I bought a second hand, mini sun bed to sustain a few bonsai trees, this winter, indoor. The sun bed has a build in transformer to power 6X40W fluorescent lamps, thus a 240W system (220V~50Hz). Unfortunately the UV-lamps do not emit the best spectrum needed for cultivation and growth. The lamps I need to replace the UV-lamps with, has to be 590mm in length, but the highest wattage, available in this length is 20W. I want to know if I am going to blow the 20W lamps if I replace the old 40W lamps. If so, why?
2007-09-21 05:18:59 · 3 answers · asked by matroosje 2 in Science & Mathematics ➔ Engineering
Hmmm, I think it is the ballast; a transformer does not make sense for it is still 220V delivered, right? Those small round things (usually glowing in the beginning to start a lamp) do I have to replace them as well? I am planning to keep 2 of the UV lamps.
2007-09-21 06:24:17 · update #1
Is that built in really a transformer, to provide the proper voltage? Or is it really a ballast, the transformer-like coil that gives the tubes a kick to get their fluorescent arc started at power-up?
The ballast for 40 watts is very different from the ballast for 20 watts. You would need to get enough of those 20 watt ballasts to go with the new lamps. You also need to make sure that the new fluorescent tubes have the proper sockets mounted at the proper distance apart.
One possibility to get going faster and cheaper is to get some new ones in 20 watt but keep a few of the old 40W ones. That way you might get enough total light in your preferred spectrum without sinking a lot of money and time in a complete re-do of the sun bed.
2007-09-21 06:07:34 · answer #1 · answered by Rich Z 7 · 1⤊ 0⤋
It's entirely probable that you will. The circuit will be set up to deliver 40W, i.e. 40 J/s. If this is delivered to a 20 W bulb, then there is twice the energy being delivered to each lamp (without knowing the current/voltage of the system it's hard to say how high the current will be).
This extra energy is highly likely to melt the filament i.e. blow the bulb.
2007-09-21 05:29:25 · answer #2 · answered by Alex B 2 · 0⤊ 1⤋
If the ballast transformer can handle 40w bulbs it can certainly handle 20w bulbs.
You certainly will not blow the lamps.
2007-09-21 06:00:59 · answer #3 · answered by Warren W- a Mormon engineer 6 · 0⤊ 2⤋