1. On-site performance
Typical symptoms on site
- As soon as the crusher, mill, water pump or air compressor is started, the generator speed will drop and the voltage will drop significantly.
- A single piece of equipment can be turned on, but multiple pieces of equipment will trip if they are turned on at the same time according to the production rhythm.
- Onsite personnel can only shut down the camp, workshop or part of the conveyor belt before trying to start the main equipment.
- The power quoted by the supplier seems to be sufficient, but it becomes unstable when the startup sequence changes during trial production.
2. Risk causes
Root cause in the power-system design
The mining load is not just about the operating power. The starting of large motors, motor control methods, starting of conveyor belt materials, and changes in water pump lift will all affect the instantaneous endurance of the generator.
If the review only adds up equipment nameplate power without confirming which equipment starts at the same time, which equipment must run continuously and which loads can start later, generator-set capacity and distribution protection can be overwhelmed by on-site startup impact.
The expansion site will also encounter a problem: old equipment, new equipment, and temporary equipment are mixed together, and the original power distribution and cables are not recalculated according to the new production rhythm.
3. Scope of influence
Production, fuel, maintenance, safety and environmental risks all grow
- Trial production failed repeatedly, and the crushing, screening, pumping stations and conveying systems could not form a stable rhythm.
- After each trip, it must be checked, reset, and restarted. The entire shift's output and management time will be lost.
- If the generator operates under inappropriate load impact for a long time, fuel consumption, wear and failure probability will increase.
- A routine electrical problem becomes a safety risk if dewatering or ventilation loads are disconnected at the same time.
4. How to avoid before construction
What to confirm before procurement or expansion
- Don’t just ask “how many kW are needed?” First, list the main equipment list, startup method, simultaneous operation relationship and future expansion equipment.
- Confirm which crushers, pumps, air compressors, conveyor belts, welders, camps and workshops must run together and which ones can be started in batches.
- Reserve starting margin, paralleling possibility, low-voltage distribution, and cable capacity in the plan. Do not look only at the generator set price.
- Before trial production, write the startup sequence into the commissioning plan to avoid temporarily switching equipment on-site based on experience.
5. On-site confirmation information
Site information needed for an engineering review
- List of main equipment and photos of nameplates, especially crushers, water pumps, air compressors, mills, and conveyor belts.
- The starting method of each device, whether it is soft start, frequency conversion or direct start.
- Equipment planned to operate simultaneously, operating hours per day and equipment for future expansion.
- Site voltage, frequency, altitude, temperature, and existing generator or grid conditions.
