Lincoln Electric Growth Series, Инструкция по сборке

Страница: 72 / 94

Torchmate 2x2 Growth Series
62
AVHC
components
• The AVHC system consists of:
• A motor driven Z-axis that raises and lowers the torch under control of the Accumove2
• An ohmic cap sensor for finding the “zero height” of the torch prior to starting an arc
• A VFC electronics box that measures the arc voltage when the arc has started and
sends a signal to the Accumove2 indicating that voltage.
• An optional magnetic breakaway sensor to protect the torch from collisions with tipped
up parts
• Cables to connect the components to the Accumove2, the sensors, and the plasma
power unit
• Plasma cutters are designed to produce a constant electrical current in the plasma arc. If
the distance between the torch and the workpiece is longer, a higher voltage must be used
to maintain the current than if the distance is shorter (because of the riesistance of the air).
• Cut bevel is created when the arc length is either too long or too short or the torch travel
speed is too fast or too slow.
• The optimum arc length for a given material type, thickness, and amperage (current),
will produce the best quality. The cut charts supplied with the plasma cutter give the
preferred starting point for determining the optimum arc length.
• In the Growth Series with Accumove2 Software manual, you will find instructions for
fine tuning the cutting speed for a given arc length and amperage.
• Using sophisticated computations, the Accumove2 adjusts the speed and torch height at
various points along curves and at corners to compensate for the changes in effective arc
length that happen in those parts of the cuts, to achieve greater quality and reliability.
• Before an arc is initiated by the Accumove, the AVHC must raise the torch tip to the
recommended pierce height (typically some distance greater than the established cutting
arc length). Because of the non-uniformity of the material being cut, this pierce height is
measured by using an ohmic cap to sense the zero distance.
• To determine the position of the material, the AVHC lowers the torch until the torch cap just
touches the material. A wire connect between the VFC and the cap lets the VFC know when
the cap touches the material and completes it’s circuit.
• Following this, the Accumove2 raises the torch to the level of the initial pierce height. This
height is also found in the plasma cutter’s cut charts.
Features of the Accumove2 AVHC
The Growth Series tables with Accumove2 Technology includes an intelligent AVHC system to produce cuts
with a high quality level. Other than good quality consumables, the primary factor governing cut quality is the
length of the plasma arc. Standard arc lengths are published for each plasma cutter and the AVHC system
uses the arc voltage measuring technique to control the height of the torch above the material being cut.
What is arc
voltage?
Ohmic cap
sensing