Re: G540 to Consew Type Servo Sewing Machine Motor
Hi Ron, thanks! I'm working with the basic green opto isolated "5 axis breakoutboard" you see everywhere. Upon further inspection I saw that this too needs external power to provide the analog 0-10V for the spindle control. So maybe it indeed boils down to the same situation as with the g540. I feel warned though by John as he stated the connections at the 5V input of the Consew controller could very well be live. Zapped myself once before during reinstallation of a bandsaw motor controller.housing....
4 Attachment(s)
Re: G540 to Consew Type Servo Sewing Machine Motor
if your BOB is like this
Attachment 386924
from the photo it looks like a cut down version of the TX14175 example in post 17
and will be like this
Attachment 386932]
a 5V supply from a USB port powers the IC's that connect the printer port to the stepper drivers
a 12 to 24V power supply is reduced by the on board 10V regulator that powers the LED's in the 5 input opto-isolators that you connect your limit switches & e-stop to and the PWM to analogue converter circuit
this is inter connection between the limit switches & VFD is a possible danger depending on your speed control board
for example the FC250 board used in the CL300M mini lathe would make any limit switches live !!
as the FC250 board has the speed control potentiometer connected to the positive terminal of the mains bridge rectifier
FC250 speed control
main board
Attachment 386928
daughter board
Attachment 386930
john
Re: G540 to Consew Type Servo Sewing Machine Motor
Hi John,
Yep that's the one. In the meantime I've joined the taig facebook group because the sewing servo's are a really popular replacement for mini mill and lathe type stock motors. There was quite some discussion about driving a consew type motor from software. Unfortunately I didn't really see people talking about the "live" connections. I did see that some people over there are using a little "voltage to current isolation transmitter circuit" between the breakoutboard and the consew controller that converts 0-10V to 4-20mA which together with a 250 ohm resistor would deliver the 1-5 volt range that the consews like to have. Voltage to Current 0-5V/10V/15V to 4-20mA Isolation Transmitter Signal Converter | eBay
Does this solution also provide some kind of isolation from the dangerous voltages?
Re: G540 to Consew Type Servo Sewing Machine Motor
I can not see any opto-isolator on the 0-10V to 4-20mA board to provide any isolation
as I have not used or worked on a Consew board , I would need comfirmation the potentiometer connections are isolated from the mains
may be someone at the taig facebook group could confirm the consew input is isolated
that's why I looked at the CNC4PC's PWM to analogue boards
john
Re: G540 to Consew Type Servo Sewing Machine Motor
Hi John, I can confirm that the consew connections are indeed unisolated! Someone already has fried his G540 because his multimeter probe slipped and touched a part outside the isolated circuit. I'll stick to manual control.
Re: G540 to Consew Type Servo Sewing Machine Motor
I expected that would be the case
Working on line equipment all ways concentrates the mind !
I'm not sure heath & safety will allow it these days
but as a 18 year old apprentice I had a job rewiring vibrators that kept powders in a mixing room flowing
one at a time , each had to be disconnected from a live 240V mains supply and then connected to a new live circuit !!
John
Re: G540 to Consew Type Servo Sewing Machine Motor
What?! I'm not sure today's peoples attention span would allow having such a job either (including myself ;)).
Re: G540 to Consew Type Servo Sewing Machine Motor
this video of men working on live power lines makes my working on broadcast television monitors look safe (EHT for the CRT is only 24KV)
https://youtu.be/GxDKVAYJ_t4
John
Re: G540 to Consew Type Servo Sewing Machine Motor
LOL My god, that's a ballsy endeavour. Respect
Re: G540 to Consew Type Servo Sewing Machine Motor
Ron Thompson: could you post a higher resolution file of the schematic ? The version you posted is very hard to read and the Yahoo group has been cancelled.
Re: G540 to Consew Type Servo Sewing Machine Motor
I don't have a Taig mill or a Consew motor any longer. But the info is still available on the Facebook group. https://www.facebook.com/groups/Taig...nd.Mill.Group/
Re: G540 to Consew Type Servo Sewing Machine Motor
Thanks Ron Thompson.
Can you give a few words on how it worked or didn't, max cutter size, performance, rpm stability etc?
Re: G540 to Consew Type Servo Sewing Machine Motor
I don't remember much about it. It worked using Mach3 to control the spindle speed and was a very strong motor. I used it mainly to do away with the skinny belts. Ask on that group and they can tell you all about it. I bought a Haas and haven't looked back.