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If anyone wants 954 strip lights they are available here without buying lots
http://www.meteorelectrical.com/ligh...nt-tubes.html#
I've looked for these several times. For some reason my ISP stepped in with a search and came up with these. They also do fitting that seems to be HF
http://www.meteorelectrical.com/1x58...-t8158hf.html#
:( My only problem is that the existing units are longer so guess I'll have to repaint the ceiling.
John
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You could probably retrofit your old fixtures with new tubes and ballasts. I have of course done that umpteen times, as it has been my job, but it is rather simple. I prefer the Osram Intelligent Touch-Dim ballasts, that can be controlled with only a pushbutton. They work with DALI too and are available for all sorts of FL tubes. To get better control over dimming levels, dimming with a resistor, as in Quicktronic De Luxe might be preferred, as you can mark up the levels on your control unit.
Regular 954 tubes have colour drift when dimmed, so dimming them very low should be avoided. There are also special studio FL tubes that can be dimmed lower without colour drift, but I think they are not worth the extra money, as they are extremely expensive. The 954 tubes can be dimmed to about 1/4 output without discernable colour drift.
It isn't difficult to retrofit, but of course you must understand what you are doing and use appropriate gear. All cables must be protected from chafe, and they all have to be changed, as they are connected very differently from the magnetic ballast ones. There is a connection scheme on every ballast, so it is pretty straight-forward.
I've had a very mixed career Urban - electrical and electronic so could cope. The current fittings are rather ancient types that don't use a starter. Also not 6ft long is how I would describe them as they are a few inches under. They are the larger diameter ones too. I feel it's best to start again. The person that owned the house before us was a head mistress so I'd guess who ever fits out schools supplied these as starterless /self starting was only really common say 40 years ago in similar premisses. :) Not sure how old they are but they have certainly been there a long time. We have, for about 28 years now. I'd guess they went up in the 70's. One thing for sure the tubes last a lot longer than bulbs.
My only concern really is if HF might cause the tubes to have problems but as I understand it increases life etc so shouldn't a problem.
John
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If you should use the Quicktronic De Luxe ballast, that is specified to dim with 1-10 V, there is the undocumented feature that it can be dimmed with just a variable resistor, as it has the voltage internally for full power; it supplies full power when no dimming circuit is attached. IIRC, the value for full output is about 1.5 kiloohms, and we used 2.2 kiloohms logarithmic resistors on our dimmable portable units. I will recheck that. The pot thus is connected only by one of the end terminals and the centre one.
You can probably find the same form factor tubes. Perhaps 58 W? The old lampholders mostly can be used when retro-fitting. There are two cables to each end of the tube, and it is well marked on the ballast where to connect them. The feed end is straight-forward too. AC does not depend on which is neutral. The DALI ballasts can be controlled with 230 V at the DALI terminals and a pushbutton. Touch to switch on or off, press to dim. Release to change dim direction.
I've ordered the new bits now. The old tubes are 75/20's but previously I think they had something like 75/85 on them. We have 10ft ceilings so plenty of light is needed. Hopefully the newer 58w T8's will put out similar light levels as I understand they are more efficient.
I'll make a note of the dimmer for if.
John
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