Welcome to the Corvus Online FAQ System.
Frequently Asked Question
Report: The default dates are set for “Monthshiftstart” and “todayshiftstart” however the default always appears as 6th,7th or 8th Jan 2018?
This issue is due to the settings of the Windows date and time format. The conflicts between Australia and US setting convert August (month) to 8th (day). To solve this, go to Windows Control Panel, choose Clock and Region:
The MTBF data for report 300 does not seem to add up? How is this calculated?
Mean Time Between Failure (MTBF) is a measure of equipment reliability expressed in hours. It is defined as the sum of operational periods divided by the number of observed failures. The operational periods are measured as available time.
Available Time (AT) = Non-Value Production Time (NVPT) + Production Time (PT) + Scheduled Process Downtime (SPD) + Unscheduled Process Downtime (UPD)
MTBF:
Mean Time Between Failure (MTBF) = (AT) / Number of Breakdown Events
It is calculated the same way for each resource and each reporting period. The grand total is not the arithmetic average of the individual totals, for the same reason it is not valid to average availability, utilisation and CHPP yield totals.
How Corvus rolls up to MTD or monthly numbers for PU and EA?
Process Utilisation is defined as the percentage of available time that the plant was performing its primary function. The definition of the time usage model shows that truck process utilisation formula is as below:
Availability is defined as the percentage of calendar time less Standby Time that plant was physically available for work. Availability is a measure of the time that plant and equipment is available to perform its intended function over a defined period:
