Sanco Mill electrical issue with a transformer???

[Wolfman914]

Good afternoon
Hope I am posting in the right section if not please advise as to where this needs to go.
I recently got a Sanco Mill from a friend of mine. He said the machine never worked in his shop and I know now why he never got it running.
I hooked it up in my shop and as soon as the power is turned on a fuse inside the electrical cabinet blows.
When the door of the electrical box is open the machine has a safety switch and nothing besides the switch is powered. After the switch is closed a 10amp glass fuse nearly explodes.
The switch is connected to a transformer and perhaps acts like the main switch to turn on all the gizmos this machine has to offer through this transformer. The switch is connected to the “0” (zero) pin of the transformer. When I measure continuity between all the pins on the transformer they all have continuity to each other. This makes me think that the transformer is bad.
I attached an image of the transformer and I do believe this is the culprit. Maybe measuring it this way is not correct and somebody could provide some help here. I would highly appreciate it. This transformer also has no other information but the name “San Gom” on it. Not clear where to find a replacement for this kind of transformer.
Any pointers would be greatly appreciated.
Thank you to all in advance.
Have a great weekend
Best Oliver

 

[markba633csi]

Hi Oliver: Need a little info, is this a 3-phase machine? Can you post some pictures of the motor data plate just to clarify?
I presume this machine has not run for quite a while. It might be more practical to bypass all the existing controls and install a VFD.
It looks as though the transformer is miswired but I can't say for sure yet. What is the last terminal next to the 480V one marked?
Is there a control panel with high/low speed switches? Pics of that too would help, and pics of overall machine
-Mark
ps the transformer is probably ok, it may be an auto transformer which all pins would show continuity

 

[JimDawson]

That may be an autotransformer and would show continuity between all the terminals. But I have never seen one like that.

That panel has a lot of wires and controls for a milling machine, it must have several motors. I think a picture of the machine would be helpful. The model number of the machine would be helpful also,

 

[Wolfman914]

Thank you guys for your quick answers.
I will post pictures of the full machine and control panel on Monday when I get back to the shop. I do have the motor plate and it is below.
the machine is 3phase and wired as such. It definitely hasn’t run forever from what I can see. Also when I activate the contactors by pushing on it all motors work. There is a motor for the table up and down. A motor for the table right and left. One motor for vertical and one motor for horizontal milling. The vertical motor is a two speed and therefor has two different contactors.
I already toyed with the idea to have the vertical motor run on a VFD. It would make it much easier to change speeds in the future rather than changing the belt. The control panel does have buttons for slow and higher speed.
Thank you again for your inputs.

 

[Wolfman914]

The covered up voltage on the transformer is 575v.

 

[Wolfman914]

And the machine is a Sanco SM-G2
Here is a link to my exact machine.

SANCO SM-G2 Knee Mill - Universal Horizontal and Vertical | Milling Machines

SANCO SM-G2 Knee Mill - Universal Horizontal and Vertical from Bid On Equipment. BOE offers an extensive inventory of competitively priced Milling Machines.

www.bid-on-equipment.com

 

[markba633csi]

Well I see the main vertical motor is 220 volts but puzzling what the higher voltages are used for
Not sure how far we can get without a schematic diagram though

 

[Wolfman914]

Well I see the main vertical motor is 220 volts but puzzling what the higher voltages are used for
Not sure how far we can get without a schematic diagram though

The motor is 220v and the higher voltages have wires at the transformer but end up on the board without going any further. All I can think is that it can be setup for different voltages around the world?
Unfortunately, I got the mill without any paperwork or electrical schematic of some sort.

i thought of rewiring it all but not sure that would lead to any different outcome.
What is weird is that all the motors work when activated by pushing on the contactors. That leads me to believe that the fault might be on the control side of the machine. However, I can not find a short on any of the wires from the control board or the switches. That just leaves the transformer in my mind but then again I am far from an electrician or electronics geek. Hope I can get this sorted.

 

[Wolfman914]

Here is what I found while looking through the archives on this forum. This is definitely better than starting from scratch.
i am sure some sharp electric geek can figure this out.

 

[mksj]

There is a previous thread on this machine, evidently it was sold under Enco, Jet and probably other brands. The JET version is the HVM-1PFB.

Sanco SM-G2 (Enco, Jet HVM-1PFB) Question

Hello All, I'm new to this forum. I usually lurk in the Logan area. I'm picking up an Enco Sanco SM-G2 Vertical and Horizonal mill. It doesn't come with manuals or any information. From what I've gathered, parts are hard to come by and Enco marketed many mills under different brands. It...

www.hobby-machinist.com

The first thing I would try is to see if you are using an RPC would be to make sure the wild leg is NOT connected to the transformer, i.e. so use terminals R and T as the pass through (L1, L2) from the RPC to the transformer.