maybe i need transformer - plotter power!!!

[Clyd3]

i was given a plotter recently, a roland dxy-1200
it supposedly still works, but i do not have the transformer i need for it.
it has a 3 pin power connector, saying it needs 9v and 31v.
i take it the middle, and higher pin is the gound???
can i hook up my variable pwr supply and a separate 9v supply to this, or is it a naughty, not so wise, silly thing to do???

 

[evandude]

Unless someone here happens to have that plotter or the manual for it, nobody can say for sure which pins are which, and it's a bad idea to just guess. If you open it up, perhaps you can find some markings on the PCB or at least look at what kind of circuitry each pin goes to. Ground should be easy to identify, look for any chips in the plotter, find a datasheet, see which pins are ground, and use a multimeter to see which of the power pins connects to it. 9v and 31v will probably be trickier, but I'd expect one to go to some power/motor driver circuitry and the other to go to control circuitry.

Not knowing the current requirements of the power supply, it may not work to just hook up any old 31v and 9v power supplies to it, however if the supplies are capable of a reasonable amount of current it's probably worth a shot.

All in all, unless you can find some documentation, it would be all about making the most educated guess you can before hooking power up to it, so you don't blow anything up.

 

[Clyd3]

i followed the pcb tracks - one was easy - ground - cause one lead to 7805s and the other to twentysomething volt relay

i was scared to open it, but being such a simple shape, it all went well, thanks for the advice napoleon

 

[Hero999]

Do you know what current it needs?

Are there any fuses which might give you an indication.

It's probably quite easy to build a PSU for it, an LM317 regulator, transformer, rectifier and smoother capacitor will probably do the job.