Jump to content
OMRON Forums

How can PMAC know that what a speed 1V means?


KiraYamato
 Share

Recommended Posts

Hello, everyone, here I come again~

 

I am using Turbo Pmac2 Clipper to control Fuji Servo systems,

 

and I set it to work in the analog mode.

 

So the PMAC gives out an analog voltage command which present a rotation velocity

 

but you see that the command in a motion program has the unit of counts/msec,

 

So how can PMAC know that what a speed 1V means?

 

Or How can PMAC know that what a voltage should output when receive a speed command in the unit of cts per second?

 

thank you for your attention~

Link to comment
Share on other sites

  • Replies 7
  • Created
  • Last Reply

Top Posters In This Topic

Popular Days

Top Posters In This Topic

PMAC doesn't know and doesn't care about the relationship of volts to speed(or torque). It will adjust the analog signal to match the commanded position. All scaling of what the analog signal means is done in the drive. PMAC is blind to the scaling, and whether the drive is in torque or velocity mode.
Link to comment
Share on other sites

BUT, DO N'T YOU THINK THAT IT WILL RESULT A LONG DYNAMIC PROCESS AND A BAD RESULT FOR A TRAJACTORY FOLLOWING?

 

Hello, everyone, here I come again~

 

I am using Turbo Pmac2 Clipper to control Fuji Servo systems,

 

and I set it to work in the analog mode.

 

So the PMAC gives out an analog voltage command which present a rotation velocity

 

but you see that the command in a motion program has the unit of counts/msec,

 

So how can PMAC know that what a speed 1V means?

 

Or How can PMAC know that what a voltage should output when receive a speed command in the unit of cts per second?

 

thank you for your attention~

 

PMAC doesn't know and doesn't care about the relationship of volts to speed(or torque). It will adjust the analog signal to match the commanded position. All scaling of what the analog signal means is done in the drive. PMAC is blind to the scaling, and whether the drive is in torque or velocity mode.

 

 

Link to comment
Share on other sites

Thank you for your explanation. By the way,my Turbo PMAC works in PWM mode, it give the amplifier a analog voltage signal as a velocity command, so PMAC also look at counts only?

 

That is correct. If you use the motor in a coordinate system, then you can scale counts to real world units, but as far a PMAC is concerned, it only looks at counts.

 

 

Link to comment
Share on other sites

The Clipper has can work in direct PWM mode, but your amplifier has to be compatible. It sounds like your amplifier is traditional analog. The Clipper doesn't have true DACs, but produces a PWM signal that looks like an analog signal to most amps. Be sure to set your frequencies correctly(in the manual), or your motor will jitter and overheat.
Link to comment
Share on other sites

Guest
This topic is now closed to further replies.
 Share


×
×
  • Create New...