1. On-site performance
Typical symptoms on site
- When the crushing line starts, camp lighting, office communications, and maintenance workshops can also be affected.
- After the pumping station fails or the line trips, it is not clear which part should be restored first.
- There are more and more temporary cables stretched, and production, drainage, dormitories, canteens and warehouses share the same set of protection.
- After a power outage, the switching sequence has to be decided manually, so recovery time is difficult to control.
2. Risk causes
Root cause in the power-system design
In the early days of mine construction, temporary power supplies were often used to run the site first, and then equipment was added continuously, without re-dividing production load, security load and living load.
When production, drainage, camps and maintenance workshops share a power zone, any overload, short circuit, misoperation or generator failure may affect other areas.
There is no load priority, and there is no clear power distribution zone. During a power outage, the site can only decide based on experience to protect production, drainage, or camp first.
3. Scope of influence
Production, fuel, maintenance, safety and environmental risks all grow
- When the production line stopped, the maintenance workshop also had no power, and the recovery speed was even slower.
- Drainage pumps, tailings pumps or communication equipment are towed away together, which will increase safety and environmental risks.
- Camp lighting, canteens, communications and security are affected, and the pressure on mine site management increases.
- Every failure will become a mine-wide investigation, and the downtime will be extended.
4. How to avoid before construction
What to confirm before procurement or expansion
- The electricity consumption in the mine site is first divided into several categories: production, drainage/tailings/safety, maintenance workshops, camp offices and temporary construction.
- Clear which loads cannot be stopped for even one minute, which loads can be restored with a delay, and which loads can be temporarily shut down when the generator is insufficient.
- Set up independent circuits, independent protection and clear switching logic for critical loads, and do not rely on temporary cable splicing for a long time.
- Before expansion, review whether the low-voltage cabinet, cables, circuit breakers, ATS and generator capacity can still keep up with the new load zone.
5. On-site confirmation information
Site information needed for an engineering review
- Plane or simple hand-drawn layout of the mine site, marking the crushing line, pumping station, tailings, workshop, camp and office area.
- The main equipment in each area, whether it must operate continuously, and the acceptable recovery time after a power outage.
- Photos of existing distribution cabinets, cable routing, switch protection and generator access points.
- Records of trips, outages, manual switching and restoration times that have occurred in the past.
