Lincoln Na5 Service Manual

							NA-5F-38
TROUBLESHOOTING & REPAIRF-38
TEST DESCRIPTION
This will help determine if the power and logic boards are supplying the\
 correct DC voltages
to the NA-5 circuitry.
MATERIALS NEEDED
5/16 Nutdriver
Volt/Ohmmeter (Multimeter)
Wiring diagram
DC POWER SUPPLY TEST 
Service and repair should be performed only by Lincoln Electric factory trained per-
sonnel. Unauthorized repairs performed on this equipment could result in danger to
the technician or the machine operator and will invalidate your factory warranty. For
your safety and to avoid electrical shock, please observe all safety notes and precau-
tions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to perform
the tests/repairs safely, contact the Lincoln Electric service department for technical
troubleshooting assistance before you proceed.
Call (216) 383-2531 or (800) 833-9353 (WELD).
_____________________________________________________________
WARNING
This procedure takes approximately 16 minutes to perform.
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							F-39TROUBLESHOOTING & REPAIRF-39
TEST PROCEDURE
1.  Remove input power to the NA-5.
2.  Using the 5/16 nutdriver open thecontrol box PC board access door.
3.  Locate the power, logic, voltage, control and procedure boards.  See
Figure F.1
4.  Apply 115VAC to the NA-5  wire feeder at the correct pins.  See
wiring diagram. 5.  Perform the power supply checks as
described in Table F.1  If any of the
readings are incorrect (out of range)
or missing the power or logic board
may be faulty.  See wiring diagram.
Note: Do not unplug the molex con-
nectors.
Also check associated leads and
plugs for loose or faulty connec-
tions.
DC POWER SUPPLY TEST  (continued)
NA-5
FIGURE F.1 P.C. BOARD LOCATIONS
PROCEDURE
BOARD POWER
BOARD
LOGIC 
BOARD
CONTROL
BOARD VOLTAGE

BOARD
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							F-40TROUBLESHOOTING & REPAIRF-40
CHECK POINT TEST CONNECTOR LEAD NO. NORMAL
LOCATION DESCRIPTION PLUG PIN NO. ACCEPTABLE  VOLTAGE READING
CONTROL PC  CHECK +15VDC PIN 10 +525 + 14.0 - 16.0 VDC
BOARD  SUPPLY FROM PIN 9 -510 -
CONNECTOR POWER BOARD
PLUG TO
CONTROL BOARD
VOLTAGE PC  CHECK +15VDC PIN 3 +525 + 14.0 - 16.0 VDC
BOARD 12 PIN  SUPPLY FROM  PIN 7 -510 -
CONNECTOR POWER BOARD
PLUG TO
VOLTAGE BOARD
VOLTAGE PC  CHECK -10VDC PIN 6 -500 - 9.0 - 11.0 VDC
BOARD 12 PIN  SUPPLY FROM PIN 7+510 +
CONNECTOR POWER BOARD
PLUG TO
VOLTAGE BOARD
CONTROL PC  CHECK -10VDC PIN 14 -500 - 9.0 - 11.0 VDC
BOARD  SUPPLY FROM PIN 9 +510 +
CONNECTOR POWER BOARD
PLUG TO CONTROL BOARD
LOGIC PC  CHECK +110VDC PLUG J1 PIN 1+ 610 + 90 - 135 VDC
BOARD J1  SUPPLY FROM PLUG J1 PIN 2 - 500 -
CONNECTOR POWER BOARD
PLUG TO
LOGIC BOARD
DC POWER SUPPLY TEST  (continued)
NA-5
TABLE F.1  DC POWER SUPPLY CHECKS
525 +
510 -
525 +
510 -
500 -
510 +
500 - 510 +
500 -610 +
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							F-41TROUBLESHOOTING & REPAIRF-41
DC POWER SUPPLY TEST (continued)
NA-5
CHECK POINT  TEST  CONNECTOR LEAD NO. NORMAL
LOCATION DESCRIPTION PLUG PIN NO. ACCEPTABLE 
VOLTAGE READING
PROCEDURE  CHECK +15VDC PLUG J19 515 +
PC BOARD  SUPPLY FROM PIN 5 +
J19 CONNECTOR  LOGIC BOARD 14.0 - 16.0 VDC
PLUG  TOPLUG J19 500 -
PROCEDURE BOARD  PIN 15 - 
VOLTMETER   CHECK +5VDC TEST POINT
1.TP5 +
BOARD SUPPLY TP5 + PRODUCED 4.75 - 5.25 VDCON THE 
VOLTMETER TEST POINT
1.LEAD 510P -
BOARD 510P  -
SPEEDMETER  CHECK +5VDC TEST POINT
1.TP5 +
BOARD SUPPLY TP5 + 4.75 - 5.25 VDC PRODUCED 
ON THE  TEST POINT
1.LEAD 510P -
SPEEDMETER 510P  -
BOARD
TABLE F.1  DC POWER SUPPLY CHECKS (continued)
500 -
515 +
1.Scrape encapsulation from test points.
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							F-42TROUBLESHOOTING & REPAIRF-42
NA-5
TEST DESCRIPTION
This test will help the technician to determine if the T1 and/or T2 tran\
sformers are functioning
properly.
MATERIALS NEEDED
115VAC power supply
Volt-Ohmmeter (Multimeter)
5/16 Nutdriver
Slot head screwdriver
T1  and T2 TRANSFORMER TEST
Service and repair should be performed only by Lincoln Electric factory trained per-
sonnel. Unauthorized repairs performed on this equipment could result in danger to
the technician or the machine operator and will invalidate your factory warranty. For
your safety and to avoid electrical shock, please observe all safety notes and precau-
tions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to perform
the tests/repairs safely, contact the Lincoln Electric service department for technical
troubleshooting assistance before you proceed.
