did sell these items in Canada, I own and still use 23s, 123s and 223s all fitted with the P28 base.

The strand P28 base uses a diferent mounting hole locations to the regular P28 bases I can buy from Altman and a number of other suppliers. However if it is just the centre terminal it can be removed I found one supplier of P28s where the centre pin can unscrewed and used to replace the centre pin in the Strand item. Alternativley you just need to drill the mounting holes in a new location. I pay approx $15 Canadian including taxes for a P28 base. these are easy to buy over here and the bases are actually made in Japan but I do not know who makes them.
 
I have decided to go ahead with a production run of direct replacement bases, they will be available in about 6 weeks and sell for about $5 US in quantities of 10 or more, it will save me a lot of annoyance and make renovating these lights economically viable, at the moment a base costs nearly as much as the s/h light.
 
Sounds good. I know that they are struggling to find a reasonably priced source for these in the U.K. for the same reasons as you posted. I did have discussions with one U.K. Rental house that was looking for a supplier. If you PM me I can give you the name and contact.
 
I have been unable to buy these bases, except at extortionate prices, so I have had a batch made, the only difference is white ceramic, not grey, but the question is, did the Strand 23's 123's and223's sell in the US with P28 bases or something different?, I changed some over to GY 9.5 bases but they last nowhere near as long as the old P28's.And have these lamps survived the ravages of time and still in use?

Grey ceramic was either GE or Bryant making them, most likely GE but that was like 30 years ago the last of them I have seen. Bryant still makes a black / dark grey lampholder in addition to their white porcelain one but I think it's plastic, GE doesn't make them any longer. Heard before about different mounting screw holes amongst some brands, I would re-drill. Ushio would be another option.

Interesting you have someone able to make them for you so cheap also. I normally just resurface the old lampholder - doesn't take very long and if done well it lasts. I also save my broken lamp bases for use as parts later - Altman center contact unscrews.
 
I'll send you one of the first batch and you can give us an independent critique.
 
I'll send you one of the first batch and you can give us an independent critique.

If reply to me, please do so. Can just give a copy to Darren for his next visit up here in saving money - he normally does a stop over and visit when in the US. Be interested in it and in more info on who can make one and how it is. Given for general use / sales up here it would have to get a UL listing but given the market is shrinking for suppliers of this base type, possible that could pay for itself.

If of help in things I have noted in design on these bases:
mounting screws captured in the porcelain easily break the porcelain when overtensioned or shocked. This is the main problem with the Altman lampholder these days in addition to in having screws retaining the base plate and shell, they can come loose. Current Altman base is also larger in possibly not being the correct seat height for the lamp. It's also a bit tighter in tolerance in fitting onto the fixture lampholder plate if a ground screw is mounted on the reflector bend of it for a Fresnel.

Other brands & older brands, in not having screws retaining the base plate and shell, they can with expansion and contraction loosen up some. The porcelain at the base is a little less substantial (easy to sheer off) and less room inside the bottom for using ring terminals.
Some form of spring retention that compensates for expansion/contraction or resists coming loose would be good. Given the round wire ferrules many of these lampholders were designed for are no longer on the market, and or wrapping a tinned wire around a non-removable screw is no longer viewed as good practice, a slighly larger area inside needs to be provided for use of high temp. ring termianals around the silicone bronze external tooth lock washer supplemented screw termianals. This or I could sware Leviton used to make these bases with a 40" whip pre-crimped to the base so one didn't have to screw with crimping wire to the base. Such a plan of a pre-crimped whip already on the lampholder such as done for many screw type bases would possbly be better. Put some silicone coated or vinyl coated fiberglass sleeving over the fiberglass coated SF-2 wire attached to the whip so as to resist abrasion and flex wear especially where it exits the porcelain.

Other notes, don't matter what insulator between base is used - none hold up well over time to the heat. I normally use a ceramic fiber padding but it don't hold up well to moisture. Might look into a Teflon insulator plate between bottom of lampholder and lampholder mounting plate of the fixture.

Other notes about changes to the lampholder if designing one, Altman has a concave center pin plate which I think better than the older style of doing just a flat plate. Depending on the brand of lamp, some still have a flatter center contact, others have a more rounded bead of center pin. Overall and especialy if that lamp's contact is solder, flat (more or less but more convex than flat) or a ball the cupped base would have suprior contact with any of them I think overall. The Altman base while larger in it's center contact is a design improvement to look at I believe.

If providing mounting hardware, I note some lamp sockets these days are both 6-32 and older I think more 4-40 for US type screws used. 6-32 of at least 18-8 Stainless Steel would probably take heat better and it's easy enough to drill out a fixture for in upgrade. One should instead of the noted captive nuts in the porcelain go back to the old recessed round head screws inside the lampholder to mount them, but on the other hand, one should also provide some form of shock mounting between screw head and porcelain. The shock mounting concept is why I use the Ceramic fiber padding, Teflon isn't as flexible unless perhaps as an under lampholder pad and under screw head type padding in both adding up to some flexibility.

anyway some design concepts if of help. Shells nickel plated, perhaps gold plating on the center contact. Perhaps glazed porcelain in not retaining moisture which could otherwise retain moisture in oxidizing parts, holding heat retaining stains, or stray paint from fixture painting otherwise?
 
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Can you talk me through UL listing, there is a huge amount of information to find a way through?
This unit is a direct equivalent replacement to the grey Strand base, I'm not game to try anything radically different on a first try.
 
UL listing, it's a private company you pay to get a listing for in testing your product for testing it for what you specify them to test it for. Note, there are other companies out there that will also test in a scientific and engineering type of way a product, UL is just the most recognized company for doing so. Listed means not persay code compliant, more that they list a product in having passed their tests for what you paid to send the product into in testing. This stated, UL is very highly respected, and no matter what the above might sound like in pay for play, it's very well respected and doubtful they would cheat even if paying to test the product.

