1. General

1.1 Section includes

  1.1.1 The Contractor shall supply the medium voltage switchgear as specified herein. 1.1.2 Switchgear application describes air-insulated metal-enclosed medium voltage switchgear. 1.1.3 Medium voltage switchgear is designed to equip high power indoor {Option:} [HV/MV], [MV/MV] switchboards.  

1.2 Standards

Medium voltage switchgear shall be designed, manufactured, assembled and tested in accordance with the following standards:

• IEC 62271-1 Common specifications for high-voltage switchgear
• IEC 62271-200 AC metal-enclosed switchgear and controlgear for rated voltages above 1 kV and up to and including 52 kV
• IEC 62271-100 High-voltage alternating-current circuit-breakers
• IEC 62271-102 High-voltage alternating current disconnectors and earthing switches
• IEC 62271-106 High-voltage alternating current contactors
• IEC 62271-103 Switches for rated voltages above 1 kV up to and including 52 kV
• IEC 60282-1 High-voltage fuses - Part 1 : current-limiting fuses
• IEC 60255 serie  Measuring relays and protection equipment
• IEC 61869-1 Instrument transformers - Part 1 : general requirements
• IEC 61869-2 Instrument transformers - Part 2 : additional requirements for curent transformers
• IEC 60044-8 Instrument transformers - Part 8 : electronic current transformers
• IEC 61869-3 Instrument transformers - Part 3 : additional requirements for inductive voltage Transformers

1.3 Quality Assurance

  1.3.1 Manufacturer: Company specializing in medium voltage metal-enclosed switchgear with at least 30 years documented experience. The manufacturer of the switchgear must be the same as the manufacturer of the circuit breaker and contactor devices. 1.3.2 Conformity assessment: Manufacturers of MV switchgear shall be able to manage a first party conformity assessment procedure, as defined by ISO 17000, and provide the associated deliverables “Declaration of Conformity” for the performances stated in this specification. The supplier shall ensure the validity of the declarations over the time.  

2. Equipment

2.1 Medium Voltage Switchgear Assembly

2.1.1 The switchboards shall be modular and extensible at site. They shall comprise functional units as defined by IEC 62271-200. The factory-made functional units shall be bolted together at the place of use. 2.1.2 Switchboard dimensions: 2.1.2.1 {Option :} [the width of standard switchgear up to 12kV/40kA/1250A shall be equal to 650mm] [For all other standard switchgear, the panel width shall be no wider than 1000mm] 2.1.2.2 All standard functional units of the switchboard shall have the same height and depth, which shall be no more than 2330mm and 1605mm. 2.1.2.3 The switchboards shall be built so as to require no access to the rear section, for installation or operation, in order to be installed at a distance of 100mm or less from the wall behind them.
It can also have the possibility to have a rear access and an installation in the middle of a room. 2.1.3 The functional unit outer enclosure shall have a degree of protection of IP3X {option:}[IP4X].
The partitions between compartments of the same cubicle shall have IP2XC. 2.1.4 The cubicle shall be of LSC 2B (Loss of Service Continuity) and PM (Partition Class) classes as defined by IEC standard 62271-200. And it shall comprise three high voltage compartments and one LV cabinet:
- Busbar compartment, tool accessible
- Circuit breaker compartment, interlock accessible
- Cable compartment, interlock accessible
- Low voltage cabinet 2.1.5 Cable and bar connections: Power connection in standard for “incomer” and “feeder” cubicles shall be {option:} [bottom-entry cable connection] [top-entry cable connection] [top-entry bars connection]. 2.1.6 {option:}  Internal Arc Class (IAC) 2.1.6.1 The cubicles shall be internal arc classified by IEC 62271-200 of {option:}[25kA 1s] [31.5kA 1s] [40kA 1s] [50kA 1s], {option:}[AFLR] [AFL]. 2.1.7 {Option:}Thermal monitoring device
There shall be permanent monitoring of the temperature rise of the power circuits, in order to avoid the temperature reaching the stage where equipment is damaged. The thermal monitoring shall use sensors using energy harvesting and wireless communication avoiding any wire surrounding MV active parts. 2.1.8 The plates used as the visible parts of the switchboard shall be painted. All non-painted steel parts shall be zinc-plated or galvanized. 2.1.9 The switchboard shall meet specific application {option:}[Seismic areas] [marine] [nuclear] (if any of these applications is required, further information about related performances or characteristics shall be supplied)  

2.2 Ratings

  2.2.2 The cubicles shall not require forced ventilation when the rated current is equal to or less than 3150A and service condition are normal  

