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TB085 Rev1 Spindle Override Disabling
Overview
In software version 7 07 CPU7 PLC I/O assignments have been expanded to include a Spindle Knob
Enable/Disable bit that is mapped to OUT80 This document describes the behavior and implementation of the
spindle knob enable/disable function
Defined behavior
OUT80 in a PLC program has been defined as a Spindle Knob Enable/Disable bit A value of one will set the
spindle speed to 100% of the commanded value In Automatic spindle mode setting OUT80 = 1 will cause the
spindle speed to be that of the last S command in effect In manual spindle mode setting OUT80 = 1 will
cause the spindle speed to be changed to approximately 50% of the difference between maximum and
minimum spindle speeds When OUT80 = 0 the spindle speed may be overridden by adjusting the spindle
override knob
Typical Implementations
Typical implementations modify the PLC program to toggle OUT80 via an AUX key with a visual indication
being mapped to the AUX LED output All PLC programming required to implement the spindle override
function is demonstrated below Changes to the input output memory and program sections of the example
PLC program are using the AUX4 key as the toggle input Note that MEM31 may already be used in an
arbitrary PLC program and may require the use of a memory bit that has not been previously defined or used
in the program section
Changes in the input section of the PLC program
Aux_4_key IS INP52 ; 1 = pressed
Changes in the output section of the PLC program
Aux_4_LED IS OUT52 ; 1= on 0 = off
SpinOverride IS OUT80 ; 1 = Override Disabled 0 = Enabled
Changes in the memory section of the PLC program
Last_aux_4 IS MEM31 ;
Changes in the program section of the PLC program
Aux_4_LED = Aux_4_LED XOR Aux_4_key AND / Last_aux_4
SpinOverride = Aux_4_LED
Last_aux_4 = Aux_4_key
Document History
Rev1 Created on 2000 01 14