Q2118121 01 El CRT 00001
Q2118121 01 El CRT 00001
Q2118121 01 El CRT 00001
Project Name:
Filtration & Stockage Boues DAOUI KHOURIBGA”
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Filtration & Stockage boues DAOUI Q2118121 Electrical Design Criteria
Rev Description Originator Reviewer JESA Approver Revision Date Customer Approver Approval Date
A IFR O.TAFINE K.KHALLADI MA AZZAOUI 2/21/2022
Electrical Design Criteria Filtration & Stockage boues DAOUI KHOURIBGA (1)
Rev 0 01 December 2019 ii
Table of Contents
1. INTRODUCTION .............................................................................................................................. 5
2. Definitions ..................................................................................................................................... 6
1.1 POWER DISTRIBUTION SYSTEM ..................................................................................................... 7
2.1.1 Classification of Loads ............................................................................................... 7
2.1.2 Voltage levels ............................................................................................................ 7
2.1.3 Motor Voltage Selection............................................................................................ 8
2.1.4 Transformer Ratings .................................................................................................. 8
2.1.5 General ...................................................................................................................... 8
1.2 CONTROL SUPPLY FOR ELECTRICAL SYSTEM.................................................................................. 9
2.2.1 High voltage circuit breaker (Not applicable)............................................................ 9
2.2.2 Medium voltage circuit breaker ................................................................................ 9
2.2.3 Low voltage ............................................................................................................... 9
3. GENERAL EQUIPMENT DESIGN CRITERIA ....................................................................................... 11
3.1 Environmental ..............................................................................................................................11
3.2 Appearance ..................................................................................................................................11
3.3 Protection against Explosion and Fire Hazards ............................................................................11
3.4 Emergency System Design ...........................................................................................................13
3.5 Vital Systems Design ....................................................................................................................13
3.6 Degrees of Protection ..................................................................................................................13
3.7 Earthing System Design................................................................................................................14
3.7.1 Plant Earthing System (OnShore) ............................................................................14
3.7.2 Equipment Earthing System ....................................................................................14
3.7.3 Main Substation ......................................................................................................14
3.7.4 Earthing and Bonding Equipment ...........................................................................15
3.7.5 Instrumentation and Communications Earthing .....................................................15
3.7.6 Transfer Potentials ..................................................................................................15
3.7.7 Site Boundary ..........................................................................................................15
3.8 Lightning Protection.....................................................................................................................15
3.9 Minor Systems .............................................................................................................................15
3.9.1 Lighting Design ........................................................................................................15
3.9.2 Communications......................................................................................................16
3.9.3 Fire Alarm System....................................................................................................16
3.9.4 Motor Controls ........................................................................................................17
3.9.5 Power System Protection ........................................................................................17
3.10 Electrical Equipment Selection ....................................................................................................18
3.10.1 Emergency Diesel Generation .................................................................................18
3.10.2 Power Factor Correction .........................................................................................18
3.10.3 HV Equipment (Not applicable) ...............................................................................18
3.10.4 Grid Connection.......................................................................................................19
3.10.5 Primary MV switchboards .......................................................................................19
3.10.6 Main Power & Motor control centers .....................................................................20
3.10.7 HV/MV Transformers (Not applicable)....................................................................20
3.10.8 MV/LV & LV/LV Transformers .................................................................................20
3.10.9 Motors .....................................................................................................................21
This document presents the Electrical Design Criteria and defines the standards and procedures to be used
during electrical engineering and design activities for the “Filtration & Stockage Boues DAOUI KHOURIBGA.”
The Electrical Design Criteria ensures uniformity and consistency of the design by describing:
While this document provides general guidance, it shall not be a substitute for good engineering judgment
which should be applied as appropriate with the approval of the respective Lead Electrical Engineer.
The Electrical Design Criteria supports the Basis of Design. The Basis of Design provides the electrical system
performance necessary to meet the process plant requirements.
The Customer shall formally approve this document before the design is commenced.
All voltages less than 1000 volts listed in this document are utilization voltages, nominal voltage is the
transformer output secondary voltage.
CT Current Transformer
EN European Norm
HV High Voltage
IECEx IEC System for Certification to Standards relating to Equipment for use in Explosive Atmospheres
LV Low Voltage
MV Medium Voltage
VT Voltage Transformer
Vital service - A service which, when failing in operation or when failing if called upon, can cause an unsafe
condition of the process and/or electrical installation, jeopardize “life-safety” systems, or cause major
damage to the installation. Some of these loads are designated as “emergency” loads by some national
codes.
Essential service - A service, which, when failing in operation or when failing if called upon, will affect the
continuity, the quality or the quantity of product produced. (Caution: This term is defined in different
ways in different national or facility specific codes.)
Voltage Levels
Equipment Nominal No. No. Frequency Fault Remarks
Voltage of of Level
Phas Wires
es
LV System-4 220V 1Ph+ 2 50 HZ TBD Scheme TBD (Motor heaters and auxiliaries)
N wires
For isolated motors of a given size range or for certain motors furnished with specialty equipment, the
above voltage-motor size assignment may vary.
