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Re: Graziano SAG12

Posted: Fri Nov 22, 2019 10:11 pm
by Tld2375
The rectifier is not a problem, I have new modern types. 24/30/32 volts does’t matter much.
The real question is, the transformer the problem or just a symptom of a bigger problem?
It is obviously smoked, and has 0 volts output and 240volts input. (Yes l checked it)
After poking around a little, l believe the control circuit is OK, with the exception of the transformer. It would be really helpful to know the resistance of some of the other things in the other circuits, such as the clutches. That is assuming the clutches are 30/32 volts from the transformer and not line voltage controlled by a contactor. I have not gotten that far yet.
Anyone have any juicy details such as that?
I can read a schematic, but testing components requires a little more.
To complicate matters, l’m getting old, and simple things aren’t anymore! :shock:

Re: Graziano SAG12

Posted: Fri Nov 22, 2019 11:34 pm
by Patio
Disconnect one of the coils, of the clutch magnets, from the system, read the resistance. This will allow one to figure out the amperage needed. Then the transformer could be sized accordingly. In fact, I think it would be a good Idea to test the resistance of all the coils to see if they are all the same, or if one has failed. You can also test the coils of the contactors the same way. The schematic shows the clutches are definitely 30/32VDC. Unless Graziano did a major redesign, and I have found no evidence of that, yours should be too. It is said that the electrical systems of their lathes were the biggest problem. There is also an electrical timer in the clutch system. I think it so only one clutch is engaged at one time. Harold says if two clutches engage at the same time, the spindle will come to a abrupt stop. Send me a PM if you want to talk it out on the phone.

Re: Graziano SAG12

Posted: Sat Nov 23, 2019 12:52 am
by LIALLEGHENY
Did a quick search on Ebay for multi tap transformers ….came up with this

--https://www.ebay.com/itm/Eltosch-120203 ... OSwGiRTq0s~

You might wind up having to replace the single unit with 2 separate transformers.

Nyle

Re: Graziano SAG12

Posted: Sat Nov 23, 2019 7:43 am
by tornitore45
Patio, my mistake.

Re: Graziano SAG12

Posted: Sat Nov 23, 2019 8:31 pm
by Patio
tornitore45, no problem. Thanks for the clarification.

Re: Graziano SAG12

Posted: Sun Nov 24, 2019 7:11 am
by tornitore45
The idea of two transformers seems the best. Standard transformers are available and inexpensive'

Re: Graziano SAG12

Posted: Tue Nov 26, 2019 11:04 pm
by Tld2375
Not much getting done, stand by ‘til after the holiday!
Thank you all for the help, and happy Thanksgiving!

Re: Graziano SAG12

Posted: Wed Nov 27, 2019 12:54 am
by Patio
It'll get done when it gets done! :) Thanks for keeping us up to date.

Re: Graziano SAG12

Posted: Sun Jan 12, 2020 7:06 pm
by Tld2375
ITS ALIVE!
Finally found some time for this. I replaced the transformer with 2 single voltage transformers and the 32V rectifier.
She's up and running again....
Apparently the rectifier had shorted out and fried the transformer. Not until I replaced the rectifier did she come alive.

Thanks All for the help!

Re: Graziano SAG12

Posted: Mon Jan 13, 2020 2:40 am
by Harold_V
Good to hear it, although I was looking forward to buying it for spare parts for mine! :lol:

H

Re: Graziano SAG12

Posted: Mon Jan 13, 2020 12:48 pm
by Tld2375
Well, next time something breaks....

Re: Graziano SAG12

Posted: Mon Jan 13, 2020 5:14 pm
by Harold_V
I'll keep a good thought! :wink:

H