Siemens SIPROTEC 7VE85 Paralleling and Synchronising Device

Siemens SIPROTEC 7VE85 Paralleling and Synchronising Device Suppliers,Exporters in India

ARP IMPEX is a supplier and exporter of Siemens SIPROTEC 7VE85 Paralleling Devices in India. We handle requirements for power plants, captive power systems, utility substations, industrial generating stations, generator control panels and replacement of older synchronising equipment.

The Siemens SIPROTEC 7VE85 is used to connect a generator to the power grid or to connect two electricity-supply systems safely. Before the circuit breaker closes, the device checks whether the voltage, frequency and phase angle on both sides are within the permitted limits.

Closing a generator breaker at the wrong moment can place heavy electrical and mechanical stress on the generator, transformer, coupling and switchgear. The 7VE85 calculates the correct closing point and considers the circuit-breaker operating time so that the contacts close when both systems are properly aligned.

The device can work under synchronous and asynchronous operating conditions. It can perform automatic synchronisation, provide synchrocheck approval for manual closing and send balancing commands to adjust the generator voltage and speed.

Siemens supplies the 7VE85 with 1.5-channel and 2-channel synchronisation arrangements. The 2-channel version uses separate measuring paths and different algorithms to provide a higher level of redundancy for critical power-generation applications.

The modular SIPROTEC 5 hardware allows the device to handle several synchronising locations, binary inputs, outputs, voltage inputs and communication requirements within one system.

For Siemens SIPROTEC 7VE85 price and availability, send the complete Siemens order code, required configuration, quantity and destination country.

What the Siemens 7VE85 Does

A generator cannot be connected to an energised grid simply by issuing a circuit-breaker closing command.

Before connection, the following conditions must be checked:

• Generator voltage
• Grid or busbar voltage
• Voltage difference
• Generator frequency
• Grid frequency
• Frequency difference
• Phase-angle difference
• Direction of frequency slip
• Circuit-breaker closing time
• Transformer vector-group correction, where applicable

The Siemens 7VE85 continuously compares the electrical conditions on both sides of the open circuit breaker.

When the values enter the permitted synchronising window, the device calculates when the closing command must be issued. It sends the command early enough to compensate for the mechanical operating time of the breaker.

The aim is for the circuit-breaker contacts to close when the phase-angle difference is as close as possible to the required value.

Generator-to-Grid Synchronisation

One of the main applications of the Siemens SIPROTEC 7VE85 is synchronising a generating unit with the electricity network.

The generator may be driven by:

• Steam turbine
• Gas turbine
• Hydro turbine
• Diesel engine
• Gas engine
• Industrial process turbine
• Combined-cycle power-plant equipment

Before connection, the generator speed and excitation must be adjusted so that its frequency and voltage match the grid.

The 7VE85 can issue raise and lower control pulses to the turbine governor and voltage regulator. Once the synchronising conditions are satisfied, it releases or sends the circuit-breaker closing command.

This arrangement is commonly used in generator control panels, turbine-generator control systems and power-plant synchronising panels.

Synchronisation of Two Power Systems

The 7VE85 can also synchronise two energised power systems.

This may be required when closing:

• Bus-coupler circuit breakers
• Bus-section circuit breakers
• Grid interconnection breakers
• Utility incomer breakers
• Plant tie breakers
• Transfer breakers between two power sources
• Circuit breakers connecting separate network sections

The device checks the voltage, frequency and phase-angle relationship between the two systems before permitting the breaker to close.

This helps prevent an out-of-phase connection between two live busbars or supply networks.

Siemens 7VE85 Synchronisation Arrangements

1.5-Channel Synchronisation

The 1.5-channel arrangement provides automatic synchronisation together with an additional monitoring or synchrocheck path.

It is suitable for many generating units and power-system switching applications where the project requires dependable synchronisation with an independent checking function.

Depending on the selected configuration, the device can support up to four or eight synchronising locations.

2-Channel Synchronisation

The 2-channel arrangement is selected for applications requiring greater redundancy.

It uses duplicated hardware paths and separate measuring algorithms. Both channels evaluate the synchronising conditions independently before the circuit breaker is allowed to close.

This arrangement helps reduce the possibility of an incorrect closing command caused by a common measuring or calculation fault.

The 2-channel version is commonly considered for:

• Large generating units
• Critical utility power plants
• High-value turbine generators
• Generator transformers
• Important grid interconnections
• Applications with strict availability requirements
• Power plants requiring redundant synchronisation checks

The final channel arrangement must be selected from the plant safety philosophy, generator rating, utility requirements and project specification.

