Pm Trigger
A PM Trigger is a rule within a CMMS that automatically initiates a Preventive Maintenance work order at predetermined intervals or when a measured threshold is crossed. It distinguishes between time-based (calendar), usage-based (meter/cycles), and condition-based (sensor threshold) methods, ensuring tasks like lubrication or inspection occur without manual scheduling.
On the shop floor, PM Triggers generate work orders in a technician's queue when an asset hits '500 operating hours' or the date 'every Monday,' automating the maintenance lifecycle. ServiceGrid utilizes these triggers to convert asset usage data from process historians or calendar dates into actionable work orders. Time-based triggers create work orders on fixed schedules for assets with predictable wear or regulatory needs. Usage-based triggers monitor meters like runtime hours, considered the 'gold standard' for efficiency. Condition-based triggers use IoT sensors to create work orders only when readings exceed thresholds, preventing over-maintenance on healthy assets. Fixed triggers alert at rigid multiples, while floating triggers calculate from the last completion point, keeping assets closer to manufacturer-recommended cadences.
How does a PM Trigger differ from a PdM (Predictive Maintenance) trigger?
A PM Trigger initiates work based on elapsed time/usage or a static condition threshold (e.g., 'every 500 hours' or 'temp > 80°C') regardless of failure trend forecasting. A PdM Trigger uses analytics to forecast failure timing (e.g., 'failure likely in 14 days') and initiates work only when the forecasted window is imminent.
What is the impact of 'Floating' vs. 'Fixed' triggers on MTBF (Mean Time Between Failures)?
Floating triggers generally improve MTBF on critical assets by ensuring the maintenance interval remains consistent relative to the last completed task, preventing the 'drift' away from manufacturer specs that occurs with Fixed triggers when tasks are missed.
How are usage-based triggers integrated with process historians in ServiceGrid?
The CMMS subscribes to usage readings (e.g., kWh, cycles) from a process historian; when the reading passes a designated threshold (e.g., 5,000 cycles), the system automatically generates the work order without manual intervention.