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If you want to just modify and add new thresholds reach read the first section "Using the NMIS GUI to Configure Thresholds", the second section "About Threshold Controls" goes into more details about thresholds.
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Access the NMIS Models GUI
Access the GUI by clicking on the menu "System -> System Configuration -> NMIS Models", the "NMIS Models" widget will be displayed as shown below. Now this is a BIG form, so clicking on the POP OUT button will place it in its own browser TAB/Window. This is application applicable in NMIS 8.4.8G and onwards.
NMIS 8.4 Example
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