Tweco 150XL CE PAK Master - Manuel (Page 35)

Manual 0-2826 4-7 OPERATION
4.06 System Operation
NOTE
Frequently review the safety precautions at the front
of this manual.
This section contains operating information which is spe-
cific to the power supply. Detailed operating informa-
tion for torches can be found in the appropriate Torch
Instruction Manual.
WARNINGS
Disconnect primary power at the source before as-
sembling or disassembling power supply, torch
parts, or torch and leads assemblies, or adding cool-
ant.
It is not enough to simply move the ON/OFF switch
on the unit to OFF position when cutting opera-
tions have been completed. Always open the power
supply disconnect switch five minutes after the last
cut is made.
A. Operational Suggestions
The suggestions below should be followed in all cutting
and gouging operations:
1. Wait five minutes before setting the ON/OFF switch
to OFF after operation. This allows the cooling fan to
run to dissipate operating heat from the power sup-
ply.
2. For maximum parts life, do not operate the pilot arc
any longer than necessary.
3. Use care in handling torch leads and protect them from
damage.
4. In continuous cutting applications using CO2, it is of-
ten necessary to manifold four to six cylinders together
to maintain adequate flow at operating pressures.
B. Fold Back Feature
Should the torch tip contact the workpiece or molten
slag, the output current will immediately drop to 35
amps to minimize potential tip damage.
4.07 Optional Power Supply
Settings
The following functions can be used to tailor a system for
special application requirements or unique user prefer-
ences. These functions are controlled by DIP switches
located on the Logic Control PC board in the power sup-
ply.
Remove the left side panel and locate the Logic Control PC
Board near to top center of the unit. Set the function as
required.
A. High/Low Speed Auto-Restart Function
(SW5)
The Plasma Power Supply is always in the Auto-Restart
mode. This means that at the end of the cut, if the START
signal is still on, the pilot will restart automatically.
An immediate pilot restart, when cutting over holes or
expanded metal at relatively slow speeds, may cause the
arc to transfer back to the piece just cut. This happens
because the torch has not had time to be moved away
from the cut piece and results in extra starts and unnec-
essary parts wear.
The High/Low Speed Auto-Restart switch, SW5, has two
settings as follows:
• Low Speed - adds a one-tenth second delay to the
pilot restart to prevent arc back conditions.
• High Speed - no delay required as it may delay
starting on the next edge.
A-02258
Logic PC Board
SW5
1 2
Figure 4-6 High/Low Speed Auto-Restart Switch
SW5 Location