Lincoln Electric 50448 Service Manual page 55

FEEDER CONTROL BOARD TEST (continued)
TEST PROCEDURE
Use always electrically insulate gloves during this test procedure
1. Remove input power from the wire feed unit.
2. Perform the wire feeder case removal procedure.
3. Located the Feeder Control Board. See Figure 1. Do not remove the plugs from the Motor Control Board.
4. Visually check for burned or damaged components. If any components are physically damaged the motor control
board has to be replaced.
5. Apply the correct input power to the wire feeder connecting it through control cable to the power source.
6. Using the multimeter perform the tests as indicated in Test Table 1. See Figure 1a for correct test points location.
LEDs Table
LED Description
V301
+24 Vdc
V320
3,3V dc
V112
Status LED green
+5Vdc Remote supply
V519
voltage
X11: Voltage Supply to User Interface
Pin # Description
3 Power supply
to UI board
4
X7: Feeder Board to Gas Purge/Cold inch Switch
Pin # Description
8
Cold inch
5
8
Gas purge
3
X12: Feeder power supply
Pin # Description
Feeder
3
Power supply
from power
4
source
X1: Voltage Supply to Gas solenoid
Pin # Description
1
Gas solenoid
power supply
2
X9: Tachimeter and drive motor supply
Pin # Description
1
Drive motor
power supply
3
4
Tachimeter
supply
5
4
Tachimeter
feedback
6
X16: Illumination Power Supply
Pin # Description
1
Internal light
power supply
4
Status
Always ON GREEN
Always ON (GREEN)
Always ON after about 10 seconds from
Power ON
Always ON (GREEN)
Value
+40Vdc +/- 0,1V
Value
+15 Vdc +/-10%
+15 Vdc +/-10%
Value
+40Vdc +/- 0,1V
Value
+22,5 Vdc +/- 10%
Value
From 2VDC to 21,5VDC
+5VDC
Approx. 2,5VDC
when motor is running
Value
24VDC
For LF56D
It indicates that the 24Vdc is present
It indicates that the 3,3 V dc is present
Indicated correct machine status
It indicates that the remote voltage supply is
Notes
Power supply for the User Interface Board
Notes
When Gas purge switch is pressed the voltage drops to 0
(zero)
When cold inch switch is pressed the voltage drops to 0
(zero)
Notes
Power supply coming from the power source
Notes
This is a PWM signal and the reading can be different from
multimeter to multimeter, it is recommended to use the
oscilloscope to perform this test -> see picture below
Notes
Press the gun trigger for this test. Expected reading
dependent upon WFS setting
Tachimeter voltage supply
When motor is not running 0VDC or 5VDC
Depend upon where the motor is stopped
Notes
Wire drive lamps power supply
Notes
present