Problems with T24s

[Wuddy]

I have a number of patt 123s and 23s and have always lamped them with T1s being of the opinion, use the lamp they were designed for.

 

Last year, after being influenced by Phillips sales literature about how the T24 was better light output and more robust, I invested in 20 of them.

 

All twenty have failed catastrophically, some within minutes of being powered up, most during focusing in or positioning and some in transit. The complete filament ends up in fragments, not a part of it left in place.

 

I have no problems with any of my other lanterns/lamps (Selecon profiles, Cantatas, Cadenzas, Solos) which get delivered, rigged, struck and re-stocked several times a year, some of the T1s I had in my 123s/23s lasted several years with no failures.

 

Has anyone else had similar problems?

[AndyJones]

Not had any problems with any we use. I guess its a dodgy batch? I would suggest getting in touch with Phillips and explaining the situation. They will more than likley send you some replacements

 

HTH

 

AndyJones

[Neil Hampson]

T24's do seem a bit more delicate than the T1, but in our case the additional light output was always worth the extra risk. The T24's seem to be extremely sensitive to mechanical shock when hot, to the extent that probably 75% of ours blow when adjusting the focus rather than old age.

I remember reading somewhere about the relative life of each different lamp, a T1 is only normally rated for something like 200 hours or so were a T24 is supposed to burn for 800

[Paul Roberts]

Try using T17's instead. I've been using these lamps now for a long time and have never seen them fail until they're really worn out. At my old school, there were some T24's in stock but they seemed very sensitive while focusing, as other posts have already mentioned.

[Grahame]

All twenty have failed catastrophically, some within minutes of being powered up, most during focusing in or positioning and some in transit. The complete filament ends up in fragments, not a part of it left in place.

This is not intended to sound like I'm being totally patronising, but it's a question that needs to be asked - did you use a protective covering to prevent fingers touching the 'glass' of the lamp when installing them?

If not, then that's probably the reason they didn't last long. T1's have conventional glass envelopes; T24's are quartz glass, which doesn't deal well with sticky fingers.

 

Again, sorry if this sounds patronising, but it's an easy mistake to make if you're not used to quartz halogen lamps.

[Neil Hampson]

Try using T17's instead. -Snip

 

I thought the T17 was the same as a T24 my supplier lists them as 'T17/24' likewise T26's are often delivered as a T19 I remember a rep telling me that the higher number had a slightly smaller filament area and that the filament was in a single plane, to help with gobo projection - although side by side it's hard to tell any difference

[Paul Roberts]

I thought the T17 was the same as a T24 my supplier lists them as 'T17/24' likewise T26's are often delivered as a T19

 

T17's and T24's are very similar; the filament arrangement in the T17 is different to the T24 though. I'm a bit too busy at the moment to go into the detail of it (and chances are my description would only serve to create confusion) but if you can get hold of each type of bulb and compare them you will see a difference.

 

PS: Having just read the op's message again, I can say that I have seen the T24 blow in much the same fashion.

[David A]

I have been using T17/24 since they came out [about 20 years ago] I have never had a bad batch in all that time and I find they last longer than T18, maybe the base is a better heatsink.Even if you touched them they would not blow quickly as it takes a while for the fault to develop so you can be fairly certain that it is a manufacturing fault or a trauma in transport and the latter would be my guess, I am sure your supplier will replace them and you will have no further problems.2 tips, if possible focus at 80% and if the focus knob jams, turn off, free it up and then focus.