Nelson ALPHA 850 - Page 55

9 Repairs Page 50
Stud welding unit operating manual Date: July 2021
ALPHA 850 07.2021 / EN Rev.: A
Fault: Overload/phase error
Features:
• ALPHA 850 is switched on
• “System voltage" LED lights up
• Gun doesn’t work when start triggered
• no weld
No.
Possible
cause
What is to be
tested or how?
Test
result
Test result achieved?
yes no
1
Device overloaded or
phase error
“Fault” LED lights green
or red?
Green LED No. 2
Red LED
No. 3
2
Phase error L1/L2/L3
Check power supply *)
(fuse, plug, cable)
Check the power cable
connection at the power
plug *)
Check the transformer
connection at the power
switch *)
Set the connection
voltage *)
White LED ready No. 7
3
Device overloaded,
inadequate cooling
Check fan *)
Fan runs No. 5 No. 4
4
Phase error L1
Fuse F4
1)
defective
Blower connection
fan
Check power supply *)
(fuse, plug, cable)
Check the fuse
(315 mA) *)
Check fan connection *)
Check fan *)
Features
removed
ready No. 7
5
Welding sequence
too high
Let the welding device
cool
Reduce the welding
sequence
White LED ready No. 6
6
Fan disabled or dirty
Improve air circulation *)
Check the ventilation
slots
Clean inside of device *)
White LED ready No. 7
7
PCB defective
Replace the PCB *)
Features
removed
ready No. 8
8
Transformer error
Shut down ALPHA 850
Notify Tucker service!
Tasks indicated with *) must be done only by electro-technical personnel!
1)
The arrangement of the F4 equipment fuse can be found in Chapter 6 “Equipment fuses”.