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1. General Provisions

1.1 Scope of Application

This chapter specifies the technical requirements for the supply, installation, testing, trial operation, and normal commissioning of complete diesel generator sets for data centers. It covers the entire process of technical standards, including the generator set itself, auxiliary systems, control systems, and environmental protection engineering. It is applicable to the design, procurement, construction, and acceptance of emergency diesel generator sets for data centers.

1.2 Equipment Composition

The diesel generator set system must include, but is not limited to, the following core components, each of which must meet the high reliability and stability power supply requirements of the data center:

Complete Diesel Engine/Generator Set: Includes basic components such as radiators, shock absorbers, and foundation bolts, ensuring stable operation and vibration compliance with specifications.

Speed ​​Control System: Employs an electronic full-speed speed control system to achieve precise speed control and ensure stable output frequency.

Eco-friendly Data Center System: Includes complete smoke extraction, noise reduction, and air intake devices, equipped with silencers, suspension systems, and thermal insulation materials, meeting environmental and noise control standards.

Fuel Delivery System: Covers outdoor fuel tanks, trench excavation and treatment, fuel delivery system protection accessories, daily fuel tank delivery pipes, valves, and fuel pump equipment, ensuring a safe and reliable fuel supply.

Control System: Includes control cabinets, control panels, and auxiliary control equipment, supporting manual and automatic operation modes.

Monitoring System Interface: Provides a unified interface for environmental monitoring and power monitoring systems, enabling real-time monitoring and remote control of the unit’s operating status.

Grounding System: Equipped with a grounding resistor cabinet to ensure system electrical safety.

Starting System: Employs a DC starting system with two sets of batteries to ensure rapid unit startup.

Output Equipment: 10KV high-voltage parallel output cabinet to meet high-voltage grid-connected power supply requirements.

1.3 Starting and Load Requirements

The generator set must be equipped with both manual and fully automatic start-up facilities. In the event of a main power failure or deviations in parameters such as voltage and frequency exceeding acceptable limits, it must start up and load the designed emergency load within 60 seconds to ensure uninterrupted power supply to the data center’s core equipment.

The automatic start-up process should include power failure detection, delayed start-up, unit self-test, voltage and frequency establishment, and load switching. The manual start-up mode must have emergency operation priority.

1.4 Capacity Design Principles

The power generation capacity must meet the load requirements of the data center under the most unfavorable conditions. In addition to calculations based on the load table, the following key factors must be considered to ensure long-term stable operation and a certain degree of redundancy:

Environmental Impact: Factors such as ambient temperature and altitude can reduce the rated output factor. Capacity adjustments must be made based on the actual environmental parameters of the data center.

Impact Load: The inrush current generated when data center UPS, air conditioning, and other equipment starts up requires the unit to withstand short-term impact loads. An impact factor of 1.2-1.5 should be considered.

Transient Voltage: Transient voltage drops caused by load fluctuations require a rapid response from the unit’s voltage regulation system to ensure voltage stability within the allowable range.

Regenerative Power: Regenerative power generated during the operation of some equipment requires the unit to absorb or suppress regenerative power to prevent damage.

Rectifying Load: Harmonic currents generated by numerous rectifier devices in the data center require the unit to have harmonic interference immunity to reduce the impact of harmonics on the quality of output power.

Three-phase imbalance: The three-phase imbalance problem caused by uneven load distribution among phases. The unit must be able to operate normally under the condition that the three-phase load imbalance is ≤15%.

1.5 Quality Assurance Standards

The manufacture of all components and auxiliary equipment must meet applicability requirements; material selection, processing technology, and assembly precision must all comply with relevant national and industry standards.

The generator set must comply with fire department and other relevant regulatory requirements, ensuring it passes fire safety and environmental protection inspections and possesses legal operating qualifications.

The supplier must provide all necessary equipment, accessories, and technical support to guarantee satisfactory operation of the generator set under different climatic conditions in the data center (such as high temperatures in summer and low temperatures in winter).

The performance level of the diesel generator set should not be lower than G3, meeting the high requirements of the data center for power supply reliability and voltage/frequency stability.

