Recommended Control Cabinet Configuration for 200TPD Ore Processing Plant

Recommended Control Cabinet Configuration for 200TPD Ore Processing Plant 

1. Core Control Unit

PLC Selection: No need for large redundant systems. Mainstream choices include Siemens S7-1200 or a small S7-1500 configuration. Domestic PLCs with mining industry track records (e.g., Hollysys LK series) are also viable. This level handles the logic interlocking and analog loops for a 200 t/d line.

HMI: One 10–15 inch touch screen in the local control room for process monitoring, parameter setting, and alarm viewing. A separate industrial PC is unnecessary unless long-term historical data logging is required.

2. Drive & Actuator Units

Soft Starters: Large motors (jaw crusher, cone crusher, ball mill — typically tens to hundreds of kW) should use soft starters to reduce starting current surge.

VFDs: Equipment requiring flow adjustment (disc/belt feeder, reagent pump) should use VFDs with Modbus or Profibus-DP communication to the PLC.

Intermediate Relays: All DO outputs must be isolated through 24V DC intermediate relays before driving contactors or soft starters, protecting the PLC output modules.

3. Power & Protection

Configure AC220V/DC24V switching power supplies sized at 1.5× the total power consumption of I/O modules and relays.

Install an isolation transformer or UPS ahead of the PLC power supply to prevent voltage fluctuations or brief power loss from restarting the PLC.

Analog signals (density, flow, level) should pass through signal isolators and convert to 4–20mA before entering the PLC to filter field interference.

Special Considerations for 200 t/d Scale

1. Interlocking Logic Is the Priority, Not Network Architecture
A 200 t/d plant typically has few operators (possibly only a handful). The PLC's core task is ensuring reverse-flow start and forward-flow stop interlocking. For example: the ball mill cannot start until the classifier is running; if the flotation feed pump stops, the flotation cells should shut down automatically. A single mid-range PLC can reliably implement these logic sequences — no complex DCS network is needed.

2. Environmental Protection Is Essential
Crushing and grinding workshops at 200 t/d plants still generate significant dust. If the cabinet is installed on-site, the protection rating should be at least IP54; near a crusher, IP55 with a cabinet fan or small air conditioner is recommended. Cabinet steel plate thickness should be no less than 1.5–2mm, and door seals must be intact.

3. Reagent Control Should Be Practical
Small flotation lines usually have few reagent addition points. A simple electromagnetic flowmeter + VFD reagent pump controlled by the PLC for proportional dosing based on feed rate is sufficient. Complex automatic reagent preparation systems (e.g., 95°C hot water mixing, multi-stage dilution) are better suited for large plants with many reagent types and dosing points.

4. Grounding & Wiring
Strong power (380V) and weak signal (24V, 4–20mA) cables must be routed in separate trays or separate sides of the cabinet. Analog signal cables should be shielded twisted pair, with the shield grounded at the PLC end only. Install an independent grounding copper bar at the bottom of the cabinet; grounding resistance must meet code requirements.