Control board, Theory of operation, General description – Lincoln Electric LN-25 SVM179-B User Manual
Page 40
THEORY OF OPERATION
E-2
E-2
LN-25™ PRO
GENERAL DESCRIPTION
Several models of the LN-25™ PRO are offered to best
meet the individual welders needs. The Extra Torque
model features additional torque for reliable feeding of
large diameter FCAW wire. The standard and control
cable models feature wire drive gearing for optimal per-
formance with both FCAW and GMAW wires of com-
mon sizes. All the models include a gas solenoid and
flow meter for the flexibility to run most wire processes.
Control Cable models also includes digital meters and
remote voltage control.
The plastic case is molded from high impact, flame
retardant plastic for durability and low weight. The
patent pending design keeps the internal components
protected and dry.
FIGURE E.2 — GENERAL DESCRIPTION
The heart of the LN-25™ PRO is a 2 roll MAXTRAC
wire drive system. The patented features on the wire
drive offer tool-less changing of the drive rolls and wire
guides for quick changeovers. A tachometer controlled
motor powers the patent pending drive rolls for smooth,
steady feeding without slippage.
With only one p.c. board, the LN-25™ PRO is designed
to be simple, reliable and easy to service. The p.c.
board is manufactured with Lincoln’s industry leading
environmental design protection which involces mount-
ing the board in a plastic tray and potting it with epoxy.
With a 325 amp, 100% duty cycle rating, these feeders
are ready for heavy duty welding.
NOTE: Unshaded areas of Block Logic
Diagram are the subject of discussion
ELECTRODE
INPUT
CONTROL BOARD
FEEDPLATE
MOTOR
TACH
67
CONTACTOR CURRENT TRANSDUCER
INPUT
SOLENOID
V M
POLARITY
TIMER OPTION
MOTOR
OVERLOAD
21
21
ARMATURE
TACH FEEDBACK
GUN TRIGGER
GUN
RUN IN
DIGITAL
DISPLAY
BOARD
COLD
FEED
CC
CV
TRIGGER
INTERLOCK
GAS
PURGE
WIRE
SPEED
REMOTE
VOLTAGE
14 PIN AMPHENOL
1