QHSQ Dual Power Automatic Transfer Switch (ATS) Distribution Cabinet
QHSQ dual-power distribution cabinets are suitable for power plants, industrial and mining enterprises, and commercial facilities requiring reliable dual-power supply switching. They are designed for three-phase three-wire, three-phase four-wire, and three-phase five-wire systems with AC voltage up to 500V and rated frequency of 50Hz/60Hz, used for power and lighting distribution where supply continuity is critical.
The QHSQ series integrates an automatic transfer switch (ATS) controller and switching mechanism within a standardized distribution enclosure, providing automatic switching between primary (mains/normal) and secondary (standby/emergency) power sources. In the event of mains power failure, voltage deviation beyond preset thresholds, or phase loss, the ATS controller initiates automatic transfer to the standby source within a configurable time delay (typically 0.1–5 seconds), ensuring uninterrupted power supply to critical loads.
The ATS dual-power distribution box is designed for indoor wall-mounted installation with front-panel access for operation, monitoring, and maintenance.
Technical Specifications
| Item | Specification |
|---|---|
| Rated Voltage | AC 400V / 415V (500V max.) |
| Rated Frequency | 50Hz / 60Hz |
| Rated Current | 63A / 100A / 160A / 250A / 400A / 630A (selectable by model) |
| Rated Short-time Withstand Current (Icw) | 10kA / 25kA (1s) |
| Rated Peak Withstand Current (Ipk) | 25kA / 52.5kA |
| Power System Configuration | Three-phase three-wire / Three-phase four-wire / Three-phase five-wire |
| Transfer Type | Automatic (self-acting) / Remote / Manual (maintenance bypass) |
| Transfer Time (Mains to Standby) | 0.1 – 5.0 seconds (adjustable via controller) |
| Return Time (Standby to Mains) | 0 – 30 minutes (adjustable, with return voltage detection) |
| Detection Parameters | Three-phase voltage, phase loss, phase sequence, overvoltage, undervoltage, frequency deviation |
| Switching Device | MCCB-based or contactor-based ATS mechanism |
| Electrical Durability | ≥ 6,000 operations (at rated current) |
| Mechanical Durability | ≥ 10,000 operations |
| Degree of Protection | IP30 / IP40 (indoor enclosure) |
| Installation Type | Indoor, wall-mounted, front-panel access |
| Enclosure Material | Cold-rolled steel with epoxy powder coating |
| Standards | GB/T 14048.11, IEC 60947-6-1 |
Key Features
- Automatic Dual-Power Switching: The integrated intelligent ATS controller continuously monitors both power sources — in the event of mains failure, undervoltage, overvoltage, or phase loss beyond preset thresholds, the controller initiates automatic transfer to the standby source within a user-adjustable time delay (0.1–5 seconds), restoring power to critical loads without manual intervention
- Reliable Power Supply Continuity: Ensures uninterrupted power to critical loads including safety systems, emergency lighting, fire pumps, communication equipment, life safety systems, and process control systems — essential for applications where power interruption poses safety risks, causes production losses, or damages sensitive equipment
- Configurable Operating Modes: Supports automatic mode (self-acting transfer based on source monitoring), remote control mode (transfer command via external signal), and manual mode (maintenance bypass operation) — providing operational flexibility for different application scenarios and maintenance requirements
- Configurable Return Function: After transfer to standby source, the controller monitors mains voltage recovery — once mains voltage returns to within acceptable thresholds for a user-adjustable stabilization period (0–30 minutes), the controller automatically transfers back to the primary source, ensuring stable mains restoration before reconnection
- Compact Wall-Mounted Design: Designed for indoor wall mounting with front-panel access — all operating controls, status indicators, and metering displays are accessible from the front, minimizing footprint and allowing installation in space-constrained distribution rooms
- Clear Status Indication: Front panel provides visual indication of active power source, source availability status, transfer position, and system normal/alarm conditions via LED indicators and optional digital display — enabling at-a-glance system status assessment by facility operators
- Versatile System Compatibility: Compatible with three-phase three-wire, three-phase four-wire, and three-phase five-wire (TN-S, TN-C, TN-C-S, TT) power distribution systems — suitable for a wide range of international low voltage distribution network configurations
- Protection Coordination: Incoming and outgoing circuits are protected by MCCBs with coordinated protective device settings, ensuring selective fault isolation while maintaining power supply to unaffected circuits
Applications
- Power plants — auxiliary power supply changeover and emergency power systems
- Industrial and mining enterprises — process-critical power supply continuity
- Commercial buildings — life safety systems, emergency lighting, and fire pumps
- Hospitals — critical care power supply and medical equipment backup
- Data centers and telecommunications — uninterruptible power distribution
- Airports and railway stations — essential services and signaling power supply
- Water and wastewater treatment — continuous process power supply
- Oil and gas facilities — emergency shutdown (ESD) and safety system power