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NS20A & NS20N Heavy Duty Gun
Page 10
Revision 1.20 2/19/08
MAINTENANCE INSTRUCTIONS
Part Number Designation
The Nelson Heavy Duty handgun has been designed for use with various Nelson Stud Welding Systems. The
basic construction of the gun remains the same - only the control cable and trigger switch assembly change for
proper interconnection with the control unit. The correct gun number may be determined per the following
table:
Heavy Duty
Gun Part
Number
751-535-000
751-535-100
751-535-500
751-693-000
For Use With
Series 6000 (TR-2400)
Series 5000 (TR-1600)
with 4 wire control
Series 3000 (NS-20AHD)
with 3 wire control
Series 6000 (TR-2400)
Series 5000 (TR-1600)
with 2 wire control
Nelweld Power
Sources
with 2 wire Control
Control Cable
Description
6 pin – 4 wire
4 pin – 3 wire
3 Pin 2-Wire
3 Pin 2-Wire
Control Cable
Part Number
721-194-000
721-194-001
721-215-000
721-215-000
Control
Connector
Type
Cannon
R & S
Hubbell
Hubbell
Control
Connector
Part Number
714-083-002
714-061-000
714-174-000
714-174-000
Control
Connector
Boot
N/A
N/A
714-174-002
714-174-002
Trigger
Switch
Assembly
709-028-100
709-028-100
709-028-200
709-028-200
Connector
Pin-out
Pin
Description
1
No Connection
2
Red (To Red Coil Lead)
3
White (To Trigger)
4
Black (To Trigger)
5 Green (To Green Coil Lead)
6
No Connection
Pin
Description
X
No Connection
Y
Green (To Green Coil Lead)
Z
Black (To Trigger)
Small
Pin
White (To Trigger)
Pin
Description
Silver
White
Brass
Black
Center No Connection
Pin
Description
Silver
White
Brass
Black
Center No Connection