Instructables

how to find flyback transformer pinout?

how to find flyback transformer pinout and i don't hav a datasheet
i don't hav anything


AndyGadget4 years ago
I've used the procedure HERE with success.
I have this problem too.

How do I find which pins are the inputs to the primary coil on the flyback?
This site (http://lifters.online.fr/lifters/labhvps/tht.htm) says "With a simple ohmeter this is very simple, you will find easily the primary inputs because the coil resistance is about 1 ohm"

I bought a new flyback a couple of weeks ago. My flyback has 10 pins. I got these results:

Pins ..... Resistance
1 + 5 .... 2 ohms
1 + 9 .... 1.8 ohms
5 + 9 .... 0.9 ohms

2 + 8 .... 0.9 ohms

3 + 4 .... 0.8 ohms
3 + 6 .... 0.8 ohms
4 + 6 .... 0.6 ohms
All the other combinations (i.e; pins 1 + 3) produced no resistance, so that means that pins 1 + 3 are not connected. Conversely, this means that pins 1+5+9 are connected; pins 2+8 are connected; pins 3+4+6 are connected; and pin 7 and pin 10 are not connected to any other pins.

The first problem is that many of these gave me a resistance close to 1 ohm, so I still don't know which pins to use for the primary coil.
The second problem is that a flyback should have two sets of connected pins; pins that connect to the primary coil, and pins the connect to the secondary coil. However, I seem to have 3 sets of connected pins (or five sets, depending on how you count). Does this mean something is disconnected inside my flyback?

I didn't know what to do, so I just went ahead and connected it to the CFL circuit. I tried pins 5+9, 2+8, and 3+4 as the pins to the primary coil, along with every combination of the 4 pins on the CFL circuit, but did not get a single arc for any of them. Does this mean that my brand-new flyback is bad?
The problem is that there are many different designs of flyback transformer.  If you bought it new you should have a part number on it, on the packaging or in the place you bought it from - Do a search for that and you may be able to find a data sheet on it. 
Okay. The part number is 247718/244247. I'm looking it up now.
I tried that procedure and it didn't work
1.) Use an ohmmeter to identify windings on the core.

2.) Build a little audio oscillator, keep the output voltage low, and then apply the output to a pair of wires on the transformer.Use an oscilloscope to identify the outputs, in conjunction with part 1.
3.) The levels measured will help you judge turns ratios.


Steve