Operation – Lincoln Electric LN-9 SVM127-A User Manual
Page 39
ADJUST THE LN-9 CONTROLS
1.
Set the "Electrode Polarity" switch to same polarity
as the electrode lead.
2.
Connect the "Direct Work Lead" if it is going to be
used.
3.
Check that "Feed Direction" is set to forward.
4.
Set the "Trigger Interlock" switch as desired.
5.
Set the "Meter Reading" switch to "Wire Speed"
and adjust the "Wire Speed" rheostat so the meter
reads the desired wire feed speed.
6.
Set the "Meter Reading" switch to "Volts" and
adjust the "Volts" rheostat so the meter reads the
desired arc voltage. IMPORTANT: Make certain
this setting is within the voltage output range of the
power source setting.
7.
Load the LN-9 with electrode.
VOLTAGE CONTROL RESPONSE
The LN-9 is provided with selectable voltage control
response. Proper setting depends on the power
source and process being used. Refer to the appropri-
ate power source connection diagram for the proper
connection of the jumpers located on the LN-9 Voltage
PC Board and Start PC Board (only in models using L-
6084 Voltage PC Board).
To change the voltage control response:
1.
Turn OFF the control power to the LN-9 at the
power source.
2.
Remove the screws holding the control section
cover in place and swing open.
3.
Position the jumper plugs on the Voltage Board
and Start Board (where used) according to the
appropriate power source connection diagram.
4. Reassemble.
STARTING CHARACTERISTICS
SELECT ACCELERATION
The LN-9 models can provide optimum starting for dif-
ferent processes. The wire feeder is designed to start
with two different speeds of controlled acceleration. As
shipped, it is connected for fast acceleration, which is
the best for most open arc procedures. However, the
slower acceleration may be more desirable for Linc-Fill
long stickout applications and most submerged arc
procedures. If the electrode being used does not give
satisfactory starting because of "stubbing" or "blasting
off," slower acceleration can be obtained by modifying
the LN-9 models as follows:
1.
Turn OFF the control power to the LN-9 at the
power source.
2.
Remove the screws holding the control section
cover in place and swing it open.
3.
Move the jumper plug on the Control PC board
from pin "F" to pin "S."
4.
Reassemble.
START VOLTAGE TRIM
The start voltage is the voltage provided by the welding
power source before establishing the welding arc. This
start voltage setting is a function of the open circuit
voltage characteristic of the power source, the SET
value of the weld voltage, and the start voltage trimmer
(R41) setting on the LN-9 Voltage PC Board. As set at
the factory, the start voltage trim level is typically about
20% higher than the LN-9 SET level. This generally
gives good starting for steel cored and MIG processes
using CO
2
or Argon/CO
2
blended shielding gas. If you
are using "hotter" gases (such as Argon/Oxygen
blends) and other processes (such as stainless steel
MIG), arc flaring may occur at start, which requires low-
ering the start voltage trim as follows:
1.
Turn off the control power to the LN-9 at the power
source.
2.
Remove the screws holding the control section
cover in place and swing it open.
3.
On the voltage board, locate trimmer R41 (below
R40 next to the 1/8 amp fuse) and labeled START.
4.
The slot on the START trimmer is marked with a
red seal for factory setting. To decrease the facto-
ry setting, turn the slot CCW (opposite to the
labeled arrow direction).
NOTE: If the start trim is set too low, stubbing may
occur at start, requiring increasing the START trimmer
by turning the slot CW (in the direction of the labeled
arrow).
5. Reassemble.
OPERATION
B-19
B-19
LN-9 Wire Feeder