With the ballast bans coming around, i have a suggestion

We need a database of the properties of lamps and magnetic ballasts. This will, with the help of simple LCR meter, pick miscellanous transformers etc available, and quickly find out whether they are by chance a close match for a substitute for some ballast

This will help answer questions like - "can i ue the primary of a 240/24V transformer as a ballast for ... lamp ?", and if anyone can source transformer winding equipment and buy cores online - manufacture any wanted ballast for himself

This database can be made as a category in the gallery, with data as follows (examples, made up the data not real)



Mini N40 ballast

Use : Switch Start 1xF40T12/F36T8/TC-L36 2xF20T12/F18T8
V : 240V
I/work : 430mA
I/stuck starter : 860mA
Inductance : 800mH
Wire resistance : 50ohm
Wire gauge : 26AWG
Core cross section : Appx 500mm^2
Core volume : Appx 45000mm^3

Example use of this data : going through transformers, and picking one where the inductivity is 800mH and wire resistance about 50ohm, and core cross section no less than the original, will probably be a close match for a proper F40 ballast



SON-T 70W lamp

I/correct : 1A
V/striking : 2KV
V/initial discharge : 40V
V/full power, new lamp : 80V
V/full power, aged lamp : 110V
V/full power, cycling lamp : 140V

Example use of this data : calculating an inductance and wire resistance figures to wind an appropriate ballast

also need data info for subitute ballast for 110 volt north american country
such as F40 auto tranformer preheat ballast.

and auto transformer mercury ballast as well

wich is harder to do. i need a junk MV ballast so i can count how many turns and size wire
and core area.

 when I have time i am going to reverse engineer a rapid start ballast. eventhough there pleanty to go around
but it will take about 10 to 15 years to dry up in used ballast market.

You can instead run a choke on 110 to 240 step up transformer, in this case the choke part is no more complex than with 240V - This covers HID autotransformer ballasts and Preheat

For Rapid Start, you can separate the ballast to 3 parts : The step up transformer, choke or capacitor as ballast, and heating transformer. This will be more bulky than the proper ballast but functionally quite close

You dont really need a ballast to destroy. With exposed coil HX ballasts like you have there, You dont need to destroy anything - you can count the amount of turns from wire gauge, wire length (can be measured from wire resistance with ohmmeter, then calculated from the gauge), and how much does fit in the coil. You can, instead of destroying a ballast, wind up a transformer spool of the same size with wire of the same gauge, untill you reach the same volume of coil, that would be moderately close.... Then test it to get more precise result. Or leave several taps from the coil at about the right place. and pick the correct one later by trial and measurement

This would be a great idea, I've been wondering about the possibility of making an SRS ballast!

I found that the old Hornby 12VDC/15VAC model railway transformers are a pretty close match for 1x13W T5 or 2x6W T5 tubes using the primary as the ballast. I believe I shorted out the secondary for this. Pity I no longer have them.


BG