A-4
INSTALLATION
DC-400
A-4HI-FREQUENCY KIT (K799 CODES 8634AND ABOVE ONLY)
Kit supplies the high frequency plus gas valve for DC
TIG welding. The DC-400 is shipped with proper R.F.
bypass circuitry installed to protect the control circuit
when welding with a HI-FREQ unit. K844 Water
Valve Option Kit can be used with K799 when TIG
welding with water cooled torches. See Hi-Frequency
Kit Instruction Manual for installation information.
AMPTROL ADAPTER FOR K799 HI-FRE-QUENCY KIT (K915-1, REQUIRES K864ADAPTER)
A“V” cable to connect a K799 Hi-Freq Kit (5-pin con-
nector) with either a K963 Hand Amptrol or a K870
Foot Amptrol (6-pin connector) and the machine. The
cable going to the machine has a 6-pin connector
which requires a K864 adapter to connect with the 14-
pin connector on the DC-400. Refer to S20909
instructions for connection information.
MULTIPROCESS SWITCH (K804-1)
Kit that mounts on the front of the DC-400, and
includes hinged covers over its output studs. The
switch has three positions: Positive
semiautomatic/automatic, negative semiautomatic
/automatic, and stick/air carbon arc. Required when
using the DC-400 for both semiautomatic/automatic
and stick/air carbon arc.
Install per M17137 instructions included with the field
installed kit.
CAPACITOR DISCHARGE CIRCUIT (K828-1)
Circuit that mounts inside the DC-400.
Recommended when:
1) DC-400 is used in conjunction with any LN-23P or
older LN-8 or LN-9 semiautomatic wire-feeder.
Eliminates possible arc flash re-start of weld when
trigger interlock is used. Not required with current
LN-8 (above Code 8700), or LN-9’s with serial
numbers above 115187 (manufactured after
12/83), or any LN-9 having an L6043-1 Power PC
Board.
2) DC-400 is used with an LN-22 equipped with an
older K279 Contactor-Voltage Control Option.
Eliminates electrode overrun when gun trigger is
released. Not required when later K279 (above
Code 8800) is used.
3) DC-400 is used with any semiautomatic wire-feed-
er and possible small spark, if electrode touches
work just after gun trigger is released, is objection-
able.
Install per M17060 instructions included with the
Kit.
UNDERCARRIAGES (K817, K817R, K841)
For easy moving of the machine, optional undercar-
riages are available with either steel (K817) or rubber
tired (K817R) wheels or a platform undercarriage
(K841) with mountings for two gas cylinder at rear of
welder.
Install per instructions provided with undercarriage.
INSTALLATION OF EQUIPMENTREQUIRED FOR RECOMMENDEDPROCESSESWIRE FEEDER CONTROL CABLE CONNEC-TIONS
For control cable with 14-pin connector:
Connect control cable to 14-pin connector on the front
panel of the machine. See the appropriate connection
diagram for the exact instructions for the wire feeder
being used. Refer to Section 2.4.1 for connector pin
functions.
For control cable with terminal strip connectors:
The control cable from the wire feeding equipment is
connected to the terminal strips behind the control
panel*. A strain relief box connector is provided for
access into the terminal strip section. A chassis
ground screw is also provided below the terminal strip
marked with the symbol for connecting the auto-
matic equipment grounding wire. See the appropriate
connection diagram for the exact instructions for the
wire feeder being used.
A cover (Lincoln Electric Part Number S17062-3) is
available for the unused 14-pin connector to protect it
against dirt and moisture.
* See Terminal Strip Connections section for access
to the terminal strips.