Electronic ballast for fluorescent lamps

[SBS]

Hi,
I am looking for an electronic ballast which
could drive 8W fluorescent lamp(s) (UVA tube).

I found some electrical schemes on the web, but
I wasn't be able to find the suitable transformer.

Can someone tell me about a good ballast design,
please?

Thank you and regards.

 

[martin griffith]

Hi,
I am looking for an electronic ballast which
could drive 8W fluorescent lamp(s) (UVA tube).

I found some electrical schemes on the web, but
I wasn't be able to find the suitable transformer.

Can someone tell me about a good ballast design,
please?

Thank you and regards.

You will probably have to have the transformer custom wound, which is
normally no big deal

Loads of stuff here
http://www.irf.com/product-info/lighting/


martin

 

[petrus bitbyter]

Hi,
I am looking for an electronic ballast which
could drive 8W fluorescent lamp(s) (UVA tube).

I found some electrical schemes on the web, but
I wasn't be able to find the suitable transformer.

Can someone tell me about a good ballast design,
please?

Thank you and regards.

You can drive an 8W fluorescent lamp with a simple circuit that requires no
coil or transformer.
http://www.repairfaq.org/sam/linefl.gif

petrus bitbyter

 

[SBS]

petrus bitbyter ([email protected]) ha scritto:

::: I am looking for an electronic ballast which
::: could drive 8W fluorescent lamp(s) (UVA tube).

:: You can drive an 8W fluorescent lamp with a simple
:: circuit that requires no coil or transformer.
:: http://www.repairfaq.org/sam/linefl.gif

Thank you veru much. Is it safe for my fluorescent tubes?

Regards.

 

[petrus bitbyter]

petrus bitbyter ([email protected]) ha scritto:

::: I am looking for an electronic ballast which
::: could drive 8W fluorescent lamp(s) (UVA tube).

:: You can drive an 8W fluorescent lamp with a simple
:: circuit that requires no coil or transformer.
:: http://www.repairfaq.org/sam/linefl.gif

Thank you veru much. Is it safe for my fluorescent tubes?

Regards.

Guess so. I build one and it works fine. A friend of mine has an inpection
light with similar circuit. Worked fine as well untill it fell too hard one
time. (This broke the tube and the enclosure, not the electronics. I checked
it out by myself.) Some say the lifetime of the tube will decrease. Maybe
true, but I've had no problems so far. The only drawback is some more
flicker compared to a conventional ballast, so it may not be a succes as a
reading lamp. I also experimented with the electronics of a worn out
electricity-saving lamp. A 8W tube works really fine on the electronics of
such a 9W lamp. If you google around, you will also find some sites dealing
with this things.

petrus bitbyter

 

[RHRRC]

You can drive an 8W fluorescent lamp with a simple circuit that requires no
coil or transformer.http://www.repairfaq.org/sam/linefl.gif

This circuit looks like a typical 'play around with lots of components
but ensure you do not know anything about what you are doing' type
circuit.
On 220V ac a single series cap will work as a ballast. Since many (but
not all) 8W T5 tubes's, at room temp, will begin to arc as low as 250V
- that is all that is needed.

From memory the arc is run at around 50V for a T5 8 watt.

With a capacitive ballast the crest factor is appalling, the cathodes
will be stripped etc, life and output reduced. That is why it is not
used.

Why do you need an 'electronic' ballast?
What is the advantage of an electronic ballast in your application -
size, thermals,..... ??

 

[SBS]

RHRRC ([email protected]) ha scritto:

:: Why do you need an 'electronic' ballast?
:: What is the advantage of an electronic ballast in your
:: application - size, thermals,..... ??

I need an electronic ballast because I want to reduce
size and weight of the resulting device I am building.

Petrus suggested me to use the electronics of an energy
saving lamp with about same power consumption of
the fluorescent tube I have to use. Other experience
with electronic ballast from energy saving lamp?

 

[petrus bitbyter]

This circuit looks like a typical 'play around with lots of components
but ensure you do not know anything about what you are doing' type
circuit.
On 220V ac a single series cap will work as a ballast. Since many (but
not all) 8W T5 tubes's, at room temp, will begin to arc as low as 250V
- that is all that is needed.
With a capacitive ballast the crest factor is appalling, the cathodes
will be stripped etc, life and output reduced. That is why it is not
used.

Why do you need an 'electronic' ballast?
What is the advantage of an electronic ballast in your application -
size, thermals,..... ??

Well, I neither designed nor analysed the circuit but if you want to...

A lot of circuits of commercial available electricity-saving lamps can be
found on:
http://pavouk.comp.cz/index.html
That guy Pavouk dissected a lot of them.

Another experiment:
http://tacashi.tripod.com/elctrncs/inverter/inverter.htm

I myself use the electronics of a 20W electricity-saving lamp to drive a
circline 22W tube. Even works with some older tubes that did not start on
the original - classic - ballast anymore. (Which was the main reason to drop
the old ballast. Tubes became useless much too fast.)

You can buy an electronic ballast as well. Conrad for example sells them:
http://www1.conrad.de/ (German)
Look for partnr. 571449 - 89

petrus bitbyter

 

[Ian Malcolm]

Guess so. I build one and it works fine. A friend of mine has an inpection
light with similar circuit. Worked fine as well untill it fell too hard one
time. (This broke the tube and the enclosure, not the electronics. I checked
it out by myself.) Some say the lifetime of the tube will decrease. Maybe
true, but I've had no problems so far. The only drawback is some more
flicker compared to a conventional ballast, so it may not be a succes as a
reading lamp. I also experimented with the electronics of a worn out
electricity-saving lamp. A 8W tube works really fine on the electronics of
such a 9W lamp. If you google around, you will also find some sites dealing
with this things.

petrus bitbyter

Been running a normal 8W tube off a ballast from a 9W lamp on our boat
for the last year. Must have close to 500 hours running time now with no
problems whatsoever. Its far cheaper than you can build it, even buying
a decent quality energy saving lamp new.

 

[Paul Hovnanian P.E.]

Hi,
I am looking for an electronic ballast which
could drive 8W fluorescent lamp(s) (UVA tube).

I found some electrical schemes on the web, but
I wasn't be able to find the suitable transformer.

Can someone tell me about a good ballast design,
please?

Thank you and regards.

Maybe the folks on sci.engr.lighting have some ideas.

You might want to provide some additional info. like lamp part number,
supply voltage, etc.

 

[Victor Roberts]

Maybe the folks on sci.engr.lighting have some ideas.

You might want to provide some additional info. like lamp part number,
supply voltage, etc.

As Paul has stated, all 8-watt fluorescent lamps do not have
the same electrical characteristics. I suspect you have an
8-watt T5 lamp, which has a diameter of 5/8 inch and a
length (end of pin to end of pin) of about 12 inches, but
you may have another lamp with different electrical
characteristics.

Your inability to "find" a suitable transformer is not
unusual. Most ballasts I am aware of use custom
transformers. The reason for this is that electronic
ballasts do not operate at a standard frequency and they run
a great variety of lamp loads. So, usually a standard
ferrite core is used, but the number of windings and the
number of turns on each winding, are customized for each
application.

There are also many designs that use only a series inductor,
which is easier to design and build than a transformer.

You can find designs that use standard magnetics at
http://www.irf.com/technical-info/refdesigns/lightingkits.html,
but I don't see any for any 8-watt lamps (but then again, I
didn't look very hard.)

--
Vic Roberts
http://www.RobertsResearchInc.com
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