Messages

181

General Mach Discussion / Re: Digispeed not working

« on: March 29, 2012, 05:02:11 AM »

You need to go to the motor config tab and set the spindle step to Active low

182

General Mach Discussion / Re: Digispeed not working

« on: March 28, 2012, 07:31:41 PM »

The way I do my testing is this.

1. Connect a dc power supply in the range if 6v to 15V in place of the supply coming from the VFD.

2. Initially set the max spindle speed to the supply voltage times 100. so if you are using a 9V battery set it to 900

3. Now in Mach3 enable the spindle and set the speed to the maximum spindle setting. In out case 900

4. Ensure that the DC-03 multi-turn attenuation potentiometer is turned fully clockwise. (Max output, no attenuation)

5. Measure the voltage being generated by the Digispeed. It will be less than 9V by about 0.7V as this is "stolen by the semiconductor junctions.

6. Then set the Max pulley setting to match this measured voltage level, say 830. This would equate to 8.3V

7.  Now, you can check the linearity of the generated voltage against the commanded voltage. If you want to see 5.4V at the output , enter a speed of 540rpm. You can then check a range of values.


Then, once you hook it up to the VFD set the Max pulley speed  to match the actual measured maximum speed. Note that if you supply 10V from the VFD to the DigiSpeed, you won't get 10V back, but a little less. This will consequently reduce the maximum speed of you spindle. If this is a problem, you have two options;
1. Some VFDs have parameter settings that allow you to scale the max speed of the spindle. That is, you can set up the VFD to produce 400Hz (max speed) when it sees 9.3V rather than 10V at the control voltage input.
2. Use an on-board  DC/DC converter in the DC-03. With this the DC-03 will not rely on the 10V supply from the VFD, but generate the voltage it self.

Cheers,

Peter.
 

183

General Mach Discussion / Re: Digispeed not working

« on: March 28, 2012, 08:05:04 AM »

Katoh,

Good to see you are making progress.

To test the analog voltage output without using a VFD, just use a 12V dc supply, or even a 9V battery connected to AV+ and Agnd in place of the VFD. You can then use a multimeter to measure the output voltage between Aout and Agnd.

Cheers,

Peter

184

General Mach Discussion / Re: Digispeed not working

« on: March 27, 2012, 08:34:13 AM »

Hi Katoh,

Thanks for the photo. from the jumper settings you are using the charge pump enable and the enable lo input to enable the BoB. Can you confirm that the Enable  Led on the BoB is flashing about 3 times per second. Can you confirm that the enable led is flashing at this rate?

Note that if the enable jumper is removed then that particular enable input is being controlled by you. If the jumper is inserted then it is over-ridden and does not affect  the enabling of the board.

There is a problem here. Currently you have configured the board to accept a charge pump signal from Mach3 on pin 17. You then say you are using pin 17 to control one of the relays. You cannot use pin 17 for both.

While we try to get the DigiSpeed to work, put a jumper in the Lo and CP position  of JP1. This way the BoB will always be enabled. Also ensure that in Mach3, that in the config tab for Outputs you disable the chargepump output.



You have set the pullup resistors on all pins to pull them to 0V. From that, you should be setting up the output signals on these pins to use positive logic (active when 5V is applied)

You should also be setting the DC-03 to use positive logic as well. For this, JP3 should be at the end with the ^ arrow.

You should also be setting two of the Mach3 outputs signals to control the parallel port pins 14  and 17. These pins are being used to control the two DC-03 relays.

These two outputs should then be set in the Spindle config tab to be controlled by the M3 and M4 commands.

Once you have done this you should be able to turn on the relays by entering "M3" and "M4" in the MDI input line.

Cheers,

Peter.

185

General Mach Discussion / Re: Digispeed not working

« on: March 27, 2012, 01:54:42 AM »

Hi Katoh,

The leds on the breakout board help by showing you what Mach3 is doing to the parallel port lines.

If the LEDs on the BoB do not turn on or off as expected, then mach3 is not controlling the pins as expected. If that's the case, then the DC-03 will not work as expected either.

