Cable Inductance And Its Effects On Welding; Remote Sense Lead Specifications - Lincoln Electric POWER WAVE S700 Operator's Manual

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CABLE INDUCTANCE AND ITS
EFFECTS ON WELDING
Excessive cable inductance will cause the welding
performance to degrade. There are several factors
that contribute to the overall inductance of the cabling
system including cable size, and loop area. The loop
area is defined by the separation distance between
the electrode and work cables, and the overall welding
loop length. The welding loop length is defined as the
total of length of the electrode cable (A) + work cable
(B) + work path (C) (See Figure A.10).
To minimize inductance always use the appropriate
size cables, and whenever possible, run the electrode
and work cables in close proximity to one another to
minimize the loop area. Since the most significant fac-
tor in cable inductance is the welding loop length,
avoid excessive lengths and do not coil excess cable.
For long work piece lengths, a sliding ground should
be considered to keep the total welding loop length as
short as possible.
REMOTE SENSE LEAD
SPECIFICATIONS
Voltage Sensing Overview
The best arc performance occurs when the Power
Wave ® S700 has accurate data about the arc condi-
tions.
Depending upon the process, inductance within the
electrode and work cables can influence the voltage
apparent at the studs of the welder and can have a
dramatic negative effect on welding performance. To
counteract this negative effect, remote voltage sense
leads are used to improve the accuracy of the arc volt-
age information supplied to the control pc board.
Sense lead kits (K1811-XX) are available for this pur-
pose.
INSTALLATION
FIGURE A.10
B
POWER WAVE
There are several different sense lead configurations
that can be used depending on the application. In
extremely sensitive applications it may be necessary
to route cables that contain the sense leads away
from the electrode and work welding cables.
CAUTION
If the auto sense lead feature is disabled and
remote voltage sensing is enabled but the sense
leads are missing or improperly connected
extremely high welding outputs may occur.
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Electrode Voltage Sensing
The remote ELECTRODE sense lead (67) is built into
the wire feeder control cable and accessible at the
wire drive. It should always be connected to the wire
drive feed plate when a wire feeder is present.
Enabling or disabling electrode voltage sensing is
application specific, and automatically configured
through software.
A
C
® S700
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WORK