[VTX1800]

Greetings all,

Has anyone used the Dynomotion KFLOP motion controller board to retrofit an AXYZ router with 4 stepper motors?
Looking at the KFLOP board, the KSTEP 4 Axes board and the Konnect Optical IO board.

Advice, recommendations, and suggestions are really appreciated.

Thanks in advance,
Ted

[TomKerekes]

Hi Ted,

Have you found the specifications for your Stepper Motors? Resistance? Inductance?

Regards

[VTX1800]

Hi Tom,
I sent you this information in an email but hopefully others may chime in with more information.

I also found some calibration details regarding the motors.

X=1273.28 steps/inch
Y=1273.28 steps/inch
Z=10000 steps/inch

X=1000 steps/rev
Y=1000 steps/rev
Z=2000 steps/rev

Acceleration (inches)
Linear 1.608
Centripetal 0.501

Min Line length 0.009
Arc error 0.005

Feed rate max (inches/min)
Linear 394.4
Plunge 49.97

Corner pause 0.059 sec

Motor label:
Model PST341-3A
Current 5.0 Amps
Voltage 1.45 volts
1.8 degs.

4PS Precision & Speed Ltd.

Regards,

Ted

[TomKerekes]

Hi Ted,

Motor label:
Model PST341-3A
Current 5.0 Amps
Voltage 1.45 volts
1.8 degs.

Normal 200 steps/rev Stepper motors.Those are fairly low voltage motors (1.45V). The Motor Supply Voltage for KSTEP should be limited to ~15X the rated motor voltage which would be ~24V in this case. Can you measure your supply voltage?

X=1000 steps/rev
Y=1000 steps/rev
Z=2000 steps/rev

These are somewhat odd values. Since your motors are 200 full steps/rev (1.8 degrees) those would be 5X and 10X microstepping. Most drives do powers of 2 (half, quarter, 8X, 16X, 32X, etc...). KSTEP does 16X so KSTEP should be a step up in resolution an smoothness.

X=1273.28 steps/inch
Y=1273.28 steps/inch
Z=10000 steps/inch

Those indicate a resolution of ~ 0.8 mils for x and y (much higher for Z). As well as about 0.8 inches for each motor revolution for x and y. Does that sound correct?

Feed rate max (inches/min)
Linear 394.4
Plunge 49.97

394.4 inches/min x 1.273 revs/inch = 500 RPM (shouldn't be too difficult to achieve)

[VTX1800]

Hi Tom,
Just got back to see your note.
I measured the DC voltage to the Pacific Scientific 6410 amps.
45 VDC.

I found a very basic electrical schematic that showed the input transformer and two outputs to bridge rectifiers.
One was labelled 40 vdc and the other 12 vdc.

I also measured about 5 vdc across one phase output to a motor.

In your comments you stated 200 steps/rev.
The calibration data in the manual states the following:

X=1000 steps/rev
Y=1000 steps/rev
Z=2000 steps/rev

Lastly, your observation regarding a minimum of 50 usec stable direction signal requirement for the 6410 was not possible with the KFLOP motion controller.
With all the C programming and custom features available I am surprised the duration of this signal cannot be adjusted as needed.

Ted

Hi Ted,


Normal 200 steps/rev Stepper motors.Those are fairly low voltage motors (1.45V). The Motor Supply Voltage for KSTEP should be limited to ~15X the rated motor voltage which would be ~24V in this case. Can you measure your supply voltage?

These are somewhat odd values. Since your motors are 200 full steps/rev (1.8 degrees) those would be 5X and 10X microstepping. Most drives do powers of 2 (half, quarter, 8X, 16X, 32X, etc...). KSTEP does 16X so KSTEP should be a step up in resolution an smoothness.

Those indicate a resolution of ~ 0.8 mils for x and y (much higher for Z). As well as about 0.8 inches for each motor revolution for x and y. Does that sound correct?




394.4 inches/min x 1.273 revs/inch = 500 RPM (shouldn't be too difficult to achieve)

[TomKerekes]

Hi Ted,

I measured the DC voltage to the Pacific Scientific 6410 amps.
45 VDC.

I think that would be too high for KStep with those 1.45V motors. 24V 400W switching supplies are very reasonably priced (~$50).

I also measured about 5 vdc across one phase output to a motor.

The Voltage should be switching so a Voltmeter may give unpredictable results. If you add an RC filter you can get a reasonable measurement (ie 1K 10uf).

n your comments you stated 200 steps/rev.
The calibration data in the manual states the following:

X=1000 steps/rev
Y=1000 steps/rev
Z=2000 steps/rev

The first is the full steps of the motor. The others are after microstepping by the drive

Lastly, your observation regarding a minimum of 50 usec stable direction signal requirement for the 6410 was not possible with the KFLOP motion controller.
With all the C programming and custom features available I am surprised the duration of this signal cannot be adjusted as needed.

