Thermal Dynamics PakMaster 75XL Plus, Operating Manual

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Manual 0-2746 3-11 INSTALLATION
A-02971
+
_
Meter set to
VAC setting
Machine
Earth Ground
Neutral
Line (Hot)
100W
Light Bulb
115 or 230VAC
WARNING
Use extreme caution. This
test uses live voltage.
115VAC: 3.0 VAC
230VAC: 1.5 VAC
V
~
V
~
VR COM A
Figure 3-17 Ground Testing
2. Increasing the ground rod length beyond 20 - 30 ft
(6.1 – 9.1 m) does not generally increase the effective-
ness of the ground rod. A larger diameter rod which
has more surface area may help. Sometimes keeping
the soil around the ground rod moist by continuously
running a small amount of water into it will work.
Adding salt to the soil by soaking it in salt water may
also reduce its resistance. When these methods are
used, periodic checking of the ground resistance is re-
quired to make sure the ground is still good.
D. Routing Of Torch Leads
1. To minimize RF interference, position torch leads as
far as possible from any CNC components, drive mo-
tors, control cables, or primary power lines. If cables
have to pass over torch leads, do so at an angle. Do
not run the plasma control or other control cables in
parallel with the torch leads in power tracts.
2. Keep torch leads clean. Dirt and metal particles bleed
off energy, which causes difficult starting and in-
creased chance of RF interference.
3.11 Tip Saver / Drag Cut Sensing
Circuit
This power supply is equipped with a Tip Saver / Drag
Cut Sensing Circuit which cuts current back to 35 amps if
the tip touches the workpiece. The purpose of this is to
prolong the life of the tip. Tip life will be considerably
shortened if tip is repeatedly touched to the workpiece
without the Tip Saver / Drag Sensing Circuit feature ac-
tive.
If the user does not want the current to be decreasedwhen
the tip touches the workpiece, the sensing circuit can be
defeated by closing switch SW1 - 1 on the Gate / Logic
PC Board. Slide top white toggle on SW1 - 1 to the right
to close circuit.
A-02569
Gate/Logic PC Board
SW1
1 2
ON
Figure 3-18 SW1 Switch Location