Identifying a unmarked transforrmer?

[stuee]

Hi, can someone help me, i have a $1200 laser i use for my discos but its died.
It keeps popping fuses.
I messed around with it and found when i remove the transformer the fuses nolonger pop.
The layout is like this

Power in > to sideboard > direct line out to xformer (both brown wires to red wires out) / another line out to 240v laser unit / line in from transformer (redwires) following the track of the red wires on the main side board they go to 3 black / silver diodes > 16v 2200uf cap then trough to some ics AT89c52 / td62084ap..
Wil lsend images when the missus brings back camera..

Howe i found iot it was the xformer was unhooked the wire to the xformer (brownones) no fuse blew. put them back in and unplugged the red wires that go back into the side powerboard and it still blew.

If anyone has any idea how i can find out what this is i would most appreciate it..
Thanks
Stu

 

[prateeksikka]

hi there stuee!
Any type of fuse can blow up only when the current rating of that fuse is exceeded.this can further be mainly due to 2 reasons:
Firstly,the xformer chosen by you is not of appropriate rating.i.e it is of lower rating.
Secondly,you are connecting the stepdown xformer in opposite configuration.
i.e low voltage side towards the supply and highvoltage towards ur laser circuit.
low voltage side draws more current and hence blows the fuse. ;D
prateek

 

[stuee]

Hi thanks for your reply, this isnt actually a project but a purchased item. ive had it a year or so now so warrenty is expired. its not been messed with atall, it jsut popped the fuse. and did it again and again..
So thats why im trying to fix it
Thansk
Stu

 

[stuee]

I am no expers but i chased up the info on the ics onboard and they run no higer than 15v. attached areimages of the ic specs and the side powerboard. please someone help, i ahve a gig on in 2 nights and need to get this working.
Could i perhaps get a varaible selectable psu AC and power up the thing - the transformer, and hook up the ac powersupply, then gradually nock it up a setep till something happens, so i know which is the right power supply?
Thanks
Stu

View attachment 37011

View attachment 37012

 

[stuee]

Its not the cap.
Like i said how i found out it was the transofrmer was

Plugged in the power. blew fuse
Un plugged the transformer 240v input from the board. No fuse Blow
plugged back in the transformer to the board 240v. and unplugged the 2 red wires from the output of the transformer off the main board and fuse blew.
So to me that says the transofrmer is the problem.
Thanks
Stu

 

[stuee]

Thanks fopr that, didnt know i could send through DC too, 
Also how would i determin the current? could i possible but say 2 higher amp xformer in its place so i cna take what it wants or does it need to be the roughly exact to what it needs.
Also say i find it uses 9v dc that im testing it with would that mean i could buy a 9v AC and hook it up.
Thanks
Stu

 

[prateeksikka]

hi there!
i still feel that the problem lies with your transformer,try with a new one.
Thinking that the problem is with the fuse,dont remove or replace it if it is getting blown up,otherwise it is dangerous for your costly kit ur 1200$
are in jeopardy!! ;D Do tell me the results with a new x former in correct configuration.
prateek