Lincoln Electric PRO IM10031-A - Manual (Page 28)

b-10 OPERATION b-10
GAS PURGE PUSHbUTTON
The gas solenoid valve will energize but neither the
power source output nor the drive motor will be turned
on. The Gas Purge switch is useful for setting the
proper flow rate of shielding gas. Flow meters should
always be adjusted while the shielding gas is flowing.
FLOW METER
The flowmeter shows the flow rate of shielding gas
and has a valve to adjust the flow. The flow meter is
scaled for CO
2
, Ar, and Ar/CO
2
blends. The middle of
the ball indicates the flow rate of shielding gas.
Adjust the flow rate while depressing the GAS
PURGE switch by turning the valve at the bottom of
the meter. Most weld procedures require 25-40 scfh
(11.8 - 18.9 lpm) for sufficient shielding gas coverage.
Gun angle, nozzle diameter, joint configuration and
wind conditions may effect the amount of shielding
gas required.
When using a wire feeder with
a flow meter, adjust the regu-
lator at the shield gas bottle or
supply to a flow rate that is
higher than the flow rate indi-
cated on the feeder flow
meter. Note that most regula-
tors are calibrated based upon
having low restrictions on the
outlet. The valve on the feeder
flow meter creates a high
restriction and may cause
errors in the readings at the
supply regulator. Set the gas
flow rate using the feeder flow
meter reading and not the
supply regulator reading.
SCFH Liter/Min.
10 4.7
20 9.4
30 14.2
40 18.9
50 23.6
60 28.3
70 33.1
80 37.8
LN-25™ PRO
10 20 30 40 50 60 70 80 90 Va lv e B a ll
10
20
30
40
50
60
70
80
90
Valve
Ball
POWER-UP SEQUENCE
On feeders with analog voltmeters, the thermal LED
will briefly light during power-up.
If the gun trigger is activated during power up, the
feeder will not operate until the gun trigger is released.