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phyllis_ave
09-02-2009, 04:47 AM
Hi there,

I have a setup with MACH3 where it should send a PWM signal, which will be converted by a digispeed board into a 0-10V analogue signal for my motor drive, but all I am getting out of the digispeed board is 0.1V max.

I've tried adjusting the attenuation trimpot on the digispeed board but it doesn't seem to do anything

Does anyone know what could be wrong here?


Just to be make sure I am testing the right thing, if the output from the digispeed board isn't connected to anything it should still send out the analogue signal, correct? I am just plugging my multimeter directly into the output on the digispeed board and getting the 0-0.1V readings.

Thanks in advance,

Phil

jalessi
09-02-2009, 06:36 AM
What model breakout board do you have?

GaryCorlew
09-02-2009, 07:12 AM
Don't have a digispeed but with a cnc4pc board the pulse width affects the voltage output, so you may want to take a look at that. I have mine at 5

phyllis_ave
09-02-2009, 08:47 AM
jalessi: I have the C10 model board from CNC4PC.

Gary: When you say your pulse width is 5 what do you mean? Is there a setting in MACH3 to control this?

jalessi
09-02-2009, 09:06 AM
Do you have a instant messenger?

Jeff...

jalessi
09-02-2009, 09:10 AM
What model Digispeed do you have?

phyllis_ave
09-02-2009, 10:47 AM
I have the digispeed DC-03.

I have the digispeed connected just as it says in the user guide, with the 5V and GND from the breakout board and the PWM from the output pin assigned in MACH3. I'm also running the relays on the board to enable and set the direction of the spindle.

I have windows messenger - phyllis_ave@hotmail.com - but I won't be online for a while since its past midnight here and I'm about to go to bed.

phomann
09-24-2009, 03:32 AM
Hi,

I just noticed this thread. Did you sort out your issues with the DC-03?

Cheers,

Peter.

LeeWay
09-24-2009, 07:18 AM
There are lots of settings in Mach 3 that have an effect on spindle control. The manuals Peter has are pretty darn good though with screen shots. Can't get better than having Peter answer directly though. ;)

phyllis_ave
10-01-2009, 08:29 PM
Yes I am still having trouble with the DC-03, although I am pretty new at this so I've probably just overlooked something really simple.

At the moment the DC-03 shows the double flash (PWM mode) but I'm not getting the output voltage I need.

I think my problem is probably in MACH3 but I can't seem to find what I've done wrong.

Also here's my wiring setup for the DC-03 just in case I've done something really stupid here.

Ana - none
+5V - +5V from breakout board
RL2 - CCW output from BoB
RL1 - Enable from BoB
Sig - Spindle Step from BoB
Gnd - Common from BoB

AV+ - none
Vout - DC control voltage (should be +0-10V)
AGnd - DC control voltage ground
Relay outputs are connected to the switches in my motor controller

Note: The relays are working fine, its just the speed control voltage that I'm having trouble with.

phomann
10-01-2009, 09:14 PM
Yes I am still having trouble with the DC-03, although I am pretty new at this so I've probably just overlooked something really simple.

At the moment the DC-03 shows the double flash (PWM mode) but I'm not getting the output voltage I need.

I think my problem is probably in MACH3 but I can't seem to find what I've done wrong.

Also here's my wiring setup for the DC-03 just in case I've done something really stupid here.

Ana - none
+5V - +5V from breakout board
RL2 - CCW output from BoB
RL1 - Enable from BoB
Sig - Spindle Step from BoB
Gnd - Common from BoB

AV+ - none
Vout - DC control voltage (should be +0-10V)
AGnd - DC control voltage ground
Relay outputs are connected to the switches in my motor controller

Note: The relays are working fine, its just the speed control voltage that I'm having trouble with.

Hi,

First thing to do is make sure that the DC-03 is in the correct mode. There are 2 jumpers (JP3)that set the mode.

The status LED on the DC-03 indicates the mode that the DC-03 is in, when the unit is powered up.

For PWM mode, the status LED will flash twice on powerup before going into the lazy double flash. The manual explains these modes.

Also, have a look at this engineering not. It shows the position of the mode jumper for PWM mode.

http://www.homanndesigns.com/EN009_V2.pdf


The double lasy flash indicates that their is no PWM signal from Mach3 at the DC-03 'Sig' input.

The manual also has a step by step Quick Start set-up guide. If you follow it, tell me at which point you can't get it to work.

Cheers,

Peter.

phyllis_ave
10-01-2009, 09:27 PM
Ok I do get the double flash on startup then the lazy double flash after that. Also I have the JP1 jumper on the dc/dc side and I am not using the AV+ pin. Is this correct?

It seems like there is some control coming from MACH3 as the voltage does change when I change the spindle speed, however it only varies from around 0-0.1V instead of the 0-10V that I should be getting.

phomann
10-01-2009, 09:58 PM
Ok I do get the double flash on startup then the lazy double flash after that. Also I have the JP1 jumper on the dc/dc side and I am not using the AV+ pin. Is this correct?

It seems like there is some control coming from MACH3 as the voltage does change when I change the spindle speed, however it only varies from around 0-0.1V instead of the 0-10V that I should be getting.


Presumably you have the DC/DC converter installed. :)


Also JP2 selects whether you are using positive or negative pulses. You need to have this set to match what you have set up in Mach3.

If you are only seeing the lazy double flash, then the microprocessor is not seeing a PWM waveform. That is where we need to concentrate. If the micro is not seeing the PWM, it won't produce a control voltage at the output.

Cheers,

Peter.

phyllis_ave
10-01-2009, 10:03 PM
Isn't the DC/DC generator on the DC-03 board? Or is it a separate part that I don't have? Because if thats the case then I've found my problem...

Should I just use the AV+ connection and move the JP1 jumper then?

Also thanks for helping me out with this, its been driving me crazy for a while now.

phomann
10-02-2009, 12:45 AM
Isn't the DC/DC generator on the DC-03 board? Or is it a separate part that I don't have? Because if thats the case then I've found my problem...

Should I just use the AV+ connection and move the JP1 jumper then?

Also thanks for helping me out with this, its been driving me crazy for a while now.

If you have an empty 8 pin dil IC socket in the middle of the board, then you don't have the dc/dc converter installed. In that case, yes move the jumper JP1 to the AV+ position and provide the AV power from your VFD

Cheers,

Peter.

phyllis_ave
10-02-2009, 02:36 AM
Ah ok that'll do it. I knew it would be something stupid done on my part.

Thanks so much for your help Peter, you're a lifesaver.