The standard SI unit of time is the second (s), defined in quantum metrology via the unperturbed ground-state hyperfine transition frequency of the cesium-133 atom (\(\Delta
u_{Cs} = 9,192,631,770 \text{ Hz}\)). The minute (min) is an accepted non-SI unit defined as exactly 60 SI seconds. The week (wk) is a customary time unit consisting of exactly 7 solar days, 168 hours, or 10,080 minutes (\(1 \text{ wk} = 7 \times 24 \times 60 \text{ min} = 10080 \text{ min}\)).
In process engineering, production planning, catalyst management, and plant turnarounds are framed in weeks, whereas dynamic process modeling, Distributed Control Systems (DCS), and equipment residence times operate on minute or second scales. Converting weeks to minutes is crucial when mapping high-level operational schedules to real-time control algorithms and continuous processing metrics.
Maintenance & Turnaround Planning: Equipment Preventative Maintenance (PM) intervals are often scheduled in weeks. However, process availability, mean time between failures (MTBF), and Overall Equipment Effectiveness (OEE) require precise time tracking in minutes: \( t_{\text{min}} = t_{\text{wk}} \times 10080 \).
DCS and PLC Data Registers: Automated logic controllers (PLCs) store timer registers in milliseconds, seconds, or minutes. Converting a 2-week campaign window to minutes (20,160 min) prevents integer overflow errors in system timers that use 16-bit or 32-bit registers.
Operating Time vs. Calendar Time: Engineers must distinguish calendar weeks from effective operating weeks. A calendar week contains 10,080 minutes, but if a process unit operates on an 80% capacity utilization factor or planned maintenance window, effective process time must be adjusted: \( t_{\text{operating}} = t_{\text{wk}} \times 10080 \times \eta_{\text{availability}} \).
Week to Minute Conversion Reference Table
Week (wk)
Minute (min)
0.1
1008
0.5
5040
1.0
10080
2.0
20160
5.0
50400
10.0
100800
20.0
201600
50.0
504000
100.0
1.0080e+06
500.0
5.0400e+06
1000.0
1.0080e+07
To convert a 10-week catalyst operating campaign into elapsed runtime in minutes, multiply the duration in weeks by the exact factor of 10,080:
Overall Equipment Effectiveness (OEE) relies on accurate runtime tracking. A 1-week calendar period provides a base denominator of 10,080 available minutes. Unplanned downtime logged in minutes (e.g., 504 minutes) directly yields operational availability: \( \frac{10080 - 504}{10080} = 95\% \). Converting all schedule terms to minutes eliminates mixing time units across different logging tools.
Yes. Industrial PLCs often store timer values in 16-bit or 32-bit integers representing milliseconds or seconds. While 1 week is 10,080 minutes, converting 1 week directly to milliseconds yields \(604,800,000 \text{ ms}\), which exceeds a standard 16-bit signed integer limit (32,767). Using minute-based registers (10,080 min) fits easily into standard data types without overflow risk.
"On fait la science avec des faits, comme on fait une maison avec des pierres ; mais une accumulation de faits n'est pas plus une science qu'un tas de pierres n'est une maison." "Science is built up of facts, as a house is built of stones; but an accumulation of facts is no more a science than a heap of stones is a house." — Henri Poincaré (French Mathematician, Theoretical Physicist & Mining Engineer)