[TomKerekes]

Announcing Dynomotion's New 4-Axis Stepper Driver - KSTEP

•Quad 240W Microstepper Amplifer
•Plug-n-Play with KFLOP
•16X Microstepping
•5A @ 48V Max
•Super High Efficiency 17mohm MOSFETS
•Opto Isolation
•Mixed Current Decay
•500K steps/sec
•Regenerative Voltage Clamping (1KW peak)
•includes 1 Opto Isolated Analog Output
•includes (16) 12-24V Opto Inputs
•includes (2) 30v @ 0.1A Opto Isolated Drivers
•$199

Order here. More info here.

[bradodarb]

That is a thing of beauty and a joy to behold! You dont have a "cash for clunkers" program for my gecko 203v's do you? JK...

Are closed loop steppers handled on this board alone or do encoder signals need to go directly through the Kflop?


-Brad

[TomKerekes]

Hi Brad,

Thanks. If you wish to run closed loop steppers with encoders you must connect those back to KFLOP. Typically JP5 would be used.

Regards,

[ger21]

Can you connect two of these to a KFLOP? I need 6 motors on my new router.

[TomKerekes]

Yes you can connect two KSTEPs to KFLOP for 8 motors. You will use the RJ45 connector from KFLOP for the second set of Step/Dir signals.

It isn't convienient or really practical to utilize the extra IO on the second board however.

Regards

[RTP_Burnsville]

Hi,

I have been looking at your Kflop system for several weeks and this latest addition looks to be very nice addition. Does the Kstep board contain any over-current or short-circuit protection?

Thanks,
Robert

[Fish4Fun]

This is a very sweet driver! (Tom let me buy one a few weeks ago) It is like a G540 on steroids (for less money)! If you order one, I should mention one small caveat, like the G540, there is an "Enable" input that must be set "High" in order for the KStep to function. If you are using a KFlop as the signal source the proper KFlop bit is 45, configure it as an output and set it high.

If there is any interest I will set up a KStep with Mach3 (no KFlop) and report on it, but honestly it should be a very easy set up. I see no reason the KStep shouldn't meet the needs of even the most demanding NEMA23 systems and many NEMA34 systems.

Good Luck TOM!

Fish

[TomKerekes]

Does the Kstep board contain any over-current or short-circuit protection?

Besides the normal current regulation setting no it doesn't. Miss wiring the motor or power supply is likely to cause damage.

KSTEP does have over-voltage clamping and protection which we feel is a common failure mode in other drives. It also has under-voltage lockout.

Regards

[RTP_Burnsville]

Besides the normal current regulation setting no it doesn't. Miss wiring the motor or power supply is likely to cause damage.

KSTEP does have over-voltage clamping and protection which we feel is a common failure mode in other drives. It also has under-voltage lockout.

Regards

Thanks guys..... This is the info I was looking for.

Robert

[timber_MG]

Now for the big question: Does this drive have midband resonance compensation?

[TomKerekes]

Well KSTEP does seem to have excellent mid band characteristics due to the mixed decay current feedback and control. We have had all favorable reports while being compared to high end drives. KSTEP is not intended to be the “Best Money Can Buy”. It is designed to be at the sweet spot of price, performance, efficiency, resolution, and ease of use.

Regards

[John Coloccia]

I'm on the fence between KStep and Gecko, actually though I've decided on KFlop. One thing that I'm wondering is that I'm looking at 3.5A motors, but it looks like I have to either over or under drive these motors with KStep. I'm assuming that the current limit jumpers are just selecting sense resistors. Does that mean that I could solder an additional sense resistor to a jumper and get a 3.5A current limit?

I also don't see an idle reduction, but I'm assuming that it would be very simple to add one by PWMing the enables when motion isn't detected for a certain amount of time. Is that right?

I'm not a'scairt of no short circuit protection, though

I'm brand new to CNC, though I do have a background in automation. I'm intending to use this in my instrument building business.

Thanks for any help....and hello, BTW

edit: one more question too
If midrange resonance ends up being a problem in my particular setup, I wonder if anyone has developed a filter for KFlop to suppress it.
Thanks again for any info you might offer. Seems like KStep is very well thought out.

-John

[TomKerekes]

Hi John,

I wouldn't recommend soldering current resistors onto the board. I doubt if you will notice much torque reduction at the 3.13A setting especially at higher speeds where current would reduce below 3.13A anyway.

We don't have a current reduction option and PWMing the Enable doesn't work well. We intended to do this but didn't realize that the opto coupler that we selected for the Enable it too slow to PWM at a high rate. It is possible but results in an annoying audible noise. I've never been a big fan of idle current reduction. Sudden startup moves can stall coming out of idle on some systems. And your system needs to be designed to handle full on operation to run long jobs anyway.

If you add encoders for closed loop control you can observe and compensate for resonances in your system.

Regards

[John Coloccia]

Hi John,

I wouldn't recommend soldering current resistors onto the board. I doubt if you will notice much torque reduction at the 3.13A setting especially at higher speeds where current would reduce below 3.13A anyway.

We don't have a current reduction option and PWMing the Enable doesn't work well. We intended to do this but didn't realize that the opto coupler that we selected for the Enable it too slow to PWM at a high rate. It is possible but results in an annoying audible noise. I've never been a big fan of idle current reduction. Sudden startup moves can stall coming out of idle on some systems. And your system needs to be designed to handle full on operation to run long jobs anyway.

If you add encoders for closed loop control you can observe and compensate for resonances in your system.

Regards

Thanks, Tom. I may end up going with larger motors anyway and it won't me an issue. I am curious about the midrange resonance issue, though. I really don't want to go encoders at this time. I'm just wondering now that it's been out a while if this has cropped up at all?

[TomKerekes]

Hi John,

We haven't heard of any problems.

Regards

[John Coloccia]

Thanks so much for the response, Tom. I think I've decided to go with the KFlop/KStep combo. I'm a newbie here so I also need some guidance on selecting motors and power supplies. I'm going to start a separate thread for that, though.

[John Coloccia]

edit: doesn't make sense now that the robo troll's gone