Can you take a photo of the MB-02V6 Bob and the DC-03V3 so I can see what jumper settings you have?

Cheers,

Peter.

186

General Mach Discussion / Re: Digispeed not working

« on: March 25, 2012, 10:07:12 PM »

optco
I reckon its just something we are overlooking with the MB02V6 boards, as I can get, and have got the darn things running with the other boards, as you well know.


Peter,
Should have added on earlier post Pin 16 is connect to Sig on the DC03 and Pin 8 is to RL1 pin 9 to RL2.
5v and 0v come from the BOB as per drawings and the BOB has its own seperate 5v power supply.
Cheers
Katoh

Spent the weekend doing kids sport.  OK a couple of things.

In  EN012V3, the MB-02 is set up for positive logic on outputs 1,14,16,17(JP4)  and negative logic on pins 2-9 (JP7).
In  EN012V3, the DC-03 is set up for positive logic (JP2)

Since you are driving the two relays from pins 8 and 9 which are set up for negative logic, I'd suggest using negative logic for the DC-03 as well. So,
1. On the MB-02 change  the jumper on JP7 to  the 5V end.
2. On the DC-03 change JP2 end with the v pointing arrow.
3 on the Mach3 outputs tab, tick the active low column for output 1 and output 2.
4.on the motor outputs tab tick the active low for the spindle tab

Also in your motor outputs you have pin 1 controlled by your spindle dir output. What is pin 1 actually connected to? If it's not connected to anything then that's fine, otherwise set the port for Spindle dir to port 0 as your not using it.

Once you have set that up tellme what the DC-03 relay leds are doing?

Cheers,

Peter.

187

General Mach Discussion / Re: Digispeed not working

« on: March 22, 2012, 04:39:01 PM »

Hi,

Can you provide me with the following,
1. an image or description of the jumper settings on the DC-03
2. an image or description of the jumper settings on the MB-02
3. a screen capture of the Mach3 Motor outputs setting tab
4. a screen capture of the Mach3 Motor outputs setting tab
5. a screen capture of the Mach3 outputs setting tab
6. a screen capture of the Mach3 spindle setting tab


From that I should be able to get you on the right track.

So, is it only the relays you are struggling with, or do you also have problems with the Speed control as well?

Cheers,

Peter

188

General Mach Discussion / Re: Digispeed not working

« on: March 20, 2012, 09:31:11 PM »

Hi peter
Sorry for the late response, I see on the updated schematic there is no Reverse wire to the VFD. How will the M3 and M4 work?
Thanks
Katoh

Katoh,

Do you need to use reverse is the first question?

The parallel port has 12 outputs and 5 inputs so yyou need to engineer your system to work within these limitations (or use a 2nd parallel port).

EN012 http://www.homanndesigns.com/pdfs/EN012_V3.pdf is setup for 4 axes. If you are only using 3, then you can also use pins 8 and 9 for other things.

Also in the Engineering note I've set the breakout board to use pin 17 for the charge pump enable. If you did not need that, you could then also free up pin 17 for other use.

As to the DigiSpeed, it needs an output pin to control each relay. If you don't need to use both relays, then don't.

To control the relays via the spindle M3 and M4 codes (assuming you want to have reverse) you can do it as below.

1. First choose the output pins that will be use to control the relays. If you only have a 3 axis machine it could be say pins 8 and 9.
2. Wire up the DC-03, connecting say relay 1 to pin 8 on the MB-02V6
3. Wire up the DC-03, connecting say relay 2 to pin 9 on the MB-02V6
4. In the Mach3 outputs config tab, assign pins 8 and 9 to be controlled by Mach3 outputs, say Output5 for pin 8 and Output 6 for pin 9
5. In the Mach3 spindle config tab, assign M3 to turn on Output5 (Pin 8 thus relay 1)
6. In the Mach3 spindle config tab, assign M4 to turn on Output6 (Pin 9 thus relay 2)

So now, when you use M3, Relay 1 will turn on. If you use M4 relay 2 will turn on.


