Aerotech UNIDEX 600 Series, User Manual

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Getting Started U600 User’s Guide
2-12
Aerotech, Inc.
Version 1.4
2.6.1. FAULT
The FAULT axis parameter, when non-zero, indicates an axis fault condition. The value is
a bit mask, indicating one or more faults that occurred on that axis (see Table 2-5) These
conditions are all on a per axis basis, meaning they can occur independently for each axis.
Most fault conditions have threshold values that are set via other axis parameters, refer to
Table 2-5
The U600MMI will report an axis fault by blinking the appropriate message in the
position display. The user can also view the value of the FAULT parameter, along its bit
breakdown in AerStat (which bits indicate which faults). AerDebug also reports the fault
value with a “PARMGET A FAULT” command, but it will not provide a bit breakdown.
The value of the FAULT parameter remains set until the fault is acknowledged by the user
or the application program. Writing its bit value back to the axis fault parameter clears a
fault. For example, if the FAULT parameter indicated the CW, CCW and Position Error
Limit faults occurred, the FAULT parameter would indicate a value of 13. Setting the
FAULT axis parameter to 13 would clear all those faults. Setting it to 12 would clear the
CW and CCW faults, but not the position error limit fault. Alternately, all faults may be
simultaneously cleared by setting FAULT to a value of –1 (-1 = 0xffff). Pushing the Fault
Acknowledge button on the U600MMI is equivalent to setting the FAULT axis parameter
to –1. The user cannot acknowledge a fault with the AerStat utility.
2.6.1.1. Axis Faults and Programming
The Programming and Task axis faults listed in Table 2-5 (bits 8 and 16) exist to trap
faults generated by faulty programming from the two interfaces: library and CNC,
respectively. A programming Axis fault occurs when a faulty library call involving the
given axis executed. A Taskfault Axis fault occurs when a faulty CNC command executes
and the Taskfault bit is on in the FAULTMASK for that axis. Refer to Chapter 3:
Programming for more details.
Often these programming interfaces provide additional protection. For example, velocity
and velocity command faults are generated when exceeding the axis parameters
VELTRAP and VELCMDTRAP. However, when programming from the CNC interface,
additional protection is available in the RapidFeedRateIPM and RapidFeedRateRPM task
parameters. If these are violated, the system generates a Task fault (see section 2.7).
The C/C++ programmer also has the User Axis Fault available (see chart), where they can
force an axis fault.