Hypertherm PHC Sensor - Manual (Page 46)

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Sensor™ PHC Operation and Setup Guide
Automatic Operation
Automatic voltage control operation is selected by placing the lower center toggle switch in the upper auto
position. In this mode, the unit automatically performs IHS to the set pierce height, ignite the plasma torch, wait
for the torch to pierce the plate, and begin the cutting machine motion.
The basic Sensor™ PHC auto operation setup consists of three steps:
1. Set arc voltage
Use the larger multi-turn adjustment, to set the arc voltage on the display. The starting point for this
voltage should be included in the cut charts supplied with your plasma system. It is important to remember
that this voltage is just a starting point since the actual arc voltage depends on consumable wear, torch
lead lengths, gas flow rates, and machine motion. For optimal cut quality you must make small
adjustments to the nominal arc voltage that is specified in the cut charts. The important item to control is
the torch-tip to work height during a cut. The arc voltage is just an indirect method to control this height.
2. Set IHS retract or pierce height
Use the lower left rotary control to set the IHS retract height. As this control is adjusted, the display is
temporarily overridden with a 0 to 10 reference level. This represents the desired pierce height. The actual
height should be available in the cut charts supplied with the plasma system. This setting is approximate
because it depends on whether the unit can sense the plate using ohmic contact or must rely on the
backup limited force stall sensing.
Check this setting by performing an IHS test and check for the correct pierce height. Each time the lower
left IHS test switch is pressed, the torch alternates between the set IHS height and the end of cut retract
height. Continue testing and fine tuning this adjustment until the desired IHS height is achieved.
If the IHS speed (DIP SW #5) has been set to the normal low speed setting, then the IHS retract
adjustment range should be between about 50 thousandths and 1/2 inch. If the IHS speed was set to the
high speed setting, then the IHS retract adjustment range should be between about 1/10
th
inch and 1 inch.
3. Set pierce delay time
Use the lower right rotary control to set the pierce time delay. As this control is adjusted, the display is
temporarily overridden with a 0 to 4.0 second delay time. This is the time delay between igniting the torch
and beginning the cut motion. The pierce delay is the time required for the plasma torch to initially cut
through the plate. This time delay should be included in the cut charts provided with your plasma system.
To provide more accuracy for the short delay settings, this rotary control is divided into two ranges. The
first range covers the first ½ rotation of the control and provides a linear delay between 0 and 1 second.
The second ½ rotation provides a linear delay of between 1 and 4 seconds.