---In DynoMotion@yahoogroups.com, <dynomotion@yahoogroups.com> wrote:

Hi Eric,

I don't really understand your question or problem. PWM output should not cause an estop or reset problem.

Do you have noise on your estop input?

Regards

TK

Group: DynoMotion	Message: 8562	From: stigoestvang	Date: 11/2/2013
Subject: Re: Spindle PWM noise problem kicking my butt

Would it be possible to connect a suitably sized capacitor between the PWM pin and Ground? Value would depend of the frequency of the PWM signal. Could try with a 100nF cap for a starter. ---In DynoMotion@yahoogroups.com, <dynomotion@yahoogroups.com> wrote: Hi Tom, I don't think the problem is noise on the eStop.   The way this mill is setup is it has a BOB that the parallel port plugs into.  It also takes in all the other I/O.  It has wires going to a brushless motor control board, PWM, GND, F/R, +5.  The BOB doesn't go into a normal operational state when this happens.  I have to physically press a small reset button on the BOB to get it operational again. What I did was disconnect the wire at the KFlop that outputs the PWM, but left everything else hooked up.  I left it that way all night long.  This morning, all was still well.  I hooked the PWM wire up without a PWM signal going out, after two minutes the stock BOB went into its reset state.  The BOB has LED's on it showing the outputs and inputs.  They all go dark and I have to push the BOB's reset button to get it going again.  I scoped the PWM output of both the KFlop and the SmoothStepper.  I have them looking identical offline.  The only difference is when I plug them in and scope the signals at the brushless motor control board, the KFlop signal has some very high frequency spikes on the signal, They are so high frequency, they barely show up on my older CRT scope.  Eric ---In DynoMotion@yahoogroups.com, <dynomotion@yahoogroups.com> wrote: Hi Eric, I don't really understand your question or problem. PWM output should not cause an estop or reset problem. Do you have noise on your estop input? Regards TK Group: DynoMotion Message: 8563 From: Tom Kerekes Date: 11/2/2013 Subject: Re: Spindle PWM noise problem kicking my butt Hi Eric, Do you have information on the BOB??  What causes it to go into the mode where it has to be reset? You might try leaving the PWM signal connected but turning off the brushless motor power supply.  If there is no problem then probably noise from the brushless motor/drive is the source of the problem.  Also check if the spikes on the BOB go away when the motor power is turned off. As mentioned a Capacitor on the PWM near the BOB might remove the spikes.  I'm guessing the PWM signal goes through the BOB?  What is the frequency of the PWM? Regards TK Group: DynoMotion Message: 8566 From: az9633@ymail.com Date: 11/4/2013 Subject: Re: Spindle PWM noise problem kicking my butt The quick answer I think is to optically isolate the PWM with a high frequency opto coupler. But implementing this will require a separate power supply for the output of the opto.  I suspect that you may have a ground loop that closes when you connect the PWM signal wire.  You may have multiple power supplies and their grounds along with other signal sources coming together at the BOB.  Check what happens when you disconnect the USB between the PC and the Kflop.  If the problem goes away all you may need to do is use a USB isolator.   Is there any way you can pull 5 v and 0v from the BOB to power the Kflop?  If there isn't a 5 v source on the BOB you may need to connect the K flop power supply common DIRECTLY the BOB common then from the BOB to the Kflop.  Do not assume that if all the power supplies are connected to a ground that all is OK.  Ground wires have resistance inductance and capacitance though they are small values  high frequency noises can be generated by "tank" circuits created by these characteristics.  It is important that you also have all you Kflop I/O referenced to the same source as the BOB or optically isolate the I/O. Good Luck with this AZ   ---In DynoMotion@yahoogroups.com, <dynomotion@yahoogroups.com> wrote: Would it be possible to connect a suitably sized capacitor between the PWM pin and Ground? Value would depend of the frequency of the PWM signal. Could try with a 100nF cap for a starter. ---In DynoMotion@yahoogroups.com, <dynomotion@yahoogroups.com> wrote: Hi Tom, I don't think the problem is noise on the eStop.   The way this mill is setup is it has a BOB that the parallel port plugs into.  It also takes in all the other I/O.  It has wires going to a brushless motor control board, PWM, GND, F/R, +5.  The BOB doesn't go into a normal operational state when this happens.  I have to physically press a small reset button on the BOB to get it operational again. What I did was disconnect the wire at the KFlop that outputs the PWM, but left everything else hooked up.  I left it that way all night long.  This morning, all was still well.  I hooked the PWM wire up without a PWM signal going out, after two minutes the stock BOB went into its reset state.  The BOB has LED's on it showing the outputs and inputs.  They all go dark and I have to push the BOB's reset button to get it going again.  I scoped the PWM output of both the KFlop and the SmoothStepper.  I have them looking identical offline.  The only difference is when I plug them in and scope the signals at the brushless motor control board, the KFlop signal has some very high frequency spikes on the signal, They are so high frequency, they barely show up on my older CRT scope.  Eric ---In DynoMotion@yahoogroups.com, <dynomotion@yahoogroups.com> wrote: Hi Eric, I don't really understand your question or problem. PWM output should not cause an estop or reset problem. Do you have noise on your estop input? Regards TK Group: DynoMotion Message: 8598 From: eric_kato_sanders Date: 11/10/2013 Subject: Re: Spindle PWM noise problem kicking my butt For future thread searchers, I wanted to post my solution.  It turns out that my charge pump frequency was too low.  I was pulsing it at 1Khz 50% duty cycle.  What it likes is 12.5Khz. Eric ---In dynomotion@yahoogroups.com, <az@...