Call (216) 383-2531 or (800) 833-9353 (WELD).
_____________________________________________________________
WARNING
This procedure takes approximately 15 minutes to perform.
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							F-43TROUBLESHOOTING & REPAIRF-43
PROCEDURE
1.  Remove all input power to the NA-5.
2.  Using 5/16 nutdriver open the con-trol box PC board access door.
3.  Locate the T1 and T2 transformers. See Figure F.2
4.  Locate and remove the two sets of primary leads (#531B and #532)
from the upper terminal strip TS2.
Label leads for reassembly.  See
wiring diagram and Figure F.2 5.  Using the 115VAC supply carefully
apply 115VAC to the T1 primary
leads #531B and #532.
6.  Check for approximately 10VAC at the yellow secondary leads (#601
and #602).  See wiring diagram.
T1 and T2 TRANSFORMER TEST (Continued)
NA-5
FIGURE F.2  T1 AND T2 TRANSFORMERS
POWER
BOARD
LOGIC 
BOARD
UPPER
TERMINAL
STRIP
T1 TRANSFORMER
T2 TRANSFORMER
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							F-44TROUBLESHOOTING & REPAIRF-44
7.  Check for approximately 22VAC atthe blue secondary leads.  The blue
secondary leads are connected to
the logic board.  See wiring diagram.
8.  Check for approximately 18VAC at the white to red leads.  The white
and red leads are connected to the
power board.  See wiring diagram.
9.  Check for approximately 36VAC at the red to red leads.  Both red leads
are also connected to the power
board.  See wiring diagram.
10.  If  all the secondary voltages are
correct the T1 transformer is func-
tioning properly.
11.  If any or all of the secondary volt- ages are low or not present the T1
transformer may be faulty.
12.  Using the 115VAC supply carefully apply 115VAC to the T2 primary
leads #531B and #532. 13.  
Check for approximately 115VAC
at the orange secondary leads.
The orange leads are connected  to
the power board.  See wiring dia-
gram.
14.  Check for approximately 24VAC at the brown secondary leads.  See
wiring diagram.
15.  If  all the secondary voltages are
correct the T2 transformer is func-
tioning properly.
16.  If any or all of the secondary volt- ages are low or not present the T2
transformer may be faulty.
17.   Reconnect the primary leads
(#531B and #532) to the TS2 termi-
nal strip.
18.  Close and secure the access door.
T1 and T2 TRANSFORMER TEST (Continued)
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							F-45TROUBLESHOOTING & REPAIRF-45
NA-5
TEST DESCRIPTION
This test will aid the technician in determining if the transformer on t\
he voltage board is func-
tioning properly.
MATERIALS NEEDED
5/16 Nutdriver
Phillips head screwdriver
115VAC power supply
Volt/Ohmmeter
VOLTAGE BOARD TRANSFORMER TEST
Service and repair should be performed only by Lincoln Electric factory trained per-
sonnel. Unauthorized repairs performed on this equipment could result in danger to
the technician or the machine operator and will invalidate your factory warranty. For
your safety and to avoid electrical shock, please observe all safety notes and precau-
tions detailed throughout this manual.
If for any reason you do not understand the test procedures or are unable to perform
the tests/repairs safely, contact the Lincoln Electric service department for technical
troubleshooting assistance before you proceed.
Call (216) 383-2531 or (800) 833-9353 (WELD).
_____________________________________________________________
WARNING
This procedure takes approximately 15 minutes to perform.
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							F-46TROUBLESHOOTING & REPAIRF-46
TEST PROCEDURE
1.  Remove all input power to the NA-5.
2.  Using the 5/16 nutdriver open thecontrol box PC board access door.
3.  Locate the voltage board.  See Figure F.3 4.  Remove the molex type plugs from
the voltage board.
5.  Using the phillips head screwdriver remove the voltage board from the
control box.
6.  Locate the transformer and test points on the voltage board.  See
Figure F.4
VOLTAGE BOARD TRANSFORMER TEST(Continued)
NA-5
FIGURE F.3  VOLTAGE BOARD LOCATION
VOLTAGE
BOARD
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							F-47TROUBLESHOOTING & REPAIRF-47
7.  Using the 115VAC supply carefullyapply 115VAC to pins #8 and #9 in
the nine pin molex plug cavity on the
voltage board.  See Figure F.4
Make sure the board and leads are
insulated from each other and any
metal conductors.
8.  Using the voltmeter check for approximately 24VAC at the sec-
ondary test points.  See Figure F.4 
Note: The secondary voltage will vary
with the input primary voltage. The
insulating material will have to be
removed from the secondary test
points to insure that the meter probes
make good electrical contact.
9.  If the secondary voltage is correct the transformer is functioning proper-
ly. 10.  If 
the secondary voltage is low or
not present the transformer may be
faulty.
11.  Carefully remove the 115VAC sup- ply from the voltage board.
12.   Install the voltage board and con-
nect the molex plugs.
13.  Close and secure the access door.
VOLTAGE BOARD TRANSFORMER TEST(Continued)
NA-5
FIGURE F.4  TRANSFORMER TEST POINTS
NA-5
VOLTAGE
G1556-[ ]
VOLTAGE BOARD
TRANSFORMER
PIN #8
PIN #9 24VAC
SECONDARY
TEST POINTS
{
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