We made a mistake there in our design to not consider slower drives. We had in mind drives that accept high step rates (2.5MHz). High end drives don't usually have such a requirement. It turns out to be awkward for us to change at this point. Actually we are working on a change to extend our Direction Setup Time from 4us to 5.7us because there is one popular drive (Leadshine) that require 5us.

Regards

[VTX1800]

Hi Tom,
Thanks for hanging in there.
Where do these observations take us?

Does implementing the KFLOP solution require the following:
KFLOP board
KSTEP4 board
Konnect Opto Iso board
1 unregulated power supply for the KSTEP and ultimately the stepper motors (amps?)
Regulated 12 and 5 volt supplies for KFLOP and IO boards. (recommendations?)

other components, relays, etc?

Total cost estimate?

Thanks,

Ted

[VTX1800]

Hey Tom,
Just wondering...
In all your previous customer applications has anyone accomplished a retrofit like this on a commercial CNC stepper router?
I was hoping someone on the cnczone forum had some practical experiences to share.

regards,
Ted

[bhurts]

Dynomotion Kflop Kanalog - YouTube

This is a youtube video of a dynomotion router retrofit. Search dynomotion / k-flop on YouTube and you will find many other machines as well.

Ben

[TomKerekes]

Hi Ted,

Does implementing the KFLOP solution require the following:
KFLOP board

Yes - $249

KSTEP4 board

Yes one KStep $199

Konnect Opto Iso board

May not be needed

1 unregulated power supply for the KSTEP and ultimately the stepper motors (amps?)

Actually I'd suggest isolated Regulated 24V 360W (15A) or higher ~ $50

Regulated 12 and 5 volt supplies for KFLOP and IO boards. (recommendations?)

12V isn't required. Usually 24V isolated is used for limit switches (1Amp or higher). 5V isolated (2A or higher) = ~ $30

other components, relays, etc?

Its up to you to design the interface for any other requirements for your system. KStep provide 2 isolated relay drivers normally used to control a Spindle. Those can act as relays themselves if the load is 24V or less and 0.1A or less. For higher voltage/current they can drive an appropriate relay. KStep provides 16 24V inputs which is enough for most routers. To add screw terminals for the KStep I/O add a 3rd part breakout board such as this ($19) :
2x13 0.1" Header (26 position IDC ribbon connector) Breakout Board with Screw Terminals - Winford Engineering

Hey Tom,
Just wondering...
In all your previous customer applications has anyone accomplished a retrofit like this on a commercial CNC stepper router?
I was hoping someone on the cnczone forum had some practical experiences to share.

Not sure exactly what you mean by "commercial CNC stepper router". Most bigger systems have servos.

Carl Bruce makes some nice routers using KFLOP/KStep. Here is a satisfied customer of his:
http://www.cnczone.com/forums/commer...ml#post1148317

Some bigger systems:

https://youtu.be/fTj5MGc5pl0

https://youtu.be/u9EbqIAQ8mE

https://youtu.be/n1j8s5AdRm0

https://youtu.be/QtJ6sj-MOgw



HTH
Regards

[VTX1800]

Tom,
Ordered and received a large computer server power supply for the 48V motor power and 12V KSTEP IO power.
This specific item was recommended by another KFLOP/KSTEP user who has been running for several years.
Ordered and waiting for the appropriate connector and an additional regulated 5V power supply.
Purchased the Winford 26 wire breakout board to connect to the KSTEP board.

Looked at the AXYZ router original X, Y, and Z home limit sensors.
These are proximity sensors with three wires.
Nominal 15V, gnd, and signal.
Signal goes high when mechanical stop block is within sensor range.
Have these proximity sensors been successfully used with the 12 volt KSTEP IO?

regards,

Ted

[TomKerekes]

Hi Ted

Ordered and received a large computer server power supply for the 48V motor power

In two earlier emails I suggested not to use more than 24V with your 1.45V motors. Did you read those emails?

Looked at the AXYZ router original X, Y, and Z home limit sensors.
These are proximity sensors with three wires.
Nominal 15V, gnd, and signal.
Signal goes high when mechanical stop block is within sensor range.
Have these proximity sensors been successfully used with the 12 volt KSTEP IO?

The KStep documentation here:
KStep Connectors

Shows the KStep Opto Input circuits as Resistor+LEDs with common Anode (+ terminal to + supply). The supply must be common to all inputs. It may be +12V, or +15V, or +24V. I don't understand why you would buy a +12V supply if you knew you had +15V proximity sensors.

Attachment 281710

The individual inputs must sink current to ground as shown in the diagram to turn on the KStep LEDS. If your switches drive high to +15V that would be ok, as long as they also drive low to near zero volts while sinking the LED current. If you can tell us if your sensors will sink current to GND then we can tell you they will work with KStep opto inputs.

