LINK Systems OmniLink II Press Automation Control - Manual (Page 82)

August 30, 2002 Manual Version 1.0 4.33
Section 4.2.4.4 Auxiliary Communications Setup
The AUXILIARY COMM. SETUP softkey provides access to the configuration screens for the
communication options. These options include serial communication ports for interfacing to electronic
servo feeds, auxiliary equipment (such as PLCs), a laptop interface for downloading messages, and a
network interface. See the manual pertaining to the particular device that is connected for
communication for auxiliary communications setup for that device.
Section 4.2.5 Auxiliary Equipment Messages
The OmniLink II Press Automation Control makes provision to wire inputs to its parallel port on the
back of the operator terminal from the intelligent controller (such as a PLC) of auxiliary equipment so
that diagnostic messages from auxiliary equipment can be displayed on the brake monitor screen of the
operator terminal. Wiring is shown in Figures 2.20 in Section 2.6 of this manual. The OmniLink II
operator terminal interprets inputs 2 – 8 on the parallel input port as binary number bits with input 2
representing 2
0 (the least significant binary bit) and input 8 as 2 6 . Input 1 on the parallel port must be
connected to the ground of the controller sending the signals to inputs 2-8. The 128 binary numbers
available for message codes and their decimal equivalents are:
Binary Decimal
0000000 0
0000001 1
0000010 2
0000011 3
0000100 4
0000101 5
0000110 6
0000111 7
etc. etc.
The message codes sent to the parallel port from auxiliary equipment may indicate conditions that
prevent stroking the press, such as “Feed Fault”, or may simply give information about the status of
auxiliary equipment, such as “Feed Automatic Mode” or “Feed Manual Mode”. In either case, the
person that programs the PLC to send the desired message codes needs to prioritize the messages sent to
the parallel port in case several conditions that are assigned a message code are present at the same time.
Generally, all message codes from auxiliary equipment that are associated with the assertion of a stop
signal from auxiliary equipment to the press clutch/brake control should take priority over messages that
provide status information. A simple way to prioritize is to always have the PLC assert the lowest
binary number message code when more than one condition exists. Assign all message codes associated
with the assertion of a stop signal from auxiliary equipment to the press clutch/brake control to a lower
group of binary numbers. Also, within this group, the lower the binary number the higher the priority in
the order that you want the message displayed. Assign all messages associated with status information
(and no associated stop signal) to a higher group of numbers than those message codes associated with
stop signals from auxiliary equipment to clutch/brake control. Again, within this group, the lower the
binary number assigned, the higher the priority in the order that you want the message displayed.