> wrote: The quick answer I think is to optically isolate the PWM with a high frequency opto coupler. But implementing this will require a separate power supply for the output of the opto.  I suspect that you may have a ground loop that closes when you connect the PWM signal wire.  You may have multiple power supplies and their grounds along with other signal sources coming together at the BOB.  Check what happens when you disconnect the USB between the PC and the Kflop.  If the problem goes away all you may need to do is use a USB isolator.   Is there any way you can pull 5 v and 0v from the BOB to power the Kflop?  If there isn't a 5 v source on the BOB you may need to connect the K flop power supply common DIRECTLY the BOB common then from the BOB to the Kflop.  Do not assume that if all the power supplies are connected to a ground that all is OK.  Ground wires have resistance inductance and capacitance though they are small values  high frequency noises can be generated by "tank" circuits created by these characteristics.  It is important that you also have all you Kflop I/O referenced to the same source as the BOB or optically isolate the I/O. Good Luck with this AZ   ---In DynoMotion@yahoogroups.com, <dynomotion@yahoogroups.com> wrote: Would it be possible to connect a suitably sized capacitor between the PWM pin and Ground? Value would depend of the frequency of the PWM signal. Could try with a 100nF cap for a starter. ---In DynoMotion@yahoogroups.com, <dynomotion@yahoogroups.com> wrote: Hi Tom, I don't think the problem is noise on the eStop.   The way this mill is setup is it has a BOB that the parallel port plugs into.  It also takes in all the other I/O.  It has wires going to a brushless motor control board, PWM, GND, F/R, +5.  The BOB doesn't go into a normal operational state when this happens.  I have to physically press a small reset button on the BOB to get it operational again. What I did was disconnect the wire at the KFlop that outputs the PWM, but left everything else hooked up.  I left it that way all night long.  This morning, all was still well.  I hooked the PWM wire up without a PWM signal going out, after two minutes the stock BOB went into its reset state.  The BOB has LED's on it showing the outputs and inputs.  They all go dark and I have to push the BOB's reset button to get it going again.  I scoped the PWM output of both the KFlop and the SmoothStepper.  I have them looking identical offline.  The only difference is when I plug them in and scope the signals at the brushless motor control board, the KFlop signal has some very high frequency spikes on the signal, They are so high frequency, they barely show up on my older CRT scope.  Eric ---In DynoMotion@yahoogroups.com, <dynomotion@yahoogroups.com> wrote: Hi Eric, I don't really understand your question or problem. PWM output should not cause an estop or reset problem. Do you have noise on your estop input? Regards TK Group: DynoMotion Message: 8639 From: az@aimele.com Date: 11/14/2013 Subject: Re: Spindle PWM noise problem kicking my butt What charge pump? Is it on the Novakon BOB? az Group: DynoMotion Message: 8642 From: eric_kato_sanders Date: 11/14/2013 Subject: Re: Spindle PWM noise problem kicking my butt  Yes, it is on the Novakon BOB. ---In dynomotion@yahoogroups.com, <eric@...> wrote: I am trying to move from Mach3/Smooth Stepper to KFlop.  All is working, but as mentioned in a previous post, the stock breakout board on my Novakon mill goes into reset mode after a couple of minutes if I even have the PWM wire attached to the board much less running.  I put it on the scope and found that the square wave, although nicely shaped, did have high frequency random noise.  I tied everything to ground that I could find, but I still have the noise.  What is odd is the Smooth Stepper doesn't display the noise on the spindle PWM.  Anything else I can try? Group: DynoMotion Message: 8646 From: ericncn Date: 11/14/2013 Subject: Re: Spindle PWM noise problem kicking my butt Pardon me for the OT but I'm curios about the Novakon. I was very interested in Novakon (price looked very good for its specifications) but then I read terrible comments on various forums, that discouraged me to buy. So, have you actually bought one? Did you experience any problem with payment, delay with delivery, etc? I understand that you want to replace the electronics but are you happy at least with the mechanical part? I am now suspecting those bad comments may have been maliciously spread by competitors... by reading the comments it looked like it was a scam and you couln't actually get one Thank you EC ---In DynoMotion@yahoogroups.com, <az@...> wrote: What charge pump? Is it on the Novakon BOB? az Group: DynoMotion Message: 8649 From: eric_kato_sanders Date: 11/15/2013 Subject: Re: Spindle PWM noise problem kicking my butt  Hi Eric, I was in the same boat as well.  There was one site that really trashed them so I didn't even consider them.  A year later, they had a clearance sale on their NM-145 mills to make room for their next generation.  The price was low enough to encourage me to research them a little more.  I found posts that described the other side of the story.  Novakon had a bad run of brushless drives from the manufacturer that caused a lot of heart ache.  I've had no problems what so ever.  They have always been real good to respond to any questions.  I'm not replacing any of their electronics, just integrating the KFlop as my controller rather than Mach3 and the Smooth Stepper. Eric ---In DynoMotion@yahoogroups.com, <ericnc@...> wrote: Pardon me for the OT but I'm curios about the Novakon. I was very interested in Novakon (price looked very good for its specifications) but then I read terrible comments on various forums, that discouraged me to buy. So, have you actually bought one? Did you experience any problem with payment, delay with delivery, etc? I understand that you want to replace the electronics but are you happy at least with the mechanical part? I am now suspecting those bad comments may have been maliciously spread by competitors... by reading the comments it looked like it was a scam and you couln't actually get one Thank you EC ---In DynoMotion@yahoogroups.com, <az@...> wrote: What charge pump? Is it on the Novakon BOB? az