Hypertherm V9 Series Phoenix Rev.11 User Manual
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Phoenix 9.76.0 Installation and Setup Manual 806410
3 – Torch Height Control Axis Setup
The following definitions provide the default or recommended value for each parameter. These values are appropriate for
the majority of applications.
Proportional Gain: The Proportional gain value determines how quickly the CNC adjusts its command to compensate
for any positional error. If proportional gain is too high, the system and axis become unstable. During cutting,
the torch can overshoot the required height. If proportional gain is too low, the system response is not
precise.
Range: > 0 to 32,000
Recommended setting: 25
Feedforward Gain: The value for feedforward gain is a multiplier that reduces following error. In all digital control loops,
the velocity command causes some following error. Increase feedforward gain to reduce this type of error.
When using stall force for workpiece sensing, feedforward gain can cause the torch to strike the workpiece
with to much force. Set feedforward gain to 0 for this and most applications.
Note: The weight of the torch assembly can also be a factor in setting the value for this gain.
Range: 0 to 32,000
Recommended setting: 0 – 30; Sensor THC: 0
Derivative Gain: Derivative gain helps to minimize and smooth out the effect of sudden changes in speed. A higher
value for derivative gain results in a slower response time to changes in speed in the control loop.
Derivative gain reduces future errors that are based on the current rate of change (acceleration or
deceleration). For example, derivative gain prevents overshooting a corner by preventing unchecked
acceleration as the torch approaches the corner.
For most velocity loop drives, this parameter is set to zero (0).
Range: 0 to 32,000
Recommended setting: 0 – 20; Sensor THC: 0
Velocity Gain: This parameter is available only if you select Current for Drive Type and you have a CNC, such as the
EDGE
®
Pro Ti, that controls both position and velocity loops. Use this parameter to tune the internal velocity
loop of the CNC to provide smoother machine motion and less overshoot.
Range: 0 to 32,000
Recommended setting: 0 for Sensor THC lifter which does not use Velocity Gain. 100 for other lifters
such as the Sensor Ti that use current drives.
Integral Gain: Integral gain improves the positioning accuracy of the torch and reduces the cumulative effect of past
errors that are caused by static friction or gravity. Excessive integral gain can result in system instability.
Range: 0 to 32,000
Recommended setting: 0; Sensor THC: 0