Attachment 281708

HTH
Regards
TK

[VTX1800]

Tom,
Yes I read your emails several times and examined the existing motor power supply on the AXYZ router.
The actual measured motor supply of the 5 amp NEMA 34 motors is 45-46 volts.
Since the original designers purposed a 46 volt motor power supply with 20 amp fuses, a 48 volt power supply is very close.
Additionally, another KFLOP/KSTEP user with a very small gantry and three NEMA 17 motors is using this supply.
The very large gantry on my machine weighs 10 times what his router gantry weighs and uses four stepper motors.
He is also using 240 VAC instead of 120 VAC to get the maximum current capability from the 48 V output.
100-120 VAC 13.5 amps
200-240 VAC 20 amps

Additionally, I do not have the specifications or even the manufacturer of the proximity sensors.
I mentioned the AXYZ company is not forthcoming with any information for this machine.
However, many proximity sensors operate over a range of 10 to 30 volts.
I posted these questions here to learn if you or someone on this forum have used these sensor types with KSTEP inputs successfully.

If you know of a cylindrical proximity sensor that will work with 12V KSTEP inputs I am willing to replace the three sensors on the router.

Lastly, is there anyone on this forum that has used KFLOP/KSTEP boards to retrofit an AXYZ router?
Since AXYZ does not support their own older machines this could impact many owners of AXYZ routers.
AXYZ and MultiCAM are two of the larger router manufacturers with thousands of units in the field.

Ted

[VTX1800]

Tom,
Another observation...
I opened the control panel and traced the limit sensor cables to the connection board.
The connection board has LEDs for each of the X, Y, and Z limit sensors.
Therefore, it is reasonable to conclude that the sensors are sinking current for these LEDs.

Next week I have a large job to do with the existing hardware before I start the retrofit with the KFLOP and KSTEP boards.
I propose testing one input to the KSTEP board with a signal unless you have concerns.

Alternatively, do you have a specific recommendation for a replacement cylindrical proximity sensor that is known to work with a 12V KSTEP input?

regards,
Ted

[bhurts]

I don't know of a good source of round sensors that are proven working. I don't use kstep instead I use snapamp. I would check with Tom to make sure but assume the opto inputs on snapamp and kstep are the same. If so I use these.

CNC4PC

They work very well and I know at least one other user is using them also. Here is a link to his thread and I think it may be useful to you. You can search his other threads for a diagram to how he wired them which is the same way I did.

http://www.cnczone.com/forums/dynomo...ml#post1684550

Ben

[VTX1800]

Hello Ben,
Thanks for the response.
I am familiar with the CNC4PC web site.
The sensors shown are probably similar in function to the cylindrical ones on the AXYZ router.
A close up picture of one sensor shows an operating voltage of 5 to 30 V, PNP, with the signal state NC.
The AXYZ router table is 4' x 8' so the cables are really long.
Hope I do not have to replace them.

I really appreciate the link to the user jossa thread regarding his KFLOP and KSTEP startup.

I will look for a jossa post where the wiring is described.
Should be ready to start the retrofit after next week.
Still getting components.
Considering VCarve Pro software from Vectric.

Cheers,
Ted

[bhurts]

The cables on the sensor are only 6 feet or so. If your existing sensors are 3 wire cables you can either splice new ones to the old cables or probably just use the existing sensors.

Ben

[VTX1800]

Tom,
I was able to get a part number for the proximity sensors from the parts person at AXYZ.
The part is not available but I was able to find a data sheet on the Internet at the following URL:

IA08BLN25POM1 (Carlo Gavazzi) - 3-wire DC (2.5 mm)

Attachment 281758

Ted

[VTX1800]

Tom,
The sensor is type PNP and make switching or normally open.
regards,
Ted

[TomKerekes]

Hi Ted,

I suspect you will have microstepping problems with the 48V supply if your motors are 1.45V motors. The voltage required for 1/16th of a step would be:

sin(90degrees/16) x 1.45V = 0.14V

To maintain this voltage using a 48V supply is a bit beyond KStep's capability as I explained earlier. It is a fairly complex technical issue involving the driver chip with regard to fixed off time, blanking time, dead time, and slow/mixed decay modes. See here for more info. You might think of it as trying to fill a teaspoon of water by quickly switching on and off a fire hose. Other drives may handle this better. Did the other KStep User specify what voltage his motors were? You can return KStep if you wish and use other 3rd party drives.


Regarding the Proximity sensors: The one you listed is a PNP type (switches to +). KStep inputs are designed for NPN type (switch to - as shown in the diagram I attached) and would not normally work. The sensors are specified to switch relatively large currents (200ma) to +. They are not designed to switch to - at all and do not specify if they do at all. KStep Opto inputs only require about 1.5ma of current. If they happen to sink that much current to - they may work. You could guarantee they would work by adding an external 1Kohm 1/4 watt (or higher) pull down resistor to -.

Regards