Multiple Synchronising Locations

A generating station may have more than one circuit breaker through which a generator or busbar can be connected.

The Siemens SIPROTEC 7VE85 can manage up to eight synchronising locations, depending on the ordered functional configuration.

These locations may include:

• Generator circuit breaker
• Generator-transformer high-voltage breaker
• Bus-coupler breaker
• Bus-section breaker
• Grid incomer
• Auxiliary supply incomer
• Plant tie breaker
• Alternative grid connection

The required voltage measuring points can be selected internally through the device logic and connected input structure.

This reduces the need for separate external synchronising relays, selector switches and voltage-switching arrangements for each circuit breaker.

Automatic Synchronisation

During automatic synchronisation, the device compares the generator and system values and sends control commands to bring them within the permitted limits.

Typical balancing commands include:

• Voltage raise
• Voltage lower
• Frequency raise
• Frequency lower
• Speed raise
• Speed lower

The control pulses can be sent to the generator excitation system and turbine governor.

The Siemens 7VE85 includes stabilisation functions for frequency-control pulses. This helps prevent unnecessary control movement when the frequency difference is already approaching the acceptable range.

The number of balancing commands and the control arrangement depend on the selected device configuration.

Synchrocheck for Manual Closing

The 7VE85 can provide a synchrocheck function for manual circuit-breaker closing.

In this mode, the operator or plant control system issues the closing request. The 7VE85 checks whether the electrical conditions are acceptable before releasing the command.

The breaker is blocked from closing when:

• Voltage difference is too high
• Frequency difference is outside the setting
• Phase-angle difference is excessive
• One of the required voltages is missing
• The selected synchronising point is incorrect
• A supervision or measuring condition is not satisfied

This function can be used for generator breakers, bus couplers, grid interconnections and other circuit breakers that must not close out of synchronism.

Technical Specifications

The Siemens SIPROTEC 7VE85 is a configurable device. The actual hardware and functions depend on the complete order code.

• Brand: Siemens
• Product family: SIPROTEC 5
• Model: 7VE85
• Product type: Paralleling and synchronising device
• Main application: Generator and power-system synchronisation
• Synchronisation arrangements: 1.5-channel or 2-channel
• Synchronising locations: Up to four or eight, depending on configuration
• Operating conditions: Synchronous and asynchronous systems
• Manual closing supervision: Synchrocheck function
• Generator control: Voltage and frequency balancing commands
• Transformer consideration: Vector-group compensation and tap-changer voltage adjustment options
• Engineering software: Siemens DIGSI 5
• Hardware design: Modular SIPROTEC 5 platform
• Inputs and outputs: Expandable binary and analogue I/O structure
• Voltage inputs: Selected according to measuring and synchronising-point requirements
• Power supply: Standard or redundant supply options
• Typical auxiliary supply ranges: Depend on the selected hardware version
• Display options: Small display, large display or device without local display
• Mounting: Flush or surface mounting, depending on housing
• Communication: Serial and Ethernet communication options
• IEC 61850: Reporting and GOOSE communication on applicable configurations
• Process bus: IEC 61850-9-2 support with the required module and configuration
• Time synchronisation: Ethernet and dedicated time-synchronisation options
• Operating temperature: Extended temperature range on applicable hardware
• Circuit-board protection: Conformal-coated electronics
• Cybersecurity: Role-based access and network-security functions, depending on configuration
• Optional redundancy: Redundant power supply and communication arrangements
• Fault recording: Integrated event and fault recording
• Standards: SIPROTEC 5 protection, control and communication standards

These are family-level specifications. The number of synchronising points, voltage inputs, binary inputs, outputs, communication ports and optional functions must be confirmed from the complete Siemens 7VE85 order code.

Main Synchronising Functions

Depending on the selected configuration, the Siemens 7VE85 provides:

• Automatic generator synchronisation
• Synchronisation of two electricity-supply systems
• Synchrocheck before manual closing
• Synchronous-system closing
• Asynchronous-system closing
• Voltage-difference monitoring
• Frequency-difference monitoring
• Phase-angle monitoring
• Circuit-breaker closing-time compensation
• Frequency-slip evaluation
• Generator voltage balancing
• Generator speed and frequency balancing
• Transformer vector-group compensation
• Automatic adjustment of synchronising voltage with tap changer
• Management of several synchronising points
• Dead-bus and live-bus condition supervision
• Circuit-breaker closing supervision
• Monitoring of measuring circuits
• Switching-sequence logic
• Event and disturbance recording

The final functions available in the device depend on the ordered Function Points and DIGSI 5 configuration.

