DISA Loadable Function Block Installation and User Guide

The Disabled Discrete Monitor (DISA) is a loadable function, an instruction that monitors disabled coils and inputs. DISA monitors the disabled states of all 0xxxx and 1xxxx addresses. A DISA Loadable function block instruction allows the ladder diagram of a Quantum or Compact PLC to find and annunciate disable states as they occur. The instruction logs the quantity and reference number of the disabled coils and inputs into simple data tables enabling the controller to annunciate this information locally. HMI systems and other host devices can perform the same service at remote locations. A common problem with disabling inputs & coils is ensuring removal and restoration to the normal operating mode of the control system. Failure to document the user-initiated override for correction can result in additional problems. The DISA instruction fixes this problem by alerting programmers and maintenance personnel to the presence of inputs and coils disabled in logic.NOTE: This re-posting reflects the following changes to the PDF:Changes for Page 3 -- "Detailed Description" edited, "Installation" edited regarding the "Note."Changes for Page 4 -- "Note" edited just above the "Description Table," new blocks "Baseline Information" and "Compatibility Information" added.