The power rating must meet the following standards:

10kV high-voltage diesel generator sets: must meet the main power requirement of 2000kW or above as defined in industry standard YD/T 2888-2015 4.5 Engine Set Power Rating, or the basic power PRP of 2000kW or above as defined in national standard GB/T 2820.5 Power Rating Category;

0.4kV low-voltage diesel generator sets: must meet the main power requirement of 1000kW or above as defined in industry standard YD/T 2888-2015 4.5 Engine Set Power Rating.

1.6 Delivery Document Requirements

At each stage of the project, the supplier must submit the following detailed documents as required to ensure controllable project progress and quality:

Equipment and Component List: Includes manufacturer data, environmental protection material parameters, smoke suppression material performance, and fuel supply system component specifications;

Construction Drawings: Detailed coordination diagram of generator room equipment layout, fuel tank room layout diagram, and outdoor fuel tank diagram, along with calculations, piping dimensions, structural details, and installation specifications for the engine exhaust system, fuel supply system, and cooling system;

Electrical Drawings: Electrical control circuit diagram, clearly specifying the internal and external wiring of the generator control panel and the terminal numbers of external device cable terminals;

Technical Documents: Detailed data on battery capacity calculations, equipment weight list, and requirements for building structure load-bearing capacity and space;

Testing Documents: Generator set testing procedures, test content, report forms, and testing recommendations, ensuring that testing covers all functions and performance indicators of the generator set.

2. Generator Manufacturing and Design Technical Parameters

2.1 Basic Design Parameters

The manufacturing and design of diesel generator sets must comply with national standards and specifications, and their core parameters must meet the operational requirements of the data center, as detailed in the table below:

Parameter Category

10kV High Voltage Unit

0.4kV Low Voltage Unit

General Requirements

Rated Output Voltage 10kV 0.4kV Voltage regulation accuracy: ≤±2.5% from no-load to full-load steady state
Rated Frequency 50Hz 50Hz Frequency regulation range: ±5% (manually adjustable), steady-state frequency deviation ≤±0.5Hz
Insulation Class Class F Class H Insulation materials should have temperature resistance and moisture resistance, meeting long-term operation aging requirements
Protection Class IP21 IP21 For indoor use, with dust and spray water protection capabilities. The cabinet protection complies with the IP21 standard
Grounding Method Neutral point grounded by resistance Neutral point grounded by resistance The grounding resistance value needs to be calculated and determined according to system parameters to ensure reliable grounding protection
Fuel Type Diesel suitable for the installation site environment Diesel suitable for the installation site environment Diesel grade should be selected according to the local climate environment to ensure reliable startup in winter
Installation Form Diesel engine and generator installed on a common base Diesel engine and generator installed on a common base The base should have sufficient rigidity to reduce the transmission of engine operating vibration
Anti-interference Requirements Equipped with anti-radio interference devices Equipped with anti-radio interference devices Comply with national regulations on electromagnetic compatibility to avoid interference with data center equipment
Safety Protection All external moving parts are sealed or equipped with protective devices, and overheated surfaces
are protected
All external moving parts are sealed or equipped with protective devices, and overheated surfaces
are protected
Protective equipment should have sufficient strength to prevent safety accidents caused by accidental contact
Appearance Coating Black metal anti-rust primer, outer colored paint(to be confirmed by approval) Black metal anti-rust primer, outer colored paint (to be confirmed by approval) The coating should have oil resistance, temperature resistance, and anti-aging properties, with strong adhesion
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2.2 Engine Technical Parameters

As the power core of the generator set, the engine must possess high reliability, high stability, and low emissions. Specific technical parameters are required as follows:

Parameter Name

Technical Requirements

Fuel Adaptability Applicable to diesel fuel commonly available locally, adopting turbocharging method, with air as the cooling medium
Power Matching The output power of the engine should match the operating capacity of the generator to ensure no overload risk when the unit operates at full load
Rated Speed 1500 rpm, speed stability ≤±1%, ensuring stable frequency output of the generator
Displacement Requirement The engine displacement should not be less than 75L to ensure the engine has sufficient power reserve
Fuel Injection Method Electronically controlled injection (EFI) or high-pressure common rail type, with high injection precision and good fuel atomization effect to improve combustion efficiency
Emission Standard Should meet the third-stage requirements of GB20891-2014 “Emission Limits and Measurement Methods for Air Pollutants from Diesel Engines of Non-Road Mobile Machinery (China Stage III, IV)”. If not met, an exhaust gas treatment device (DPF soot purifier + SCR denitrification system) should be installed. At the same time, it should comply with Shenzhen local environmental emission standards
Cooling System Equipped with a water jacket heating device, controlled by a thermostat, to maintain the engine water jacket temperature at around 30°C (or as recommended by the manufacturer) to ensure the unit is easy to start in low-temperature environments
Lubrication System Adopts a closed pressure supply lubrication system, equipped with a positive displacement mechanical lubricating oil pump, lubricating oil cooler, filter, and oil level indicator. The lubricating oil should have good low-temperature fluidity and high-temperature stability
Intake System Includes an intake supercharger, air filter, and intake cooler. The air filter should be equipped with an automatic alarm device that issues an alarm signal when the filter element is clogged
Starting System Equipped with a 24-volt DC starting battery pack. The battery pack should provide three consecutive starting capabilities with 5-second intervals within 15 seconds without damaging the battery. It is equipped with an automatic charger with floating charge and fast recharging functions, and a battery low-voltage sensing component
Protection Function Has protection functions such as low lubricating oil pressure, high engine coolant temperature, low coolant level, engine overspeed, engine overload, and low oil level. The protection action is divided into two stages: the first stage issues light and sound warning signals, and the second stage (dangerous state) automatically shuts down
Status Indication Has status indications such as oil pressure, oil temperature, engine temperature, operating speed, tachometer, and battery charging current. The indication accuracy should meet relevant standards, facilitating operators to monitor the engine operating status in real-time
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2.3 Generator Technical Parameters

The generator must be matched with the engine torque characteristics to ensure that the output power quality meets the requirements of data center equipment. Specific technical parameters are as follows:

Parameter Name

Technical Requirements

Manufacturing Standard Designed and manufactured in accordance with the relevant chapters of national standard specifications to ensure reliable product quality
Structural Type Brushless type, equipped with an Automatic Voltage Regulator (AVR), featuring fast voltage regulation response speed and high stability
Rated Value Correction The rated power of the generator should be corrected according to the local temperature conditions of the data center machine room to ensure that the output power meets the requirements in high-temperature environments
Torque Matching The torque characteristics of the generator should match those of the engine to ensure that the engine power is fully utilized when the unit operates at full load without overload
Protection Class Complies with the IP21 protection class specified in national standard specifications, for indoor use, with dust and drip water protection capabilities
Heating Device Equipped with a heater controlled by an internal thermostat to prevent internal moisture of the generator and ensure the unit can be started at any time during long-term standby
Insulation Performance The insulation class meets the requirements of Class F for 10kV units and Class H for 0.4kV units. The insulation resistance is ≥100MΩ under normal temperature and humidity conditions (measured with a 500V megohmmeter)
Temperature Rise Limit Under rated load, the temperature rise of the stator winding (Class F insulation) ≤80K (measured by the resistance method), the temperature rise of the rotor winding ≤100K, and the temperature rise of the iron core ≤75K
Voltage Regulation The Automatic Voltage Regulator (AVR) should ensure that the terminal voltage deviation of the generator is ≤±2.5% from no-load to full-load stable state, the voltage transient adjustment rate is ≤±10%, and the recovery time is ≤0.5 seconds
Harmonic Content The total harmonic distortion (THD) of the generator output voltage is ≤5% under rated load to ensure that the power quality meets the requirements of precision equipment in the data center
Parallel Operation Capability Capable of parallel operation with other generator sets. During parallel operation, the requirements of frequency, voltage, and phase synchronization should be met, and the load distribution unevenness ≤±10%
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2.4 Cooling System Technical Parameters

The cooling system must ensure that the engine and generator can maintain normal operating temperature under various operating conditions. Specific technical parameters are as follows:

Component Name

Technical Requirements

Radiator Matching components to the engine include a drive fan, coolant pump, thermostat-controlled liquid-cooled exhaust pipe, intercooler, and coolant filter; the coolant filter must be corrosion-resistant and adaptable to local water quality conditions; the radiator’s heat dissipation area needs to be determined based on engine heat load calculations to ensure sufficient heat dissipation capacity.
Installation Method The radiator can be mounted on the common base of the generator set, or installed separately on approved dedicated brackets as shown in the diagram; the radiator must be equipped with a ventilation channel flange joint for easy connection of the ventilation channel.
Duct Requirements A short duct section must be installed between the radiator and the metal louvers. All ducts are made of galvanized sheet steel that conforms to national structural standards, and the inner wall of the duct is smooth to reduce airflow resistance.
Fan Performance The fan needs to have sufficient airflow and air pressure, and the airflow should still meet the heat dissipation requirements even after considering the additional resistance of airflow from the channels and louvers; the fan speed should be matched with the engine speed, and a flexible connection should be used to reduce vibration transmission.
Cooling Medium Corrosion inhibitors and antifreeze need to be added to the cooling system. The corrosion inhibitor must be compatible with the metal materials of the cooling system, and the antifreeze concentration must be determined based on the local minimum ambient temperature to ensure that it does not freeze in winter.
Temperature Control The cooling system uses a thermostat for control. The thermostat opening temperature is set according to the engine manufacturer’s recommended value, generally 82-88℃, to ensure that the engine operating temperature remains stable within the optimal range.
Pressure Requirement The cooling system is pressurized, and the pressure rating of the coolant tank cap must meet the engine requirements, typically 0.08-0.12 MPa, to increase the boiling point of the coolant and enhance heat dissipation.
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2.5 Technical parameters of vibration damping device

The vibration damping device must effectively reduce the transmission of vibration during unit operation to protect the building structure and surrounding equipment. Specific technical parameters are as follows:

Parameter Name

Technical Requirements

Type Adopt spring-type shock absorbers. The spring material is high-quality spring steel, with good elasticity and fatigue resistance.
Installation Position The shock absorbers are installed under the unit base plate or between the generator set and the base plate to ensure uniform force on the entire unit.
Vibration Damping Effect When the unit is running, the vibration acceleration transmitted to the concrete floor through the shock absorber is ≤0.1g (frequency 10-100Hz), meeting the requirements for building structure earthquake resistance and the operation of surrounding equipment.
Load-Bearing Capacity The rated load-bearing capacity of each shock absorber shall be calculated and determined according to the weight and force distribution of the unit, with a safety factor ≥1.5.
Natural Frequency The natural frequency of the shock absorber ≤5Hz to avoid resonance with the unit or building structure.
Service Life Under normal use conditions, the service life of the shock absorber is not less than 10 years, with no obvious elastic attenuation or damage during this period.
Installation Requirements The shock absorbers should be installed horizontally, with an error ≤1°, and the height difference between adjacent shock absorbers ≤2mm to ensure stable support of the unit.
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2.6 Technical parameters of the lubricating oil unit

The lubrication system provides lubrication for the normal operation of the engine and must have reliable oil supply, cooling, and filtration functions. Specific technical parameters are as follows:

Component Name

Technical Requirements

Lubricating Oil Storage Tank The volume should meet the lubricating oil consumption of the engine during 8-12 hours of full-load operation. The tank is made of steel plate, with anti-rust treatment on the inner wall, and equipped with an oil level indicator, oil filler port, and oil drain valve.
Booster Pump Adopt a positive displacement oil pump with stable oil supply pressure. The rated oil supply pressure is set according to the engine requirements, generally 0.3-0.6MPa. The oil supply flow should meet the requirements of each lubrication point of the engine.
Lubricating Oil Cooler Adopt a shell-and-tube or plate-type cooler, with air or cooling water as the cooling medium. The cooling capacity should ensure that the lubricating oil temperature is controlled within the range of 60-90°C during full-load operation.
Filter Equipped with a coarse filter and a fine filter. The filtration precision of the fine filter is ≤10μm to ensure the cleanliness of the lubricating oil. The fine filter should be equipped with a clogging alarm device, which issues an alarm signal when the filter element differential pressure exceeds the set value.
Low Oil Pressure Protection Device When the lubricating oil pressure is lower than the set value (generally 0.1-0.15MPa), an alarm signal is issued first. If the pressure continues to drop to 0.05-0.08MPa, the engine is automatically shut down for protection.
Automatic Circulation System Equipped with an automatic lubricating oil circulation system with settable cycle time. Both the cycle time relay and the circulation time relay are adjustable to ensure that the lubricating oil is evenly distributed at each lubrication point during the unit’s standby period.
Heating Device Equipped with a lubricating oil heating device. The heating power is determined according to the tank volume to ensure that when the ambient temperature is lower than 5°C, the lubricating oil temperature can rise to above 20°C, ensuring good fluidity of the lubricating oil when the engine starts.
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3. Control Cabinet Technical Parameters

