Kino Flo replacement components

[zx81]

Can anyone suggest a replacements for?

1. N Channel Mosfet P20NM50FP
2. NPN Transistor J5027-R

I can't find any stock in the UK

I am trying to repair a 4 bank 4ft film florescent lighting ballast. It's a copy of a Kino Flo. Hi res picture of board attached.

I've removed some other components that were visually burned out and also testing all the other components before I pop in replacement transistors and Mosfet.

Could you guys also shed some light on how to look into equivalent or replacement parts when the originals are unavailable? What criteria should I be looking at in replacement parts ?

Sorry I'm very new to electronics and your input and advice would be very appreciated.

zx81.

[zx81]

Re: Kino Flo replacement components

Pls help guys.

[paulstef]

Re: Kino Flo replacement components

For the MOSFET:

Go to ALLDATASHEET.COM. Find the datasheet. Write down the following parameters:
-RDSON
-MAX CONTINUOUS DRAIN CURRENT
-TOTAL GATE CHARGE
-VDS MAX
-package
-special characteristics

Also interesting: -gate threshold voltage

Now go to digikey.com.

Search for MOSFET in the search field. Under "discrete semiconductor products" click on "FETs Single". then narrow down possible replacements by excluding all options that don't fit.
So you select all N-channels, all VDSS above 550V, all RDSON lower/equal 200mOhm, ID all equal or above 20A. Multi-select with SHIFT and CLICK etc.

For your particular case this gives 3 pages of results. When choosing packages select everything called FP or ISO.

Same goes for other components.

[zx81]

Re: Kino Flo replacement components

Paulstef thank you for coming to the rescue once again.

[Longbow]

Re: Kino Flo replacement components

I've removed some other components that were visually burned out and also testing all the other components before I pop in replacement transistors and Mosfet.

Are these two items faulty? Which other parts did you find burned?

[zx81]

Re: Kino Flo replacement components

Are these two items faulty? Which other parts did you find burned?

Hi Longbow,

I have so far removed one resistor and one small capacitor from the top side picture previously attached.

I should have mentioned and provided a picture of the other side of the board too. So apologies for that and I'm attaching a picture of the other side of the board now.

This is just one of 4 banks inside the ballast so I can get the values and compare measurements to the working banks.

The small smd resistors near the damaged transistors and mosfet also look like they will need replacing. Looks like they've been running hot as the identification text is no longer clearly readable.

Not sure on how to test the small smd transistors Q1 and Q2 they are tiny and I don't have the skill level to remove them for testing.

[zx81]

Re: Kino Flo replacement components

I have 4 of these Kino Flo lighting kits.

2 original ones made by Kino Flo and 2 imitation Chinese ones.

What I've noticed is that the original Kino Flo kits drive the lamps harder and are about 25% brighter than the Chinese clones. Is there any way to modify the clones to get the 4ft florescent tube brighter ?

The clones are for rentals and get bashed about the original Kino's are used in our studio.

Which components would I need to modify ?

Here are some links to the schematics :

http://kinoflo.com/Top%20Buttons/Sup...ast_Board.html

[japlytic]

Re: Kino Flo replacement components

The "J5027" transistor is a FJP5027 and the "P20NM50FP" MOSFET is an isolated package STP20NM50FP.
I also recommend replacing both 200V snap-in electrolyic capacitors with long life Chemi-Con units if the replacement MOSFET and transistors work.

[zx81]

Re: Kino Flo replacement components

Thank you Japlytic