Hypertherm V9 Series Phoenix Rev.11 - Manual (Page 68)

68 Phoenix 9.76.0 Installation and Setup Manual 806410
2 – Machine Setup
For most velocity loop drives, this parameter will be set to zero (0).
Feedforward Gain: Feedforward Gain can be used to drive the following error to zero during machine motion. In all
digital control loops there is a finite amount of error that is introduced by the velocity command.
Increasing Feedforward Gain can reduce this introduced error.
Velocity Gain: When using a current loop amplifier, the internal velocity loop in the CNC can be used to provide
dampening without an external tachometer.
Using the internal velocity loop with a current loop amplifier can result in higher static stiffness, smoother
machine motion, and less overshoot.
Servo Error Tolerance: Servo error, also called following error, is the difference between the commanded motor
position and the actual motor position. The servo error tolerance is the upper limit of the amount of following
error allowed before the CNC faults.
The amount of servo error tolerance depends on the cutting system mechanics. Setting the servo error
tolerance too low could cause the CNC to fault repeatedly. Setting it too high could cause inaccurate
motion or mechanical harm. Set the Following Error parameter in the Watch window and observe
steady-state operation of the cutting system (some following error is normal). Set the servo error tolerance to
a value slightly higher than the steady-state following error.
Encoder Counts per rev: Enter a value that is the number of encoder edges per revolution of the Contour Bevel Head
axis.
It is possible to enter fractional encoder units and the CNC will keep track of these fractions automatically.
Encoder Counts per rev are equal to the resolution of the encoder multiplied by the encoder revolutions per
rev.
For example, the resolution of a 4X – 1000 line encoder counts both edges (lines) of channel A and channel
B to equal 4 counts per line time multiplied by the 1000 lines per revolution would equal 4000 counts per
revolution.
Encoder Counts/Rev = 4 Counts/Line x 1000 Lines/Rev = 4000
Drive Type: This parameter is used to tell the CNC what type of control loop to run.
If you are running an external velocity loop drive (indicated by having an integrated tachometer in the motor),
select Velocity. If you are running in torque mode (no tachometer), select Current.
DAC Polarity: This parameter allows changing of the analog output polarity to establish proper control loop feedback
without any wiring changes.
Encoder Polarity: This parameter allows changing of the encoder input polarity to establish proper counting for positive
machine motion without any wiring changes.
Encoder Decode Mode: Currently the CNC only supports 4X encoder decode mode. This has been done to increase
positional accuracy.
Follower Initially: This parameter is used to determine if the CBH axis will be On when the CNC is first powered up.
Auto Home At Power Up: Determines if the contour bevel head will automatically go into the homing routine upon
powering up the CNC.