Other privately owned testing companies out there being just as valid (I don't know of any but they are out there I believe), can do the same thing, more just a question of what a local inspector would accept in having been tested (kind of like drape flame testing athorouty acceptance - California being different and if they accept the testing as approved, it for the most part would rate certification.) On the other hand, engineer the heck out of a product, the testing company for all intensive purposes tests for what you pay for. In theoy there is some amount of broad safety type of stuff in them not listing an unsafe product for other reasons than what was specified for them to test for in compliance with norms or the UL/CE but that's not persay a given. One could get a listing on a product that otherwise for a different reason is unsafe.

Dont' know, other than one product where I work getting that compliance - totally seperate department for something they produce for resale by way of a distributer, nothing to do with what I produce which is not done in going for UL listing (at times why I pass on a project if I know there might be a problem there) and more or less in the end as an absolute sense subject in use to any local inspector as per my compliance and the local interpitation of the NEC.

Double ended sword this UL listing in that it don't persay test in paying for what you get it tested for in listing as compling for their tests, but also persay being a safe product, but short of it's listing, also a in general lack of acceptence of it being safe. This much less, just because it is UL listed even, don't mean it will be recognized by the manufacturer of the fixture it would be installed into. Remember a few years ago the C3A socket by Ushio that was was much toughted by members on Stagecraft as a great socket as a replacement socket for the 360Q. Yep, probably was, but in it not being a tested and accepted socket by Altman that recognized in complying for their own UL listing only sockets made by Osram, Bender & Wirth and Buhl, use of such a lamp socket would void the warranty/liabilty of such a fixture. Don't mean a lot years later such as in the fixtures you are replacing bases to but say for a school where they by law cannot do stuff other than code compliant and manufacture spec, such a UL listing, manufacturer acceptance of etc. does matter a lot when it comes down to liability. Use even to date from what I understand by what of what even PA sells for use in the fixture would very specifically void any fixture/manufacturer liability of the equiment manufacturer. That's a very problematic thing but very specific where alternate products come into the concept of "doing the right or better thing" when it comes into conflict with what becomes the legal thing one should be doing.

Still remember a Menorah project I got stuck with a few years ago. Imagine a few like 12' square menorah's rope light lit 3/4" conduit supported symbols in addition to some 10' scaff support bar star of David's lit in a similar way, hanging 80 stories up in the air down town in "the windy city." Couldn't get out of the project up until at 90% done and working a weekend and even shipping it out, I got a "stop" call. Seems the building engineer had a card under his hat I didn't or couldn't find in constantly saying it was a bad idea but do it anyway. He somehow got a $120K engineer's wind tunnel compliance necessity in report thru the management before he would hang the thing - even if half of it was already delivered. "Stop!!!" Way over budget now in if needing such a compliance, it was now way over budget even above doing it in the first place in not persay listening to say wind loading effects - we are talking 80 stories up in the Windy City, and wiring the thing by way of dropping down a power line from like the 100'th story with rigging for it between the top and like 35th' floor. Talking insane here but if required I made it work at least - short of some potential wind / swinging damage to the building and windows on it given suspended symbols. Even safety cabled the conduit so even if it came apart, it wouldn't fall as opposed to the broken glass during a good wind.

In me relating this concept / concepts above, it's an attempt to express the crazyness of any "listed gear" market - the EU has a better system which might in compliance be better to comply with in as an alternate, somewhat better acceptance here. UL Listing a good thing, perhaps as secondary to any EU listing I would go for in necessity. Following both or alternate to UL, than you still have to have the individual fixture manufacturers adopt and recognize your lampholder before for insurance and compliance purposes, they can use them legally. Heck, the HPR lamp got discontinued before Altman recognized it as a lamp as I see it.

Were I you in bringing a product to market, I would first produce it quietly as best in quality I could for sample. Not what I recommend for quality, but what you think best in product. For me in producing the product, it would follow my study into what the products are on the market already and what problems they have by way of improving it in making the next ETC S-4 Leko as it were as a true improvement to what is offered and based on what is offered in problem solving.

I would than if sure of it, get that listing - UL or what ever other similar company. I would than in what mistake Ushio made, present that product to the manufacturers in getting it accepted by them. Will take a long time for both the above. But than in if other than advertised you perhaps wind up you perhaps as the supplier of their latest edition of lampholder, or at least wind up with an accepted lampholder that some junior highschool can use in their fixtures which if a problem the insurance company won't take legal note of in having big or small pockets to sue.

Anyway a concept. Send me a sample, love R&D or play testing, but in an overall sense, even if the UL listing don't really mean anything, it's a coin of the rhelm in getting to an end result in being a good thing that it tests for what you pay for but not persay being a statement of quality.
 
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I forgot that I had this on my site, from a post to the SML by Martin Moore, who was working for Kliegl when I met him in 1980. Patt263history.pdf. Some may find it interesting.
 
An alternative to UL labs is MET Labs, their website is

MET Laboratories, Inc.

The UL listing is also only for the U.S. For Canada you need the c.U.L. listing which is not difficult if you are already doing a U.L. test the two can be done in parallel. However for many components Canada accepts an international test standard such as D.I.N. etc. I would need to look up what the test standards are for a lamp holder
 
I checked up on the UL system,
they make the testing rules,
they do the testing,
before you get your listing you have to agree to having your factory "approved" every year at your expense,{business air fares, 5 star hotels}
It appears to me to be naked protectionism hiding behind a fig leaf of "safety"
Might try an Australian version to test all that US gear.
I'll stick with European, British and Australian Standards which are transparent, you build to the standard and that's it.
 

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