24
A3 MIG Welder
© Kemppi Oy 2018
1826
OPERA
TING M
ANU
AL
On/Off control
The touch sensor device behaves as a software controllable power source. The
power source can be switched on and off from the robot controller by using the
digital robot interface.
The touch sensor cannot be used when the welding cycle is on.
Voltage source, levels and safety
The touch sensor provides four selectable DC voltage levels. The voltage level can
be configured by using the DIP switches 1 and 2 on the panel (2).
Panel (2) switches 1-2
Nominal
Minimum
Typical
Maximum
ON
1
2
3
4
5
6
7
8
50 V
(default)
47.5 V
54.0 V
58.0 V
ON
1
2
3
4
5
6
7
8
80 V
76.0 V
80.0 V
84.0 V
ON
1
2
3
4
5
6
7
8
110 V
104.0 V
108.0 V
113.0 V
ON
1
2
3
4
5
6
7
8
200 V
190.0 V
200.0 V
210.0 V
All levels have limited continuous power supply to ensure human safety. The
200 V supply drops down under the 113 V level when loaded by a 5.6 kΩ resistor
which is the nominal DC resistance of the human body. In some cases, voltage levels
above 113 V can still cause minor harm, such as pain, to a person.
The power source and the touch sensing circuitry are galvanically isolated from the
other systems in the welding power source.
Touch tool
Two alternative touch tools can be used for touch sensing (see
Figure 4.5, “Welding wire
used as touch tool”
and
Figure 4.6, “Gas nozzle used as touch tool”
). The regular tool is
the welding wire (welding plus). Sometimes the welding wire is not accurate enough.
The tip of the welding wire can bend resulting in incorrect position information. In that
case the gas nozzle can be used instead. Using the gas nozzle requires extra wiring from
wire feeder’s 7-pin peripheral connector (pin C) to the gas nozzle. The touch tool can be
managed by the robot controller by using the digital robot interface.
Figure 4.21 Welding wire used as touching
tool
Figure 4.22 Gas nozzle used as touching tool
