kmonroe023 Posted January 28, 2011 Posted January 28, 2011 I have 4 channel Acc24E2A card that we basically want to use as an analog output card. PowerPmac has assigned motor numbers to the 4 channels by default, but none are enabled (motor[x].servocntl=0). I found that if I write directly to a Dac on a particular channel, a voltage proportional to the value written will be output to the appropriate phase output (A or B). Which is good, that's what I want. But I'm wondering...is it really that simple or am I missing something that could bite me long term. If I leave the motor un-activated, is really as simple as writing values to the Dac[0] or Dac[1] term to use the outputs on the card as analog outputs? Thanks, kmonroe
Sina.Sattari Posted January 28, 2011 Posted January 28, 2011 Kmonroe, Using the DACs as general purpose analog output is as easy as you mentioned. However, in order to prevent confusion in the future in case of activating the motors, I recommend setting the Motor[x].pDac=Sys.pushm . This will prevent motors from writing to DACs in case of activation. Regards,
mhicks45884 Posted November 27, 2015 Posted November 27, 2015 Kmonroe, Using the DACs as general purpose analog output is as easy as you mentioned. However, in order to prevent confusion in the future in case of activating the motors, I recommend setting the Motor[x].pDac=Sys.pushm . This will prevent motors from writing to DACs in case of activation. Regards, I have an axis that is being used as an analog output. It is used to operate a pneumatic servo 0-10VDC. At rest the channel outputs .950VDC. Is there an I-Variable that I can adjust to get the value to Zero? I am trying to upgrade the servo valve and the new valve is much more sensitive where .950VDC actuates the valve where it did not on the old style valve. Can you help me figure a way to lower my output value?
Omron Forums Support Posted November 30, 2015 Posted November 30, 2015 You can use Motor[x].DacBias for this purpose.
mhicks45884 Posted December 4, 2015 Posted December 4, 2015 You can use Motor[x].DacBias for this purpose. Is there a specific I Value for that DacBias That I can adjust?
mhicks45884 Posted December 7, 2015 Posted December 7, 2015 I value? What do you mean? Like motor 5 gain (I believe) would be I530 using PMAC Executive. I529 would be the DAC Offset. I guess I Variable would be the better definition.
Omron Forums Support Posted December 7, 2015 Posted December 7, 2015 Power PMAC does not use I-Variables inherently in its design. "Some" I-Variable numbers are supported for legacy reasons, but it's better to move on from them and stick with the structure names. DacBias would correlate to Ixx29.
mhicks45884 Posted December 7, 2015 Posted December 7, 2015 Will PMAC Executive allow those to be entered in that format? I have found that my NEW servo valve (Proportion-Air QB1TFEE080) works well with no air. 0.085VDC with command OFF and 2.935 VDC with command ON. When I turn air ON, and the command is OFF the cutter lowers and there is 1.250 VDC to the valve. I think it is the resistance of the servo coil that is biting me. The original valve I was using is an SMC VY1100-102-FGN The overall resistance in the valves 3 wires is extremely different. That is why I would like to try to adjust the offset for that axis. Hope I am explaining it well enough for you to help me.
Jay Lee Posted December 7, 2015 Posted December 7, 2015 Power PMAC use IDE instead of Executive for interface. PMAC Executive is for Turbo PMAC, and does not allow structures. Turbo PMAC use I-variables only, and if it's Turbo, then Ixx29 is the variable you need to adjust Will PMAC Executive allow those to be entered in that format? I have found that my NEW servo valve (Proportion-Air QB1TFEE080) works well with no air. 0.085VDC with command OFF and 2.935 VDC with command ON. When I turn air ON, and the command is OFF the cutter lowers and there is 1.250 VDC to the valve. I think it is the resistance of the servo coil that is biting me. The original valve I was using is an SMC VY1100-102-FGN The overall resistance in the valves 3 wires is extremely different. That is why I would like to try to adjust the offset for that axis. Hope I am explaining it well enough for you to help me.
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