MK Products Cobramatic Pro 150-008, Owner'S Manual

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Cobramatic ® Pro Series Owner’s Manual - Page 4
Section B
Gas Inlet
Front panel access to attach gas hose to bottom fitting of power block.
Work Cable (Ground)
Connect a work lead of sufficient size and length between the proper output
stud on the power source and the work. Be sure the connection to the work
ground makes tight metal to metal electrical contact. Improper work lead
connections can result in poor arc initiation, and unsatisfactory weld results.
Consult welding power supply manufacturer for proper work lead size.
Operation
General
The AC slave motor in the feeder runs at a fast, constant speed, but has very
low torque. It is always trying to feed more wire than the gun motor wants,
and when the gun motor gets all the wire it wants, the slave motor automati-
cally slows, preventing a bird’s nest. Because of the low torque produced
by the slave motor, a combination drag and electric brake system is used to
prevent wire overrun rather than relying on spindle tension alone. The spool
drag tension is produced by the patented Wire Retainer Bar mechanism to
keep the wire slightly taut. The 24 VDC gun “pull” motor is controlled by a
solid state speed control in the cabinet and through a potentiometer located
in the gun.
The normal operating sequence of the wire feeder can be viewed on the
board itself via sequence LED’s. When the system is triggered, the green
Trigger LED (L3) and the yellow Gas Solenoid LED (L1) illuminate simultane-
ously. The red Contactor/Wire Feed LED (L2) illuminates after the prepurge
time. The blue Arc On LED (LED) illuminates as the arc is established. When
the trigger is released the normal LED operating sequence is blue, green and
red (L4, L3, & L2) turn off simultaneously followed by the yellow (L1) after the
postpurge time has elasped (Figure 4).
Green LED
when triggered.
L3
Yellow LED
when gas
solenoid opens.
L1
Red LED when
wire feeds/
contactor closes.
L2
Blue LED
when arc established
L4
Figure 4 - L1, L2, L3 & L4
For reference, see Main PC Board Connections picture in Section F
Recommended Processes and Equipment
The Cobramatic ® Pro Series feeder is recommended for use with GMAW and
FCAW welding applications. It is recommended for use with constant voltage
power sources but will also work with CC machines. The Cobramatic
®
Pro
Series feeder is capable of feeding wires (diameter capacity) ranging from
.030” through .045” solid/cored and .030” through 1/16” aluminum.
Controls and Settings
On/Off Switch
Placing the switch in the “ON” position energizes the feeder circuitry and the
power indicator light.