This is a type of Medium Voltage (MV) Switchgear designed for 3.6kV to 12kV power distribution systems. It is commonly referred to as a "Ring Main Unit" (RMU) in international markets, though this specific description ("Box-type Fixed") typically points to an Air Insulated (AIS) modular unit rather than a fully gas-sealed (GIS) tank. It serves as the critical "node" in a ring network, allowing power to be distributed to multiple users (e.g., a transformer or a building) while maintaining the ability to isolate faults without shutting down the entire grid.

The RVV is a highly flexible, double-insulated cable designed for applications requiring frequent movement, vibration resistance, or easy routing. The "R" stands for Flexible (软), indicating that the conductor consists of many fine, oxygen-free copper wires bundled together (Class 5 conductor) rather than a single solid core. With a 16mm² cross-section, this cable is heavy-duty. It is primarily used for: Mobile Power Supply: Connecting portable industrial machinery or large-scale medical equipment. Internal Cabinet Wiring: Powering large control panels where space is tight and cables must be routed around sharp corners. Secondary Distribution: Linking power sources to equipment in environments where the cable needs moderate mechanical protection (provided by the outer PVC jacket).

The ZA-BVV is a heavy-duty, double-insulated copper wire designed for high-security internal power distribution. The "ZA" prefix denotes Class A Flame Retardancy, the highest rating for standard flame-retardant cables, ensuring that the cable will not spread fire even when installed in dense bundles. Unlike standard BV (single layer insulation), the BVV features both a PVC insulation layer and an additional PVC outer sheath. This "jacketed" design provides extra moisture resistance and mechanical protection, allowing the cable to be used in damp environments or directly surface-mounted without additional conduit in certain industrial applications. At 300mm², this is an exceptionally large gauge for a 300/500V rated wire, typically used as a main power lead-in or grounding busbar in large-scale electrical cabinets and substations where high current capacity and maximum fire safety are mandatory.

The BLV is a single-core, Aluminum Conductor, PVC insulated wire. It belongs to the common "fixed wiring" or "building wire" category and serves as the economical alternative to the copper-core BV wire. Because aluminum is significantly lighter and less expensive than copper, BLV is widely used in cost-sensitive construction projects, rural power upgrades, and internal wiring for large industrial equipment. It is designed for fixed installation within power installations, household appliances, instruments, and telecommunications equipment with AC voltages up to 450/750V.