Isolation Type Automatic Transfer Switch

The LDQ5 series automatic transfer switch is designed for dual power supply systems that require reliable switching between commonly used power and standby power. When the normal supply has undervoltage, phase loss, or another abnormal condition, the switch can transfer the load to the backup source and return when the normal source is restored.

As one of the PC Class Automatic Transfer Switches for low-voltage distribution, the LDQ5 series uses a pre-stored energy opening and closing structure, single-throw double-row contacts, and electrical plus mechanical interlocking to support stable, safe, and efficient power transfer in critical facilities.

• Designed PC-grade ATSE: Meets GB/T14048.11 and IEC/EN60947-6-1 requirements for automatic transfer switching equipment.
• AC-33B application category: Suitable for demanding load switching applications in low-voltage power systems.
• Fast transfer action: Switch action time is 0.4s-0.5s to support quick source changeover.
• Reliable contact structure: Single-throw double-row contacts, large opening distance, and strong contact pressure help improve isolation and conductivity.
• Three-phase synchronization: The three phases and N phase are driven on the same axis, keeping synchronization deviation within 10ms.
• Fire protection and feedback support: Three-section structure design can provide fire protection and fire feedback functions according to user needs.
• Compact modular design: Small size, light weight, modular structure, plastic shell insulation, and no grounding requirement help simplify installation.

This transfer switch is suitable for systems where outage time should be reduced and the load must be supplied by either normal power or backup power.

• Hospitals, banks, airports, docks, and hotels
• Residential communities and high-rise buildings
• Post and telecommunications facilities
• Fire protection systems and emergency power distribution
• TV stations, military facilities, and shopping malls
• Three-phase four-wire grid supply systems using common and backup power sources

• The operating mechanism uses pre-stored energy opening and closing to support quick switching action.
• The switch includes closing indicator lights for two power supplies and mechanical contact-position indication.
• Three working states can be controlled manually: commonly used power, standby power, and dual-split/off position.
• Manual mode can be entered through the manual/automatic door, allowing operation during maintenance.
• The two-way switch is protected by electrical and mechanical interlocking so both sources cannot close at the same time.

• Ambient temperature should not exceed +40°C, should not be lower than -5°C, and the 24-hour average should not exceed +35°C.
• Installation altitude should not exceed 2000m.
• Relative humidity should not exceed 50% at +40°C; higher humidity is allowed at lower temperature with condensation considered.
• The switch can be installed vertically or horizontally in control cabinets and electrical cabinets.
• Recommended installation environment should avoid severe vibration, shock, corrosive gas, excessive dust, high humidity, and direct outdoor exposure.

When selecting the correct model, confirm the rated current, shell frame current, pole number, normal and standby power type, installation direction, wiring space, fire feedback requirement, and whether generator start-stop or four-pole switching is required. For backup generator systems or neutral-line potential differences, a four-pole product is recommended.

Need help choosing from the PC Class Automatic Transfer Switches range? Send the rated current, pole configuration, working voltage, application scenario, normal/standby power type, and order quantity. Our team can provide model guidance, technical data, wiring support, and quotation options.