Optional Protection and Monitoring Functions

The 7VE85 can also include protection and monitoring functions where the project requires more than synchronisation.

Available functions may include:

• Active-power protection
• Reactive-power protection
• Reverse-power or low-power supervision
• Undervoltage protection
• Overvoltage protection
• Rate-of-voltage-change protection
• Underfrequency protection
• Overfrequency protection
• Rate-of-change-of-frequency protection
• Vector-jump detection
• Phase overcurrent protection
• Ground overcurrent protection
• Switch-onto-fault protection
• High-current instantaneous protection
• Circuit-breaker failure protection
• Circuit-breaker restrike protection
• Voltage comparison
• Trip-circuit supervision
• Circuit-breaker wear monitoring
• Synchrophasor measurement
• Process-bus integration
• Arc-protection integration

The device should not automatically be treated as the main generator protection relay only because optional protection functions are available.

Generator differential protection, stator earth-fault protection, rotor earth-fault protection, loss-of-excitation protection and other dedicated generator functions may require a Siemens SIPROTEC 7UM85 or another suitable protection device.

Features

• Designed specifically for generator and power-system paralleling
• Suitable for generator-to-grid synchronisation
• Supports synchronisation between two electricity-supply systems
• Available with 1.5-channel and 2-channel arrangements
• Independent measuring algorithms improve closing security
• Duplicated hardware available for critical synchronising applications
• Handles synchronous and asynchronous operating conditions
• Compensates for circuit-breaker operating time
• Supports up to eight synchronising locations
• Reduces the need for external voltage-selection equipment
• Provides automatic voltage and frequency balancing commands
• Includes synchrocheck for manually initiated closing
• Can consider transformer vector-group displacement
• Tap-changer voltage-adjustment function available
• Expandable binary inputs and outputs
• Modular hardware can suit small and large generating stations
• Protection and control functions can be added when required
• Integrated switching logic reduces external auxiliary relays
• DIGSI 5 supports settings, logic and commissioning
• IEC 61850 communication available
• GOOSE messaging supports substation automation
• Serial and Ethernet protocol options are available
• Optional redundant power supply increases availability
• Conformal-coated electronics suit harsh environments
• Fault and event records support investigation after switching
• Suitable for new power plants, retrofits and relay replacement
• Can combine several synchronising duties in one device

Applications

Siemens SIPROTEC 7VE85 Paralleling Devices are used for:

• Thermal power plants
• Gas-turbine power plants
• Steam-turbine generating units
• Combined-cycle power plants
• Hydro power stations
• Diesel generator plants
• Gas-engine power plants
• Captive power plants
• Industrial cogeneration plants
• Utility generating stations
• Generator control panels
• Generator circuit-breaker panels
• Generator-transformer units
• Grid interconnection panels
• Bus-coupler panels
• Bus-section switching
• Industrial power-management systems
• Refinery captive power systems
• Petrochemical plants
• Steel plants
• Cement plants
• Mining power systems
• Pulp and paper plants
• Chemical plants
• Data-centre generation systems
• Marine and offshore power systems
• Utility substations
• High-voltage switching stations
• Power-plant modernisation projects
• Replacement of older synchronising relays
• Migration from multiple synchronising devices to one modular system

Use in Captive Power Plants

Many industrial plants operate their own generators while remaining connected to the utility grid.

The generator may run continuously in parallel with the grid or connect only during certain production conditions.

The Siemens 7VE85 can manage the synchronising process before the generator breaker closes. It checks the generator voltage, utility voltage, frequency and phase angle and sends the closing command at the calculated time.

The device can also issue control pulses to the governor and automatic voltage regulator when the generator values need correction.

Industries searching for a Siemens 7VE85 synchronising relay for captive power plants should provide the generator rating, voltage level, circuit-breaker details and existing synchronising scheme along with the Siemens order code.

Use in Generator Control Panels

The 7VE85 can form the main synchronising section of a generator control panel.

The panel may also include:

• Generator protection relay
• Automatic voltage regulator
• Turbine governor
• Generator circuit-breaker control
• Annunciation system
• Metering equipment
• PLC or distributed control system
• Manual synchronising controls
• Synchronising lamps or synchroscope
• Trip and lockout relays

The 7VE85 exchanges signals with these systems through binary contacts, serial communication or IEC 61850, depending on the panel design.