3.1 Control Logic and Functional Requirements

As the core of generator set control, the control cabinet must have functions such as distributed control, parallel synchronization, and load distribution to ensure the safe and stable operation of the unit. Specific requirements are as follows:

Control Function

Technical Requirements

Control Method Adopt distributed logic control method. Each unit has independent control and operation capabilities to avoid the paralysis of the entire system due to the failure of a single control point.
Parallel Synchronization The unit control cabinet is equipped with a parallel synchronizer. The synchronization accuracy is ≤±0.5°, and the synchronization response time is ≤1 second to ensure smooth parallel operation of multiple units.
Load Distribution Equipped with a fail-safe adaptive load distribution/droop operation method. When the communication link of the parallel system is lost, it can still ensure uniform load sharing, with load distribution unevenness ≤±10%, achieving seamless transition to the fail-safe mode.
Manual Parallel If there is a problem with system control, each unit can be manually paralleled with the busbar separately. During manual paralleling, phase, voltage, and frequency synchronization indicators should be available to ensure safe parallel operation.
Automatic Unit Addition/Reduction It has the function of automatic unit addition/reduction. The number of parallel units is automatically adjusted according to the actual load situation (increase units when the load rate exceeds 80%, and reduce units when it is lower than 40%). The process of unit addition/reduction should be stable without obvious voltage and frequency fluctuations.
Manual Setting of Parallel Unit Quantity The main control cabinet has the function of manually setting the number of units that send power after the diesel engine is successfully started, which is convenient for flexibly adjusting the number of parallel units when the load of the data center is not full in the early stage, reducing energy consumption.
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3.2 Alarm and Status Display Functions

The main control cabinet must have comprehensive alarm and status display functions to provide real-time feedback on the system’s operating status, facilitating monitoring and troubleshooting by operators. Specific requirements are as follows:

Display Category

Specific Content

Technical Requirements

Status Display Remote system start, system test, load
demand control mode, load online, generator set operation, generator set alarm, bus overload, load cut-off/unload, fuel tank oil level status, oil pump working status, system control failure
Use solid-state alarm and
status indicators, with clear indication and uniform brightness, visible clearly even in the machine room’s strong light environment; status information should be displayed locally at the same time and uploaded to the BMS system and power monitoring system through a unified interface
Parameter Display Unit parameters (voltage, current, power, frequency, power factor), load control display (load increase/decrease status), load demand display (number of online generator sets required), bus AC parameter summary (bus voltage, current, power, frequency), information/clock setting Display through a high-resolution programmable graphic interface panel, with a Chinese interface and hierarchical menu design for easy operation; parameter display accuracy: voltage ±0.5%, current ±0.5%, power ±1%, frequency ±0.02Hz
Alarm Function Equipped with an alarm horn and mute button, alarm sound intensity
≥85dB (at 1m distance); alarm types include unit fault alarms (low oil pressure, high water temperature, overspeed, etc.), system fault alarms (communication failure, control failure, etc.), bus fault alarms (overload, overvoltage, undervoltage, etc.)
Alarm signals need to have priority classification, with urgent alarms
(such as unit overspeed, bus short circuit) prompted first; alarm information needs to record occurrence time, fault type, fault parameters, storage capacity ≥1000 items, and no loss when power is off
Password Protection Equipped with password protection function, divided into operator authority and administrator authority. Operators can only perform daily monitoring and simple operations, while administrators can perform parameter setting, fault reset and other advanced operations to prevent unauthorized operations
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3.3 Control Functions and Data Monitoring

The main control cabinet must provide comprehensive unit control functions and data monitoring capabilities to ensure that the unit’s operating status is controllable and measurable. Specific requirements are as follows:

