Troubleshooting - MAC TOOLS MW250 Owner's Manual

5-5.
Troubleshooting
READ SAFETY BLOCKS
at start
of
Section 5 before
proceeding.
SECTION 6- ELECTRICAL DIAGRAM
SB-174
099-A
Welding Trouble
I
No weld
output;
wire does
not
feed.
I--.
Remedy
Secure power cord
plug in receptacle.
No weld
output;
wire does not feed;
fan I.
-.
motor continues to
run
and pilot light is
oft.
Reset circuit breaker CB1
-
Replace fuse Fl and/or F2.
Replace building line fuse
or
reset
circuit breaker if open
Secure gun trigger plug in receptacle
or
repair leads,
or
replace
trigger
switch.
I
No weld
output;
wire feeds.
Section
-~
3-6
-~
5-2
-~
3-6
-~
3-5
Thermostat open (overheating). Allow fan to
run;
the thermostat
will close when the unit has cooled.
Low weld
output.
I -ui
Connect work
clamp to
get
good
metal
to metal contact.
Replace
contact tip.
Wire Drive/Gun Troube
-~__5-2
Electrode wire feeding
stops during
I-.
welding. I
-
Connect unit
to
proper
input voltage
or
check for low line voltage.
~ --~
3-6
:I___u~
Figure 4-3
J-I.
5-4
--~
5-4 Straighten gun cable and/or replace damaged
parts.
Adjust
hub tension.
Adjust
drive roll pressure.
Replace contact tip it blocked.
Clean
or
replace
wire inlet
guide
or
liner if
dirty
or
plugged.
Replace drive roll
or
pressure
bearing if
worn or
slipping
Secure gun trigger plug in receptacle
or
repair leads,
or
replace
trigger switch.
Check and replace Fl and/or F2.
Check and clear any restrictions
at drive assembly and liner
Have nearest
Factory
Authorized Service Station check drive
motor.
--a
--a
--a
--a
-a
-a
3-7
3-8
5-4
5-3, 5-4
5-3
3-5
-a
-a
-a
5-2
5-3,
5-4
5
pr ~ ~
~
>>~<
~
I
~3-l)>----~<4 ~J
~3-3
>>____~z<
~3-2
>>~(
~
~3-~
~3-t
>>~<
2
QJ~p
Figure 6-1. Circuit
Diagram For Welding
Power Source
OM-154 501
Page
17