Hello all.

I've recently come across a fixture for single 13W T5 tube with integrated electronic ballast, but sadly it is not working and I haven't managed to fix it. Now, in order to have some fun with it, I came to an idea of improvising an incandescent ballast for it. From what I've read, 13W T5s have ignition voltages of 230+ Volts (meaning they should start reliably on EU mains), and running parameters of 95V 0.165A. Does it mean that all I need to run the tube is an incandescent bulb of about 130V and 0.165A in series with the tube, and the tube would strike spontaneously (with no additional gear needed) as soon as everything is connected to mains voltage?

Thanks in advance.

Hello all.

I've recently come across a fixture for single 13W T5 tube with integrated electronic ballast, but sadly it is not working and I haven't managed to fix it. Now, in order to have some fun with it, I came to an idea of improvising an incandescent ballast for it. From what I've read, 13W T5s have ignition voltages of 230+ Volts (meaning they should start reliably on EU mains), and running parameters of 95V 0.165A. Does it mean that all I need to run the tube is an incandescent bulb of about 130V and 0.165A in series with the tube, and the tube would strike spontaneously (with no additional gear needed) as soon as everything is connected to mains voltage?

Thanks in advance.

It should work, As that's how self ballasted Mercury Vapor bulbs work. A problem is you may need a 150 Volt bulb, Because it will be dropping 150 volts(At 240 volt AC),And incandescent bulbs don't like having a higher voltage.

U will need a 40 watt GLS 240 volt  to run this 13 watt T5  as a ballast also u need to use a starter as well with this lamp.

U will need a 40 watt GLS 240 volt  to run this 13 watt T5  as a ballast also u need to use a starter as well with this lamp.

Unless you have some kind of instant start concoction.

Thanks wattMaster and funkybulb

Finding appropriate bulb is not an issue - I plan to use Christmas lamps in series, and I can "fine-tune" the voltage and current of my "ballast" by selecting bulb count. If everything turns out as planned, the bulbs will be invisible in the base - pushed where the original ballast was.

Do I need the starter? So, the stated 230V "ignition" voltage implies preheated tube?

Why would he need a starter? Surely if there's no choke them there is nothing to give the starting voltage kick. Or is it simply to preheat the cathodes

The ignition voltage is higher than 230V. The starter can't make HV pulses from a resistive ballast, but only from an inductive ballast. Thats why UVA fluorescent lamps inside a cylindrical bug-zappers, that uses a resistive ballast, uses some form of voltage doubler to instant start the lamp with cold cathodes (And the lamp ends blackens fast as a result).

The starter shorts and heats the electrodes, making electron emission cloud around them - Better than applying 240V to cold metal and waiting for something to happen

Or use 10/13W PL-C ballast with this lamp

You may try the starter, but with the zero crossing reignition spikes associated with a resistive ballast there is high risk the starter will continue flashing even when the lamp ignite well, so you may need to use really a manual preheat. With that it should work reliably.
Of course, being 130V lamp, I assume you are living in a 230V (or so) area, it won't work on 120V.

And a note: Never ever use any electronic starters with other than inductive ballast, it will get killed (the GTO used there is extremely sensitive to dI/dt, it really counts on the inductor to limit the current slope to a safe value)

Thanks all

I will first try without the starter to see if the tube can be ionized by mains voltage peaks alone. I remember my new 20W T12 tubes starting instantly on a magnetic ballast, the starter used was 65W. Perhaps the right one to try on this tube (if needed eventually) is exactly the 65W type again, because of it's higher "activation" voltage.

The first bulb string I tested had current of 0.125 A. I'll need to make sure they can survive 0.165 A, although they didn't seem white hot at "standard" current.

Thanks for the tip regarding electronic starters, Medved. I have only one, as they are rare in my country. I remember using it as a kid in series with the incandescent lamp (I made simple "flashers" using bimetallic starters in series with the bulb), and it survived - all it did was to make the bulb glow for a second or two once it received power.