If you Motor controller needs a direction input and an Enable input, then the config is different. Assuming we are using Relay 1 to switch the enable and relay 2 to switch the direction, the setup would be;
1. First choose the output pins that will be use to control the relays. If you only have a 3 axis machine it could be say pins 8 and 9.
2. Wire up the DC-03, connecting say relay 1 to pin 8 on the MB-02V6
3. Wire up the DC-03, connecting say relay 2 to pin 9 on the MB-02V6
4. In the Mach3 outputs config tab, assign pin 8  to be controlled by Mach3 outputs, say Output5
5. In the Mach3 Motor config tab, assign pin 9 to be the spindle axis dir pin on port 1
6. In the Mach3 spindle config tab, assign M3 to turn on Output5 (Pin 8 thus relay 1)
7. In the Mach3 spindle config tab, assign M4 to turn on Output5 (Pin 8 thus relay 1)

Notice a couple of things here. M3 or M4 will turn on Relay 1. We need this as Relay 1 is the Enable so must be active in FWD and REV.
Relay 2 is now controlled by the Spindle axis direction output. Mach3 will automatically set this pin when a M3 or M4 is issued.

Note: In PWM mode, the Spindle axis Step pin is set to the pin that will carry the  PWM signal to the DC-03V3.

Hopefully the above is clear enough to understand.

Cheers,

Peter.

189

General Mach Discussion / Re: Digispeed not working

« on: March 20, 2012, 09:03:18 PM »

Hi,

No need to set a trap. I'm here.

Ok to answer a few things.

1.Step Pulse Control DC-06 - This DigiSpeed takes a step pulse train and converts it to a control voltage, where the voltage is set by the frequency of the step pulses.   Basically the pluses are used in a charge pump. An analogy of this is filling up a bucket that has a leak using a cups of water. You can maintain any level in the bucket by varying the rate at which you fill it.

The problem is that it is difficult to control all the variables. The rate at which the charge pump leaks is controlled by components that have tolerances. Also, the rate at which the charge pump charges is controlled by the step pulse (size of cup).

Other CNC component manufactures also use this technology in the converters,. They require you to set the step pulse to a particular value to match what they need. This means that this step pulse is also then used for the stepper/servo drives and my be non-optimum.

On the DC-06 I put a monostable to ensure that the step pulse sent to the chargepump was always a constant width. This eliminated one variable. The component tolerances is a lot harder to fix. This results in the user having to play around with the steps/per value for the spindle axis to get the frequency of the step pulse correct. This means going back an forth to the axis setup screen which is a real pain.

The frequency needs to be high enough to get full scale voltage out of the DC-06, but if it is too high, the voltage will max out too early, resulting in a non-linear speed  response from the spindle motor.

I spent way too much time  supporting people setting up the DC-06. Don't get me wrong, once set up it is as good as the DC-03, but with the required support it wasn't cost effective.



2.PWM Control  DC-03 - This DigiSpeed accepts a PWM waveform from Mach3 where the Duty Cycle (mark/space ratio) represents the speed as a percentage of the spindle maximum speed. That is if the PWM duty cycle is 25% then the voltage out is 25% of the Analogue control voltage supply from the Motor controller.

Setting up is extremely easy. Measure the maximum spindle speed, then enter it into the Max pulley setting. That's about it.

The other advantage of the DC-03 is that is is more EMI resistant than the DC-06. Extra spikes on the DC-06 step line get converted in charge pump pulses that bump up the control voltage.


Relays - Both the DC-03 and DC-06 have two general purpose SPDT signal relays on board. These can be used for a variety of uses (or not at all) depending on what motor controller you are using and it's requirements.

Some Motor controllers require separate FWD and REV inputs, Some have a DIR input and an ENABLE. The two relays can usually be configured to operate as the controller requires.

Cheers,

Peter.

190

General Mach Discussion / Re: Digispeed not working

« on: March 20, 2012, 04:09:45 AM »

Hi Katoh,

The version of the engineering note you re looking at is version 1, the current version is V3. It shows a different setting as line 17 is used by the Chargepump.

http://www.homanndesigns.com/pdfs/EN012_V3.pdf

Cheers,

Peter.