Function Category

Specific Function

Technical Requirements

Unit Control Manual start/stop of generator set, fault alarm reset of generator set, manual parallel switch control Control operation response time ≤ 1 second, manual start/stop process is stable without inrush current; Fault reset can only be executed after fault elimination to prevent misoperation
Data Monitoring Generator set output line-line voltage, generator set output current, generator set output power factor, generator set output frequency, generator set active load, generator set output electric energy,
generator set control switch position, generator set start times, current generator set alarm and shutdown fault information
Data sampling frequency ≥ 1 time/second, measurement accuracy:
voltage ±0.2%, current ±0.2%, power factor ±0.005, frequency ±0.01Hz, electric energy ±0.5%; Fault information shall include fault code, fault description and occurrence time
System Control System test ON/OFF, load demand ON/OFF, load demand shutdown sequence, system control mode (automatic/manual) The system test mode can simulate working conditions such as main power failure and load change, and the test process does not affect the actual load power supply; The load demand control mode can reduce fuel consumption and light load wear of the unit, and improve the service life of the unit
Alarm Summary Record all alarms and specific state changes of the system, display
the latest alarm or state information, including occurrence times, name, time, clear time, actual data, unit limit, high/low display
Historical alarm records can be browsed through “page up” and “page
down” buttons, and alarm records can be exported to U disk or uploaded to the monitoring system through communication interface, which is convenient for fault analysis and traceability
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3.4 Load Control and Interlocking Functions

The main control cabinet must have flexible load control and reliable interlocking functions to ensure safe system operation. Specific requirements are as follows:

Function Category

Specific Function

Technical Requirements

Load Control Manual load increase/decrease operation, low frequency/over frequency protection reset, adjustment of unloading delay setting (adjustable from 0-60 seconds), manual loading button, unloading recovery, manual unloading The rate of manual load increase/decrease is adjustable to avoid large fluctuations in voltage and frequency caused by sudden load increase or decrease; The unloading delay setting can be adjusted according to load characteristics to prevent mis-unloading caused by instantaneous load fluctuations
Interlock Function “First unit start valid” detection control, providing interlock and control signals for the parallel switch of each unit to avoid two units accidentally paralleling into the uncharged bus at the same time Interlock signals adopt hard-wired mode, response time ≤ 0.1 second, ensuring reliable interlock action; Only after the first unit is successfully paralleled into the bus, other units can perform parallel operation
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3.5 Network Communication Function

The main control cabinet must provide a standard communication interface to achieve seamless integration with the monitoring system. Specific requirements are as follows:

Communication Parameter

Technical Requirement

Interface Type Provide at least 1 BMS interface and 1 power monitoring interface, using standard RS485 interface
Communication Protocol Support standard open protocols (such as Modbus-RTU protocol) to ensure compatibility with monitoring systems of different brands
Data Transmission Diesel generator and all corresponding monitoring data (operation parameters, status information, alarm information) can communicate with the main unit of the data center weak current monitoring system through a unified interface, with a data transmission rate ≥9600bps and a transmission bit error rate ≤10^-6
Monitoring Function The main unit of the data center weak current monitoring system can monitor and control all operating states of the diesel generator system that need to be monitored. All display pages are designed with a system alarm function. No matter what parameters the system is monitoring, if an alarm or shutdown fault occurs, the system will immediately prompt an alarm
Communication Distance The maximum communication distance of the RS485 interface is ≥1200 meters. If the distance is exceeded, repeaters need to be equipped, and the number of repeaters can be increased according to actual needs
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3.6 AC Electrical Parameter Monitoring

The main control cabinet needs to comprehensively monitor the system’s AC electrical parameters to provide data support for system operation status assessment and fault diagnosis. Specific monitoring parameters are as follows:

Monitoring Parameter

Technical Requirement

Current Parameter Phase current of each phase, total current, measurement range 0-120% rated current, accuracy ±0.2%
Voltage Parameter Line voltage and phase voltage of each phase, measurement range 0-120% rated voltage, accuracy ±0.2%
Power Parameter Active power, apparent power, reactive power, active power accuracy ±1%, apparent power accuracy ±1.5%, reactive power accuracy ±2%
Power Factor Measurement range 0.2 (lagging) -1-0.2 (leading), accuracy ±0.005
Frequency Measurement range 45-55Hz, accuracy ±0.01Hz
Electric Energy Active electric energy (kWh), reactive electric energy (kVArh), accuracy ±0.5% (active), ±1% (reactive)
Load Demand Power Calculate the required load power of the system in real time, accuracy ±2%, providing a basis for automatic unit adding and reducing
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