A nameplate list is usually the first electrical document available on a mine project, but adding the equipment kW does not determine generator capacity. Engineers need a schedule that shows operating combinations, starting duty, criticality and expansion.
Check whether this article fits your project
Teams planning a new mine, an expansion or replacement of an old power station across crushing, conveying, dewatering, ventilation, camp and safety loads.
Convert nameplate ratings, starting methods, operating combinations and restoration order into sizing evidence instead of reporting one total kW figure.
Produce an equipment schedule, starting sequence, critical-load classification and expansion list for genset, ATS, paralleling and distribution review.
A useful load list must answer four questions: which equipment must be powered, what runs together, when the largest starting step occurs, and how loads should be restored after an outage.
01
Classify production, safety and support loads first
Crushing, screening and conveying drive output; dewatering, tailings, ventilation, communications and fire systems may protect people or the mine; camp and workshop loads sustain operations. Classification establishes what must return immediately, what can wait and what can be shed.
- Production: crushers, screens, conveyors, mills and compressors
- Safety: dewatering, tailings, ventilation, fire systems and communications
- Support: camp, lighting, offices, stores and workshops
- Future: approved expansion equipment and planned feeders
02
Record motor starting method, not running kW alone
Two sites with the same running demand can impose very different transient duty. Direct-on-line, star-delta, soft starter and variable-frequency drive starting require different generator response. Record motor rating, voltage, starting method and whether starting is unloaded or under process material.
- Capture kW, efficiency, power factor and rated current
- Identify DOL, star-delta, soft starter or VFD
- Separate unloaded, loaded and blocked-start risk
- Mark unknown values for confirmation instead of guessing
03
Use operating scenarios and a timeline
Mine loads do not operate in one fixed combination. List normal production, maintenance, shift change, storm dewatering and outage restoration separately. A timeline reveals the true peak combination and the most demanding starting step.
- Normal production combination and continuous hours
- Alternative arrangement during equipment maintenance
- Storm, flooding or safety-event combination
- First, second and final restoration groups
04
Site conditions change usable generator output
Provide voltage, frequency, altitude, ambient temperature, dust, ventilation, cable distance and existing bus data. Altitude derating, voltage drop and cooling limits can prevent a nameplate rating from being delivered continuously at site.
- Voltage, frequency, phases and earthing arrangement
- Altitude, maximum temperature, dust and rainy-season conditions
- Cable distance to the main distribution point
- Existing transformers, busbars, breakers and protection
05
Turn the sizing decision into traceable documents
The result should not be one recommended rating. Engineering should state steady load, largest starting step, reserve, derating assumptions and expansion boundary, with each conclusion traceable to the equipment schedule.
- Steady demand and expected load factor
- Largest starting step and acceptable voltage dip
- Temperature and altitude assumptions
- Expansion margin and triggers for a new review
Fields every mine load schedule should retain
| Equipment identity | Area, equipment name, tag and duty |
|---|---|
| Electrical data | kW, kVA, voltage, phases, current and power factor |
| Starting data | Starting method, multiplier, unloaded or loaded start |
| Operating relationship | Coincidence, interlocks and daily operating hours |
| Criticality | Immediate, delayed or shed during emergency |
| Expansion status | Existing, purchased, approved or allowance only |
Three common mistakes
Reporting installed kW only
Installed capacity does not show coincidence or sequence and can cause oversizing or inadequate starting performance.
Assuming every load starts together
This creates an unrealistic rating and hides the restoration sequence that should be engineered.
Ignoring expansion and distribution limits
Generator reserve does not prove that busbars, cables, switchgear and fuel systems can accept expansion.
Check the package before engineering review
- The equipment list has a source and revision date
- Starting methods for critical motors are confirmed
- Normal, emergency and restoration scenarios are separated
- Altitude, temperature and cable distance are provided
- Unknown data is visibly marked for confirmation
- Expansion loads are separated from existing loads