2.3 Switching Devices

2.3.1 It is mandatory for the switching devices that equip the functional units to be made by the switchboard supplier, or by a manufacturing plant that belongs to the same company. 2.3.2 Functional units shall be available with following withdrawable devices: - Withdrawable circuit breaker,
- Withdrawable contactor with fuses,
- Switch disconnector,
- Withdrawable earth connecting truck,
- Withdrawable disconnector truck, 2.3.2.1 The shutters for withdrawable parts shall be able to be locked out individually by a padlock. 2.3.2.2 Racking in and racking out operations shall be carried out only with the door closed and, for a circuit breaker or a contactor, when the circuit breaker or contactor operating auxiliaries are connected. It shall only be possible to open the door when the withdrawable part is in the “racked out” position. 2.3.3 Circuit breaker: 2.3.3.1 The breaking medium of circuit breaker, contactor shall be vacuum. The breaking medium of switch (switch-fuse combination function) shall be in Air. 2.3.3.2 The circuit breaker shall be designed so as to have class E2 (circuit breaker with extended electrical endurance) of electrical endurance, and class M2 (circuit breaker with extended mechanical endurance, mechanically type tested for 10 000 cycles) of mechanical endurance, as defined by IEC 62271-100. 2.3.3.3 The circuit breaker shall be in accordance with ANSI C37.013 for Generator incomer   2.3.4 Cable earthing switch: 2.3.4.1 The earthing switch shall have full making capacity in accordance with IEC standard 62271-102. 2.3.4.2 It shall be mechanically interlocked with the main switching device. Solutions involving key-locking, padlocking or electrical locking won’t be authorised to perform this function. 2.3.4.3 A {option:}[key-locking] system shall allow the earthing switch to be locked in the {option:}[open] [closed] position. 2.3.4.4 The operation devices of earthing switch, as well as {option:}[electromagnetic locking] [key-locking] [padlocking] devices and voltage present indicators, shall be grouped in dedicated area. 2.3.5 Operation of switching devices 2.3.5.1 Handles shall be used for all operations (racking in/racking out withdrawable devices, open/close earthing switch, racking in/racking out fuses of VTs (if applicable)). {option:} It shall be possible to have motorized earthing switch to close/open Earthing switch remotely. 2.3.5.2 If there is extraction tool, there shall be mechanical interlock for the withdrawable devices extraction operation, in order to make it impossible to extract a device unless the extraction tool is solidly locked to the functional unit, and impossible to unlock the extraction tool unless withdrawable device is locked to the tool or in the functional unit. 2.3.5.3 The various operations of circuit breaker and earthing switch must be done in front of the switchboard. When the racking operations are completed, they shall be confirmed by means of a dedicated indicator. 2.3.5.4 Operations of circuit breakers and earthing switches shall be described solely in the form of explicit symbols and colour codes. Instruction using texts will not be accepted. There shall be indicators to show the positions of switching devices, of withdrawable parts and of earthing switches.  

2.4 Current and Voltage Sensors

2.4.1 Current sensors: 2.4.1.1 Phase-phase sensors conventional current transformer {option:} [with primary winding] [without primary winding] 2.4.2 Voltage sensors: 2.4.2.1 The voltage sensors shall be installed at the bottom of functional units, in front of the cables. 2.4.2.2 The voltage sensors shall be {option:}[phase-earth] [phase-phase] type, {option:}[with fuse] [without fuse].
The fuses (if applicable) shall be fixed or withdrawable type  

2.5 Power Busbars and Earthing Circuit

2.5.1 Power busbars: 2.5.1.1 A copper busbar of flat formation type shall ensure the flow of power within the switchboard. The busbars shall be flat, parallel, and identical within each functional unit. 2.5.1.2 {Option:}[ the busbars should be silvered to prevent a risk of corrosion.] 2.5.2 Earthing circuit: 2.5.2.1 Copper earth conductors 2.5.2.2 The earth conductors of all cubicles shall be connected to one another as well as connected to the main earth conductor. The main earth conductor shall be installed in the cable compartment.

