Thermal Dynamics A40i, Operating Manual

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A40i, A60i
Manual 0-5466 INTRODUCTION
2T-3
A-08331
Workpiece
Power
Supply
+
_
C
B
A
Typical Torch Head Detail
By forcing the plasma gas and electric arc through a
small orifice, the torch delivers a high concentration
of heat to a small area. The stiff, constricted plasma
arc is shown in Zone C. Direct current (DC) straight
polarity is used for plasma cutting, as shown in the
illustration.
Zone A channels a secondary gas that cools the torch.
This gas also assists the high velocity plasma gas in
blowing the molten metal out of the cut allowing for
a fast, slag - free cut.
B. Gas Distribution
The single gas used is internally split into plasma
and secondary gases.
The plasma gas flows into the torch through the
negative lead, through the starter cartridge, around
the electrode, and out through the tip orifice.
The secondary gas flows down around the outside
of the torch starter cartridge, and out between the
tip and shield cup around the plasma arc.
C. Pilot Arc
When the torch is started a pilot arc is established
between the electrode and cutting or gouging tip.
This pilot arc creates a path for the main arc to
transfer to the work.
D. Main Cutting Arc
DC power is also used for the main cutting arc. The
negative output is connected to the torch electrode
through the torch lead. The positive output is con-
nected to the workpiece via the work cable and to
the torch through a pilot wire.
E. Parts - In - Place (PIP)
The torch includes a 'Parts - In - Place' (PIP) circuit.
When the shield cup is properly installed, it closes
a switch. The torch will not operate if this switch
is open.
PIP Switch
Shield Cup To ATC
CNC Start
PIP Switch
Shield Cup
PIP Switch
Shield Cup
Remote Pendant
Automation Torch
To ATC
To ATC
Art # A-08168
Parts - In - Place Circuit Diagram for Machine Torch
A-02997
Torch Trigger
PIP Switch
Shield Cup
To Control
Cable Wiring
Torch Switch
Parts - In - Place Circuit Diagram for Hand Torch