[cncuser1]

I have a G540 on the way and a Sieg X2 with a brushed DC motor on hand.

I would like to get spindle rpm control Ideally via mach 3/4.

Does anyone know of a clear wiring diagram? Including the existing stock speed controller?

These forums have alot of posts, some with text about specific wiring connections, grounnding problemms and escaping smoke, but it is difficult to understand without the parts on hand.

I also can't be sure if I need something like a KBLC-19M controller in addition to the stock controller or to replace the stock controller.

Any help would be appreciated.

[dazp1976]

I have a G540 on the way and a Sieg X2 with a brushed DC motor on hand.

I would like to get spindle rpm control Ideally via mach 3/4.

Does anyone know of a clear wiring diagram? Including the existing stock speed controller?

These forums have alot of posts, some with text about specific wiring connections, grounnding problemms and escaping smoke, but it is difficult to understand without the parts on hand.

I also can't be sure if I need something like a KBLC-19M controller in addition to the stock controller or to replace the stock controller.

Any help would be appreciated.

I've been asking the same thing with no answers.
This is as far as I've got on paper:

Just remember this has not been tested.

X2 diagram

Possible solution:

[cncuser1]

Thanks dazp1976.
A few questions:
1- Can you identify the controller in the picture (maker, part number etc)
2- Why is there a red box around the potentiometer
3- Why is there a relay and how is it connected.
4- Can you attach a higher resolution version of the second file, I can't read the small text near the controller or relay.

[rcheli]

I have a Sieg X3 and I would assume the X2 would be similar. The potentiometer circuit must be optically isolated from ground. That may be what the red outline is indicating. If that circuit gets connected to ground it will blow the speed control board in the mill. You might check out this guy's site MINI LATHE - MILL BOARD REPAIR SERVICE and click on CNC interfacing. If you do blow your board he should be able to fix it and his service is great. You will need to disconnect the manual potentiometer and on/off switch when you connect the speed control board to the interface card.

When I converted my mill I used a Mesa 5i25+7i76 cards and LinuxCNC. The 7i76 card has an optically isolated simulated potentiometer device to control the speed. One thing I to ran into was that the speed control board did not provide enough current to the simulated potentiometer circuit and I had to add a separate 12 volt power supply. This must be a separate supply and not 12v from the interface card. I used a small wall pack and connected across the P1 & P3 terminals

This was the advice I got when doing my conversion:
The key thing to look for is a variable output voltage (0-12 volts) that is optically isolated from ground. If your board can output that, then you will be OK. What gets everybody in trouble is trying to make a direct connection to P1-P2-P3 on the XMT board which will fry everything unless they have optical isolation.


Good luck
John

[john-100]

warning

on spindle control boards like the XMT2360 the potentiometer terminals P1 , P2 , p3 are LIVE !

Attachment 402538

the FC250J used on my lathe or KB electronics KBLC-240D and its clones
found in some other mini lathes and mills
are also LIVE !!

your breakout board has a problem when connected to a live board like the XMT2360

Attachment 402540


the 5 input circuits and PWM to analogue DC converter is powered by a common 10V regulator !



John

[rcheli]

Good point John-100. When 0-10v is specified it doesn't necessarily mean that only 10 volts is involved. It just means there is a 10 volt difference between the P1 & P3 leads. The difference between either of those leads and ground may be 120volts. They are at mains level. So absolutely be careful. That is also why it blows the board if you ground them.

John

[cncuser1]

john-100 can you explain what you mean by Live?
Also can you explain what is the importance of being powered by a common 10V regulator?

Could you use some ELI5 language/explanation?

[john-100]

this is an example from KB electronics of a board with no mains isolation

Attachment 402544

if R3 is set to minimum resistance
P1 on the potentiometer is connected to the negative terminal of a mains powered bridge rectifier

in my part of the UK the mains supply is 248V RMS
so P1 has -350V pulses on it on the negative going half of the mains cycle
or + 318V on the positive going half of the sine wave

John

PS
the Live wire to me is what is called the Hot wire in the US

the negative DC supply to the input opto-isolator circuit is common to the PWM to DC analogue contol

if you connect the analogue output to P1 & P2 on a spindle control board like the XMT2360
or KBLC-240D above

the common terminal to your limit switches and E-stope switch will be connected to the negative output from a mains rectifier

if the 12 to 24V DC supply to the BOB is isolated from the mains earth / ground
then you will get a shock if you touch the limit switch wiring

if the DC supply negative output is grounded
a large fault current will damage the BOB and spindle control board unless your using a RCB/GFI circuit breaker to detect earth leakage currents

[cncuser1]

rcheli When you say "The difference between either of those leads and ground may be 120volts".
Where would I look to know that ? Is it in the specs or is it common knowledge amongst electronic pro's?
Is it common practice to actually verify all Inputs and outputs relative to ground before actually connecting them?

[john-100]

I would say its a mixture of all 3

depending on the manufacturer it may or may not be spelt out

example from KB electronics
Attachment 402548

yes
its some thing you should know about if you are an " electronics pro"
and should double check for a voltage at the potentiometer terminals

John

[rcheli]

rcheli When you say "The difference between either of those leads and ground may be 120volts".
Where would I look to know that ? Is it in the specs or is it common knowledge amongst electronic pro's?
Is it common practice to actually verify all Inputs and outputs relative to ground before actually connecting them?

