I've got that exact unit on 3 x 50W bulbs. They do not fail any quicker than the ones on single toroids, in fact, I'd say, they last longer. Probably due to its output regulation being better than the mains itself. And it having a slow start built in.
Using my favourite Newey and Eyre bulbs, I've replaced just two bulbs in
8 years now. And its always in use. Over the cooker.
Mine is actually inaccessibly buried in a stud wall. Never gone wrong. If it does I will have to pull some plasterboard off to get at it. Its a cool running thing. plasterboard gets faintly warm that's all.
Torrodials have the space to [ut multi ouput term strips and you run lamps radially , each has a line.
4* 50=3D 200W
200/12=3D 16.7A
Cable from trafo needs to be rated to carry that full length almost of cable and go in and out of connectors at lamps.
Or put in additional JB and loop out radials.
Trafo per light really is easier at same or less cost, try and get the trafos with mains loop in /out , thought TLC did them but not apperntly, pay no more than a fiver per trafo unless its Mode or IBL.
Indeed - for a 50W lamp its probably something like 0.2 ohms (compared to getting on for three ohms when hot), however compared to the 0.009 ohms of a couple of meters of 4mm^2 cable, that's still means the cable makes up under 5% of the total circuit resistance when cold.
So within even the (more stringent) 3% allowable for lighting under the
17th edition...
From my observations, with say 3 or four 50W lamps on a 250W SMPSU, radial wiring, 1mm^2 cable, there is no perceptible difference in start times between lamps at 0.75m and lamps at approaching 3m. The difference between a slow start transformer and one that is not however is quite perceptible.
Hence why I wonder if there is more going on with your lamps than just cable resistance.
Well yes, but I don't see why the comment about an "odd wattage indeed" is about.
Surely all that matters is that max output of transformer divided by number of fittings, comes out at a number greater than the max wattage of bulb available?
A mate of mine had a crappy ikea light fitting with a iron xformer in the base feeding a couple of 50W spots on stalks. It failed, so I said get the smallest 100W transformer you can, and I will replace it. Needless to say, the SMPSU style one he brought back was an inch too long to fit the case. He was about to take it back to the electrical shop, when I suggested a bit of lateral thinking - rather than attempting to fit it back in the base of the fitting, just post it into the hole in the ceiling above the fitting!
Those transformers typically have six output terminals (i.e. 3 on each leg) on the LV end - which makes radial wiring directly from them quite easy. (although conversely, they are not well suited to backbone style wiring since the individual terminals will not take 6mm^2 cable.
Er: unless this is some huge works or restaurant kitchen: if you are contemplating 800W of lighting, just in the ceiling, you ought to be rethinking fast: you could practically cook on a 50W halogen, and I'm surprised that anyone can bear how bright and hot they are (not to mention the heat in the ceiling space).
Our kitchen - admittedly only ~10'square - has 6x20W halogen in the ceiling, and 5x10W T4 strip under the cupboard units, with an occasional (very bright) 20W T4 fitted into the sash window architrave. Not my design (apart from the window light extra) so no boasting intended, but it's about the best lit kitchen I've worked in. With 800W in the ceiling, in a typical kitchen, with it's work surfaces round the sides, you are just going to be cooking your back, whilst what you are working on is obscured by shadows. And you are also burning cash in the form of energy you do not need in the least.
I think you've misunderstood, I'm planning to install 8x50W =3D 400W. If it's brighter than necessary I'll switch to 35W bulbs.
I did say that I already have very good task lighting under the wall cupboards.
We don't spend a lot of time in the kitchen so I'm not too concerned about the power consumption, though I am planning to refit the whole house with LEDs one day when they become a satisfactory alternative.
I think you've misunderstood, I'm planning to install 8x50W = 400W. If it's brighter than necessary I'll switch to 35W bulbs.
Oops:-) does look like I went a bit cross-eyed there. But do try before fitting all 50W: I did plug one in once - think I still have spots before my eyes!
I did say that I already have very good task lighting under the wall cupboards.
We don't spend a lot of time in the kitchen so I'm not too concerned about the power consumption, though I am planning to refit the whole house with LEDs one day when they become a satisfactory alternative.
Glad to hear it. I do find myself feeling a bit guilty about the halogen lights. Think we used to get somehow lulled into unconsciously equating low voltage with low energy, but they do somehow look more satisfying than the tubes would in a similar position. Another time, probably better to go for a translucent suspended ceiling rather than the plastered one we have. Mind you, even with LEDs the trend seems to be packing more of them together...
Did you think that lighting was a low energy activity, human eye can work down to low light levels which isn`t same as being comfortable with them.
Anyone want to buy some low energy heating......
Use your halogens in good conscience , most of the bad press comes from using wrong type in wrong place, spotlites for area lighting.
Much more efficient, as they try and persuade people useless GU10s are worth using then the ,ahem, energy saving cfl retrofits.
Best LED fittings have about a 20% advantage over halogen at moment, thats for an outlay of several 000% more in lamps and drivers.If your a commercial establishment running lamps for extended periods and cost of a lamp outage can be high, its worth it.
Best light quality on market as halogens inventor calls it, fluoro can actually be pretty good but rarely in CFL form .
Spend the cash on draught proofing and insulation , chasing lighting trends isn`t going to save you money.
Electronic transformers have better regulation due to lower winding resistance, but they still aren't fully regulated (there's no feedback from the secondary voltage to the primary oscilator, and the design bares only a very limited similarity to a proper switched mode PSU - they are really just a high frequency transformer). However, they do have a minimum load cutout, unlike a wound iron transformer, to protect against significantly out of regulation voltage due to low load.
I have recently replaced 60W mains candles and golf balls in a room with 35W 12V capsule lamps in same fittings. The result is noticably brighter. Unfortunately, I didn't measure the light level before removing the mains bulbs so I can't give you a quantitive improvement, except to say it's noticably brighter.
Did you think that lighting was a low energy activity, human eye can work down to low light levels which isn`t same as being comfortable with them.
Anyone want to buy some low energy heating......
Use your halogens in good conscience , most of the bad press comes from using wrong type in wrong place, spotlites for area lighting.
Much more efficient, as they try and persuade people useless GU10s are worth using then the ,ahem, energy saving cfl retrofits.
Best LED fittings have about a 20% advantage over halogen at moment, thats for an outlay of several 000% more in lamps and drivers.If your a commercial establishment running lamps for extended periods and cost of a lamp outage can be high, its worth it.
Best light quality on market as halogens inventor calls it, fluoro can actually be pretty good but rarely in CFL form .
Spend the cash on draught proofing and insulation , chasing lighting trends isn`t going to save you money.
Cheers Adam
All water off a duck's back to me Adam. I don't need any research: it is plain before my eyes that I get much more usable light out of a T4 tube than from a halogen of the same wattage. All the halogens have going for them is a sparkly look: which I do like, but it is still a relative waste of energy. On the other hand LEDs seem to be dazzlingly bright and hard on the eyes at the same time, but not to actually light up anything very well at all: so T4s it is (albeit the ballast does not last very long,,, can't win ;-)
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