Noob Help, Power Board Problems.

[tyler durden]

Hello Everybody,
This is my first post, I'm looking for a long term place to lurk so I am glad to find this site. I'm getting into small electronic projects but this time I have a stressful repair for myself that popped up and need some help.

I have an industrial printer, I went to turn it on and there was no power at all. I replaced the main fuse cause it was burnt out and then the power resister fried as soon as I plugged it in.

I need to get this thing back up and running, so I can work.

The other problem I found with my meter was a bad transistor. I don't know what caused the problem but I suspect the printer turned on for a self cleaning over night and it is possible a servo motor was stuck and blew something. That's all I can think could of happened, because it worked perfect the day before.

Anyhow, Im trying to replace parts and fix this thing.
My questions are, what is the best replacement for the burnt resistor. I can't find an exact, See pic, I don't want to cause more damage.

The transistor pictured is hard to come by, what would be a good replacement spec wise? What else should I check for, I'm very worried other parts are fried or when I put it back in It could break again or damage another board. This printer has like 5 circuit boards. Its a large roland 545ex.

I'm not good at testing, I just happen to be lucky to find the bad transistor when compared the the same one next to it. This is the power board for the printer.

Any help or suggestions welcome. I tried to find a local tech but all that you can find now are ipod repair places.

Thank YOu



Link to the Transistor I bought.
https://www.mouser.com/Search/Produ...Fvirtualkey61370000virtualkey844-IRFPC60LCPBF

 

[zsolt1]

hi,
resistor is not critical, sometimes is used like a fuse... Try to replace burnt out trazistors & change some electrolytic capacitors. First power up the supply & measure output voltages, after that try to search for shorcircuits on other boards that are supplied from this supply . (measure the plugs) If no short , it has to work.

PS: if you can also use other supplies from some pc , if you know the voltages (& power) needed.

 

[D.A.(Tony)Stewart]

I suspect the fan (not shown but directly over these faulty parts) failed with a dead-spot in one position, then secondary damage to transistor and resistor.

Otherwise. One of the boards has an over-current condition.

These Boards are selling for 400- $850 on web I see. ouch. Getting a custom supply may work if you can confirm the voltages.

If you can afford spare boards http://www.3dtechnics.com/support_smartlists/INK/ink_smartlist_05_20060627.pdf

nice grand format printer !

K2915 has lower RdsOn than what you bought. If it works but on the hot side , get SiHP30N60E-E3 125mOhm 600V