The synchronising logic should be engineered from the actual generator, transformer, busbar and breaker arrangement. A standard configuration should not be copied between different power plants without checking the plant data.

Siemens 7VE85 and 7UM85 Difference

The Siemens SIPROTEC 7VE85 and 7UM85 are both used around generators, but their main duties are different.

• Siemens SIPROTEC 7VE85: Paralleling and synchronising device
• Siemens SIPROTEC 7UM85: Generator and motor protection relay

The 7VE85 checks the conditions for connecting the generator to the grid and calculates the correct circuit-breaker closing time.

The 7UM85 protects the generator against internal faults, abnormal current, abnormal voltage, earth faults, loss of excitation, reverse power and other electrical conditions, depending on its configuration.

Large generator projects may use both devices in the same protection and control system.

Siemens 7VE85 and a Basic Synchrocheck Relay Difference

A basic synchrocheck relay normally checks whether voltage, frequency and phase-angle differences are within set limits before allowing a breaker to close.

The Siemens 7VE85 can perform a much wider role.

It can:

• Automatically adjust generator voltage and frequency
• Calculate the correct closing command for asynchronous systems
• Compensate for breaker closing time
• Manage several synchronising locations
• Provide redundant synchronising channels
• Integrate switching logic and control
• Communicate with the station automation system
• Include additional protection and monitoring functions

A basic synchrocheck relay may be sufficient for one simple bus-coupler application. The 7VE85 is more suitable for generator units, multiple circuit breakers and power plants with higher synchronising requirements.

Selecting the Correct Siemens SIPROTEC 7VE85

The Siemens 7VE85 is not selected only by the model name. It is built from a configurable order code covering hardware, inputs, outputs, synchronising functions and communication options.

For an accurate quotation, provide:

• Complete Siemens 7VE85 order code
• Existing relay label photograph
• Required quantity
• Destination country
• Generator rated power
• Generator rated voltage
• Grid or busbar voltage
• System frequency
• Number of generators
• Number of synchronising locations
• 1.5-channel or 2-channel requirement
• Generator-to-grid or system-to-system application
• Circuit-breaker operating time
• Voltage-transformer arrangement
• Transformer vector group
• Number of binary inputs and outputs
• Required display type
• Auxiliary supply voltage
• Communication protocol
• Fibre-optic or electrical communication requirement
• Redundant power-supply requirement
• Optional protection functions
• DIGSI 5 project or existing configuration file, where available

For direct replacement requirements, the complete order code and existing DIGSI configuration are especially important.

Two Siemens 7VE85 devices may look the same from the front but have different voltage inputs, I/O modules, communication cards and licensed functions.

Siemens 7VE85 Replacement and Retrofit Requirements

For replacement of an existing paralleling device, check:

• Existing manufacturer and model
• Siemens order code, where already installed
• Generator and grid voltage
• Number of synchronising circuit breakers
• Existing voltage-selection arrangement
• Breaker closing times
• Governor control interface
• Automatic voltage regulator interface
• Required manual synchrocheck
• Existing communication protocol
• Available panel space
• Existing wiring and terminal details
• Required protection functions
• Plant shutdown schedule

The 7VE85 can reduce external synchronising equipment in a retrofit, but changes to wiring, voltage selection, logic and panel cut-outs may still be required.

The replacement should be reviewed by the plant protection and control engineer before the final order is placed.

Siemens SIPROTEC 7VE85 Supplier and Exporter in India

ARP IMPEX supplies Siemens SIPROTEC 7VE85 Paralleling and Synchronising Devices for power utilities, power plants, EPC contractors, generator manufacturers, panel builders, system integrators, industrial plants and export buyers.

We handle enquiries for Siemens 7VE85 generator synchronising devices, 1.5-channel synchronisation, 2-channel redundant synchronisation, multi-point paralleling systems, generator-to-grid synchronisation and replacement of older power-plant synchronisers.

Buyers looking for Siemens SIPROTEC 7VE85 price in India, Siemens 7VE85 generator synchronising relay supplier, Siemens paralleling device exporter from India or Siemens 7VE85 replacement can send the complete device order code for review.

The Siemens 7VE85 price depends on the synchronising arrangement, number of synchronising points, device housing, voltage inputs, binary I/O, power supply, display, communication modules and optional functions.

Send the complete Siemens order code, required quantity and destination country for price, availability and export quotation.