GWPS-AC Microprocessor-Based AC Power Supply Panel

Product Description

• The GWPS-AC is designed for the incoming supply, transfer, distribution and monitoring of AC auxiliary power. It can be configured with a single incomer, dual incomers, a single busbar or a sectionalized single-busbar arrangement.
• If the normal source experiences loss of voltage, undervoltage, overvoltage, phase loss or abnormal frequency, the controller transfers the connected loads to the alternative source after the configured time delay and interlocking conditions have been satisfied. When the normal source returns to healthy conditions, the system can automatically retransfer, wait for manual retransfer or continue operating from the alternative source.
• The industrial touchscreen uses a dynamic single-line diagram to display the operating status of the incomers, busbar, switching devices and outgoing feeders. It also displays voltage, current, frequency, active power, reactive power, power factor and energy measurements. The system provides alarm annunciation, event logging, parameter setting and role-based access control.
• Through RS-485 or Ethernet communication, the panel can be integrated with a SCADA or substation automation system for the transmission of measurements, switching device status and alarm information. Authorized remote switching control can also be provided when electrically operated switching devices, control circuits and the necessary safety interlocks are installed.

System Components and Configuration

• Typical arrangements include a single incomer with multiple outgoing feeders, dual incomers with normal-to-alternative source transfer, dual incomers operating as mutual backup sources, and dual incomers with a sectionalized busbar and a bus-section switching device. The final arrangement is determined by the project single-line diagram, load schedule and technical requirements.

Product Functions

•  Electrical measurements: Provides real-time measurement of three-phase voltage, current, frequency, active power, reactive power, power factor and energy.
•  Dual-source transfer: Continuously monitors both incoming sources and transfers the connected loads to the alternative source when the normal source becomes abnormal, subject to the configured time delays and interlocking logic. Automatic and manual retransfer are supported. Conventional ATSE, contactors or circuit breakers normally cause a brief supply interruption during transfer. Loads that cannot tolerate an interruption should be supplied through a UPS, emergency power supply system or static transfer switch.
•  Alarm annunciation: Provides alarms for overvoltage, undervoltage, loss of voltage, phase loss, incorrect phase sequence, abnormal frequency, switching device failure and communication failure. Alarms can be indicated through the touchscreen, indicator lamps, an audible annunciator, dry contacts or communication interfaces.
•  Outgoing feeder management: Displays the position and fault status of outgoing feeder switching devices. When feeder monitoring modules are installed, feeder current, energy and switching status can also be monitored.
•  Graphical display: Uses a dynamic single-line diagram to display the operating status of the incoming sources, busbars, bus-section switching device and outgoing feeders.
•  Event logging and access control: Records source abnormalities, switching operations, alarms and parameter changes. Role-based access control is used to manage parameter settings and switching operations.
•  Communication and remote monitoring: Provides RS-485 and Ethernet interfaces and supports Modbus RTU, IEC 60870-5-103 and IEC 61850 for integration with SCADA and substation automation systems. IEC 61850 functionality requires an appropriate communication module, data model and engineering files. Remote control requires electrically operated switching devices, control circuits and the necessary safety interlocks.
•  Safety interlocking: Supports electrical, mechanical or logic interlocking between the incomer switching devices and between the incomers and the bus-section switching device, preventing unintended source paralleling and inadvertent switching operations.

Technical Specifications

• The following values represent typical configurations. Final specifications are subject to the project requirements.

Design and Applicable Standards

The GWPS-AC is designed, manufactured and verified in accordance with the applicable requirements for low-voltage switchgear and controlgear assemblies. The principal applicable standards include:

• GB/T 7251.1—2023;
• GB/T 7251.2—2023;
• IEC 61439-1:2020;
• IEC 61439-2:2020;
• GB/T 14048 series / IEC 60947 series;
• GB/T 4208 / IEC 60529;
• GB/T 17626 series / IEC 61000-4 series.

The applicable standards, verification requirements, test items and technical specifications for each project shall be defined in the contract documents and project technical specification.

Applications

• Power plants: AC auxiliary power distribution for protection and control equipment, communication devices, instrumentation and auxiliary lighting.
• Substations: Transfer, distribution and monitoring of station AC auxiliary power.
• Renewable energy facilities: Solar power plants, wind farms, battery energy storage facilities and associated substations.
• Switching stations and distribution rooms: AC power for distribution terminal units (DTUs), feeder terminal units (FTUs), monitoring equipment, communication devices and lighting.
• Industrial facilities: Power distribution systems in the steel, chemical, oil and gas, mining, cement and general manufacturing industries.
• Public infrastructure: Rail transit systems, airports, ports, water treatment facilities, hospitals and data centers.
• Emergency lighting: Source transfer and outgoing distribution for emergency lighting systems supplied by dual utility sources, generating sets, a UPS or an emergency power supply system.

The GWPS-AC does not incorporate energy storage. The available backup duration is determined by the external alternative source or energy storage system. Loads that cannot tolerate a brief supply interruption should be supplied through a UPS, emergency power supply system or another suitable uninterruptible power source.

GoWatron offers customized engineering and fully assembled panels based on the project single-line diagram, load capacity, outgoing feeder requirements, communication protocols and enclosure dimensions.