Parameter Category Specification Parent System Designed for integration into ABB UniGear ZS1 or similar MV switchgear panels. Input Power Supply • Voltage: Typically accepts a 3-phase + Neutral input from an external LV source. Common ratings: 400V AC, 50/60 Hz or 480V AC, 60 Hz. • Connection: Via terminal blocks or plug-in connector at the rear of the unit. Core Components (Typical) 1. Main LV Incoming Switch/Isolator: A miniature circuit breaker (MCB) or molded case switch for isolation and protection of the entire CSU. 2. Control Transformer(s): Steps down voltage to standard control voltages (e.g., 230V AC, 120V AC, 110V AC, 24V DC). 3. Distribution & Protection: Multiple outgoing circuits protected by MCBs or fuses for: - Heating & Dehumidification (H) - Lighting (L) - Socket Outlets (S) - Protection & Control Relays (Prot) - Motor Operating Mechanisms (for circuit breakers/disconnectors) 4. Terminal Blocks: For connecting external field wiring to the distributed services. Output Circuits (Typical) • AC Power Outlets: 1-Phase, 230V (e.g., for soldering iron, test equipment). • DC Power Supply: 24V DC or 48V DC for protection relays, PLCs, and electronic devices. • Heating Circuit: 230V AC for space heater to prevent condensation. • Lighting Circuit: 230V AC or 120V AC for internal panel lighting. • Auxiliary Supply: For spring charging motors, indicator lamps. Mounting Mounts on a dedicated draw-out chassis or fixed rails inside a standard UniGear compartment (often below the relay compartment). Connection Plug-in or fixed wiring to the MV panel's internal wiring harness. Safety Features • Clear segregation of circuits. • Individual protection for each outgoing circuit. • Door interlock possible for the main isolator. • Insulated covers and shrouds. Physical Dimensions Compact, designed to fit within a standard UniGear module width (e.g., 350mm, 400mm, 500mm). Benefits • Standardization: Ensures consistent auxiliary power design across all panels. • Safety: Centralized, properly protected LV distribution reduces wiring errors and hazards. • Maintenance: Entire unit can be easily accessed, tested, or replaced. • Documentation: Supplied with clear wiring diagrams.