Maker Pro
Maker Pro

PSU transformer repair completed

roughshawd

Jul 13, 2020
264
Joined
Jul 13, 2020
Messages
264
I have an old psu from some thing that was put in the operating pile in 2007. It has a two button, momentary interupt (gel button) board that plugs into it which has some kind of action that it is supposed to perform when the device is turned on with a second, push to activate - positive on positive off - start button. I am fairly sure the PSU will work, when I get the resistors put back on the board and figure out what the buttons do...!!! Anyway one of the secondary wires was corroded at the pin and I soldered an extension on to it so that it would reach the pin. It was at the start of the winding, buried under the coil, so I couldn't just remove a couple wraps. The primary on the transformer is 110v and the secondary is 10v according to a neat little sticker tape that was on it when I pulled it. . Nice little transformer! The board is fused and has a buzzer on it... worth saving!

My question is kind of moot as usual... far be it from me to tell a professional how to build their PSU...
Personally I would never build a 220v board with 110v parts... that seems a bit too inexpensive...
But transformers are not inexpensive at all. so why put a 110v transformer in a 220v system?

These asian boards were mass produced and probably have no records of their manufacturer or schematics that are available to us U.S. junk dealers. This board has a T15/250A AC fuse on it and all the relays are 250v 10a. Does this mean that the board was probably designed to be used in Europe or Asia, and maybe someone used a 110v transformer instead of a 220v transformer on it
???
 

Martaine2005

May 12, 2015
4,399
Joined
May 12, 2015
Messages
4,399
The ‘240V’ is just the maximum voltage the component is rated for. It can happily be used on lower voltages too.

Martin
 

roughshawd

Jul 13, 2020
264
Joined
Jul 13, 2020
Messages
264
One other small thing!!! There are supposed to be 2 red leds on the button board. They have long since been smoked. They sit atop little towers that lift them up. I am assuming these are 2007 era red LEDs and they are probably the standard small factor diodes. the outside led is activated by the left middle pin orange wire in the 6 pin female connector on the button board. The other to the white wire pin CN1 #3 and #5. I would then probably say that the white wire is probably a run power led and the orange an accesory or condition indicator. Were there special specs for the LED's on 2007 button boards? I have seen lots of different types of leds in post millenia driver boards. #2- how would you go about repairing that corner break on the board? I am thinking superglue + baking soda without graphite, then a 90 degree strap around the corner between the two missing section? Note for webmaster : sorry for the large pics. I will use thumbs for the rest of my images. IMG_20221129_103257915.jpgIMG_20221129_103305355.jpgIMG_20221129_103321678.jpg
 

roughshawd

Jul 13, 2020
264
Joined
Jul 13, 2020
Messages
264
When I was fixing the J2 jumper, I lost hold of my tweezers and it flew away to where old jumpers go when they die. I replaced it with a solid copper jumper that solders directly to the repair strap. What should I use as a filler to seal the repair?IMG_20221129_115658939.jpgIMG_20221129_115735947.jpg
 

roughshawd

Jul 13, 2020
264
Joined
Jul 13, 2020
Messages
264
optional ducktape method! notice the extra backing used to maintain board integrity and proper function of the repair... Can be optionally removed by specialized technician and allows a holder so you don't get shocked if you are a novice.IMG_20221129_130712813.jpg
 
Top