I’m not a pro it is just what I was told when was connecting my machine up. I wasn’t specifically told the voltage, just that it was at mains level. I. The U.S. that would be 120. Could be more elsewhere. I accidentally bumped ground with one of those leads and it blew my board instantly. Point is, be careful. It can be dangerous.

[dazp1976]

Like I said, I haven't tried it yet.
Need to get the voltmeter out.
P1 shows as power to pot (12V)
P2 shows as the regulated 0-10v from pot back to speed controller
P3 shows as ground

As far as I've read on here
If a voltmeter put on P1+ and P3- shows 12V DC then you should be able to connect the speed control as:
0-10v + to P2
0-10v ground to P3
Leaving P1 empty.

If you get any other reading across P1, P3 other than 12V DC then it's a no-go.

On the other block 1-7 it shows as pins 3 & 5 to be the motor on/off switch from the pot.
I've seen diagrams of this connection either bridged for permanent 'ready' & wired via relay for on/off activation.
I've also seen it wired via a C7 board somewhere.
I haven't got round to properly looking just yet, the diagram was just really to show the X2 board layout mainly.

However the idea of the relay I had in the diagram was going to be for connecting to the overload light.
When the motor stalled and the light came on this would activate the relay and be connected to E:stop in Mach3 to shut the lot down.
That was the plan.

[john-100]

its not the voltage between P1, P2 & P3 that's critical

its the voltage between the Mains earth / ground and P1, P2 & P3 that matters

when using the BOB shown in post 2


if you are using an isolated PWM to analogue DC control board
like CNC4PC's C6 board powered by its own isolated power supply
or
the converter in a Geckodrive G540 thats powered by the speed control board
you are safe

John

[cncuser1]

John-100 I do have a G540, so I can just use a DC controller, like a KBLC-19M,?
I would completely remove the Sieg controller and wire the KBLC-19M directly to the stock Brushed DC motor.

I think this would allow Mach4 to control the RPM right/?It seems to me the stock control board complicates the situation for no reason.

[dazp1976]

its not the voltage between P1, P2 & P3 that's critical

its the voltage between the Mains earth / ground and P1, P2 & P3 that matters

when using the BOB shown in post 2


if you are using an isolated PWM to analogue DC control board
like CNC4PC's C6 board powered by its own isolated power supply
or
the converter in a Geckodrive G540 thats powered by the speed control board
you are safe

John

The 5 axis board with relay shown is isolated on that side and needs a separate 12v-24v psu to power the relay/pwm control. So I'm assuming that it will work then?
It wasn't clear that it was isolated from the rest.
There are 2 options with that board you can either 1. use the isolated side with a supply or 2. use P17 into a C6.

[john-100]

if the KBLC-19M is a variation of the KBIC controls - yes


from a post on CNCZONE the circuit of the G540 PWM to analogue converter

Attachment 402584


from the G540 manual

ANALOG OUTPUT: This is a 0V to +10V opto-isolated analog output intended for use with VFD drives. VFD OUT goes to 0VDC while the G540 is disabled. Connect VFD GND, VFD OUT and VFD +10V to the VFD drive inputs. Make sure the VFD drive positive voltage does not exceed +12VDC. Do not short VFD OUT to any other terminal. Do not reverse polarity to VFD GND and VFD +10V or the G540 may be damaged.

as long as the maximum voltage across the terminals that the speed control potentiometer has been removed from
the G540 can be connected

Attachment 402586


John

PS

Hi dazp

with BOB's like this
Attachment 402588

the connections to the motor control board are isolated from the PC printerport or motion controller
but any live connection to the analogue common makes the linit switch common live as they are connected together on the PCB

[dazp1976]

I'll get the multimeter out when I get the chance and go over it all. Double/triple check everything is within perimeters.
The way I think I'd go about mine is to bridge the 'spindle on' switch part so the X2 is always 'ready' and use the board relay to activate the coolant pump when Mach calls M3.
I did read that there isn't enough delay in Mach between calling the M3 & S--- commands for the X2 to operate correctly via the relay on/off.
So at least the pump would make use of the otherwise useless relay.

[john-100]

remember to put your meter on its 300 V DC range when you check the voltage between earth and the potentiometer terminals

on the AC range the digital multimeter will ignore the pulsing DC voltage !!!!!!

John

[cncuser1]

John, regarding the sketch of the controller and G540, relays PSU's, etc, the mains voltage components should be grounded? What about P1/GND, should that be grounded also?

[john-100]

the G540 terminals 7 , 8 & 9 must only be connected to the motor control terminals P1 , P2 & P3


the G540 power supply negative terminal can be connected to the mains earth
Attachment 402600

in the diagram the PSU negative terminal becomes the "star point" earth

if your using switch mode power supplies with the negative terminals connected together
the leakage currents due to the EMI filters demanded by the european comunity regulations ,can be a shock hazard
(yes, I know the hard way its enough to shock you
its a trap others can leave for you !!!)

the addition of an earth connection can provide an alternative path other than you

John