Operator`s manual

Advanced Haas Mill Programming Techniques Training Manual Page 11
Haas Fixture Clamp Input (Mill Parameter 738)
In high production environments it is easy for the machine operator to forget to clamp a fixture or vise
before the cycle start button is depressed. During the normal work routine the operator may be
interrupted or distracted and fails to clamp the vise or collet. When this happens the tool is usually
destroyed and the vise jaws or fixture become damaged and need replacement. To prevent this from
happening Haas provides a Fixture Clamp Input. It is available on mills with software version of 15.05A or
higher.
Open and close clamp switches are required. If a hydraulic vise is used a pressure switch may put on the
hose going to the vise. A similar arrangement may be used If a pneumatic clamping device is used. Limit or
proximity switches may also be used in fixture clamping.
The clamp switch is connected with a cable to a discreet input connector on the I/O Board. The machine
interprets an open switch as a fault indicating the fixture is in the unclamped position during the machine
cycle. Parameter 738 indicates the input number on the I/O Board.
If the spindle is on and the Haas mill controls sees that the part is unclamped (open circuit on the I/O
Board) Alarm 793 Fixture Clamp Failure is generated which stops the spindle and program. This not only
works at the beginning of the program but also if the part becomes unclamped in the middle of the cycle
for some reason. The alarm comes on only when the spindle is commanded on. This means that a part
may be unclamped in the middle of the cycle as long as the spindle is not commanded on without
generating an alarm.
See Haas ES0670 rev A 10/08 titled Fixture Clamp Input which is included on the next page for details on
installation.