Theory Of Operation - YASKAWA MOTOMAN DX100 Instruction Manual

Auto-Axcess DI/E Digital
4

Theory of Operation

4 Theory of Operation
The Auto-Axcess is a Gas Metal Arc Welding (GMAW) power
supply capable of non-pulsed, or MIG, and pulsed
(GMAW-P) modes of operation.
The DX100 utilizes a DeviceNet interface to the Auto-Axcess. This
interface provides two basic levels of controls:
• Real time display of weld data.
• Programming of welder set-up data from the teach pendant.
Operators will not be aware of any programming difference between
Digital or Analog interfaces with the
function with the INFORM weld instructions utilized on the DX100
controller. The digital interface uses an application created by Motoman
called the Miller HMI. This provides pendant screens with dialog boxes to
allow Managers or Operators (if allowed by Managers) to make changes
to programs in the welder.
The weld settings and sequence of operation are controlled by the robot.
Traditionally, the current and voltage settings were communicated to the
welder as a proportion of a 0-14 volt analog signal. The weld contactor,
arc establish input, and error signals were discrete inputs and outputs.
These basic signals were interfaced between the XEW01 board in the
controller to the Auto-Axcess with a cable that had about a dozen wires.
These commands and signals are set and sequenced through the
controller's concurrent I/O (CIO) program. This program has a system
section which can not be edited by Users because of Safety functionality.
The User section is provided for users to add fixture and cell control logic.
INFORM functions such as RETRY and ANTI-STICK use signals in the
ladder to operate. Motoman developed the HyperStart function to allow
users to set values used in the system section to optimize cycle time and
arc alarm conditions to suit the application.
The standard Auto-Axcess interface addresses the welding input and
output signals to the physical I/O points on the XEW01 board. Weld
settings, current and voltage, are entered in the robot program as an
INFORM command or Arc Start File. These settings (i.e. 200 amps, 18.0
volts) are converted to a proportional analog value by referencing the
Welder Condition File. The Welder Condition File is a table of 8 settings
that allows the robot to be scaled to different wire types and power
supplies. In the case of the Auto-Axcess, the Welder Condition File is
scaled to be 0-999 ipm wire feed speed (instead of amperage) and 0-50.0
volts.
Auto-Axcess
When the is in a pulse mode, then the voltage value is 3/4
of the arc adjust setting (i.e. arc voltage setting of 22.5 provides an arc
adjust setting of 45 on the welder). The arc adjust setting on the
Axcess
has a setting of 0-100 with a nominal setting of 50. The welder is
synergic which means an arc adjust value of 50 will provide good welding
conditions through the whole range of wire feed settings. Users may want
to reduce the arc adjust setting to get a shorter arc length to suit a given
application.
4-1
Auto-Axcess
. Both interfaces
166465-1CD
166465-1CD
Auto-
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