Protective relay: Requirements for the manufacturer

  The manufacturer shall have the Environment Certification ISO 14001. The manufacturer/supplier shall have a permanent representative office with a trained and skilled support staff, in the country or in the region where the Digital Relays are delivered, in order to prove his commitment for local or regional support and to provide a channel for communication.
The manufacturer shall be able to offer commissioning of the Digital relay to be carried out by the local or regional office. The Digital Protective Relay shall comply with the most relevant national, international standards and recommendations for industrial electrical distribution (IEC, EN, UL, CSA) The relay manufacturer must ensure that the source of raw materials come from reliable source in terms of sustainable environment development. The manufacturer shall posses RoHS certificate which refers to EU directive: RoHS Directive 2011/65/EU and be able to supply the Product Environmental Profile (P.E.P) of the device on the engineer’s request.

Protective relay: Requirement for the product

General features

  The Protection and Control device shall be of numerical type and designed to meet a high degree of dependability, security and maintainability.
{Option Sepam80} [To increase the level of protection safety without lowering the process availability the relay shall have a Safety Integrity Level equal to IEC 61508 -SIL2.] The relay shall be disconnectable type, for replacement in maximum 10 minutes.
{Option Sepam60-80} [Relay shall have removable memory block, storing all settings, programs, data; this memory block will then be reinstalled “plug and play” on the new relay.] One unique relay’s engineering software (based on standard Windows operating systems) shall provide all necessary tools and functions to configure and operate the devices.
The programming and configuration shall be carried out locally (front access) through a USB port and remotely through a communication network, mainly an Engineering LAN (E-LAN) with adequate passwords to prevent any illegal intrusion.
Programming and configuration shall also be able to be prepared on a PC file directly (unconnected mode) and down-loaded locally or remotely into the relay according to relevant protocol used. The relay shall embed a local Human Machine Interface (HMI), tailored to most languages. Relay shall accommodate low power current transformer (IEC 60044-8) to combine measure and protection in the same sensor; and maintain linear response under high currents.
Provisions shall be made in the switch gear cubicle for testing and calibrating the relay by current injection using an external source, without disconnecting the permanent wiring. The relay should not contain calibration files or similar, the calibration should be automatic. The Protective Relay shall offer the following connection capabilities; some could be in option adding cards: {CHOICE Sepam40}

{CHOICE Sepam60}

{CHOICE Sepam80}

Control functions

  The relay shall contain predefined control functions, in particular:
- Directly control the circuit-breaker or other device
- Logic discrimination as an option (ANSI 68)
{Option Sepam60-80}
[- Automatic transfer with synchro-check
- Load shedding followed by automatic restarting of motors The relay HMI shall also allow configuration of specific interlocking conditions.
It must be possible to configure specific interlocking conditions inside the relay for increased safety of the operator.]

Measurement functions

According to the usage, the Relay must offer following measurement and shall display the data on the HMI:
- Current: RMS/ Demand/ Peak
- Current residual: calculated/ measured
- Voltage phase-phase, phase-neutral
- Voltage residual: calculated/ measured
- Power: Active/ Reactive/ Apparent/ Peak demand/ Power factor
- Active and reactive energy: calculated/ by pulse counting
- Temperature
- Motor or Generator Rotation Speed

 {Option Sepam 60-80}Logs, records for Network and Motor diagnosis

  The relay shall provide a sequence of event record, disturbance record, for post-fault analysis. For increased diagnosis of the system, the relay shall have Datalog function: capability to record analog values (V, kW, Cos phi, motor speed, etc) per period of 1s to 24 hour. For increased diagnosis of motors, the relay shall record data during motor start, create trend graphs, in order to analyze motor condition, and associated loads.
Report shall be in the display (HMI), and also remotely accessible, in Comtrade format. For the information of the operator, the fault current value and the indication of the protection which has operated must be automatically displayed after a trip.]

Switchgear Monitoring and maintenance functions

  The Protective Relay shall continuously monitor the tripping circuit of the circuit breaker and record parameters useful for the maintenance of the circuit breaker, such as the cumulated squared Amperes and the operating time, charging time, number of operation.
Relay shall also monitor CT/VT supervision (ANSI 60/60FL) and Trip circuit supervision (ANSI 74).

Communication

  The relay shall support legacy serial protocols like IEC-870-5-103, Modbus RTU, DNP3.0 and Ethernet communication like IEC 61850 Ed1 and Ed2, Modbus TCP.
The relay must have other auxiliary protocols like: HTTP for Web Page access, FTP for file transfer, SNTP for Time Synchronization.

The relay shall offer redundant Ethernet communication, based on RSTP (rapid spanning tree protocol), in order to achieve fault tolerant architecture; maximum interruption time shall be 20ms. {Option Sepam60-80} [Modbus TCP and IEC61850 (Ed 2), including Goose message, shall be available simultaneously on the same Ethernet network.]

Protection functions

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