10 kV TBD
2.1.5 General
VOLTAGE DROP
3.1 Environmental
Electrical equipment, installation materials, wiring and cabling, etc. will be suitable for the overall climatic
conditions, their position within the installation and the local environment. The conditions are likely to
encompass exposure to a moisture and salt laden atmosphere, sea spray, sunlight, extremes of temperature
and humidity, fungal growth, abnormal vibration, and shock.
The insulating and dielectric materials used in all electrical equipment shall be non-toxic and shall not contain
compounds that are persistent and/or hazardous environmental contaminants, e.g. polychlorinated
biphenyls (PCBs). JESA has a global prohibition on the use of asbestos.
The equipment specifications and datasheets will detail the environmental conditions.
3.2 Appearance
Electrical equipment will be painted as far as possible following the general colour scheme of the plant. The
electrical equipment should be a consistent defined colour so that people working in the plant recognize the
electrical equipment items as being electrical because of the colour.
The area classification drawings, used in conjunction with the national or regional electrical installation code,
will be the basis for selecting electrical equipment for various locations. The specification and selection,
installation and maintenance of certified equipment for hazardous locations shall be in accordance with the
applicable national and international standards.
Ex d Flame-proof enclosure.
Ex e Increased safety.
Ex i Intrinsical safety.
Ex p Pressurized enclosure.
Ex n type of protection n, use in zone 2.
All equipment specifications will request certificates of compliance issued by a recognized testing
organization.
The change-over to the emergency power supply shall be automated. If necessary, sequenced starting of the
electrical equipment served by the emergency power supply shall be provided.
Voltages Load
Motors IP55
Cabinets, junction boxes, control panels and all other outside enclosures IP65
Cabinets, junction boxes, control panels and all other enclosures installed indoor in pressurized IP41
and air-conditioned rooms
The various earthing loops of the same voltage are intermeshed as far as possible in order to achieve a low
earthing resistance. If necessary, the earthing resistance can be further improved by installing additional
earthing rods.
The plant earthing system resistance to each earth electrode shall not exceed < 5 ohms “reference as NFPA
& l'IEEE” (add special requirement for HV substations 1 Ohm).
Below grade earthing conductors shall be buried a minimum of 600 mm and shall be installed with slack
between connections. Underground connections shall be exothermic weld type.
Unless otherwise specified, other electrical equipment operating below 525V shall be earthed to the MCC
earth bus via an earthing conductor in the power supply.
Metal floodlight and street light poles, building frames, pipe racks, and large skids with several electrical users
shall be wire connected to the main earthing loop. The switches and fence shall be bonded to the main
earthing loop.
Single or parallel metallic tray runs along a pipe rack shall be earthed at regular intervals. Trays leaving a pipe
rack, tray expansion fittings, and hinge splice plates shall have bonding jumpers installed to ensure raceway
continuity.
An insulated earth bus shall be installed in the control room for instrument earths. This bus shall be isolated
from power earthing conductors and building structures. It shall be connected to a cluster of earth rods near
the building and from there shall be tied at one point to the main earth loop.
For equipment installed in existing plant, connections shall be made to existing earthing systems following
the same rules.
For equipment installed in existing substations, connections shall be made to existing earthing systems
following the same rules.
Metal sheaths and armoring of cables shall be earthed in the switchgear and at the load end. Care has to be
taken to ensure that the metal sheaths and armoring are interconnected at cable branches or joints.
To bridge the insulating effect of the anti-vibration mountings on mechanical packages, bonding conductors
will be used to connect the insulated equipment to the adjacent structural steel.
Air terminals are to be installed on, or adjacent to, buildings and structures susceptible to lightning strokes.
Elevated buildings must be equipped with external lightning protection consisting of arresters and
conductors which are connected with the earthing system via aboveground isolating terminals.
All major steel structures, platforms, equipment, machinery and other non-conducting metallic components
of electrical equipment and instrumentation in buildings and plant sections are to be connected to the
earthing system via earthing and bonding.
No separate earth connections are required for equipment, items, vessels and machinery which are directly
attached to steel structures.
- Normal lighting is supplied from the main distribution system and will constitute 70 to 90% of the
illumination installed.
- Emergency service lighting will be approximately 10 to 30% of the general installation connected to
the emergency distribution system.
Escape lighting will be provided in muster areas and escape routes by battery back-up emergency fittings,
with supply from the emergency distribution system.
The (in-service) lighting intensities measured 1 m above floor shall be provided as per EN/ISO standards.
Power shall be supplied to the lighting circuits from lighting distribution boards installed within the
substation/plant.
Outdoor active 50
Street lighting 20
Workshops 150
Halls:
- Storage area 20
- Stairways and walkways 60
3.9.2 Communications
I&C/VDS design criteria shall be referred.
Unless otherwise specified, Local start/stop/emergency Stop stations with lock off emergency stops will be
provided for all drives.
The DCS will communicate with the individual starters via a hardwired and communications interface, as
required in the project specifications.
ON/OFF.
STOP.
Running.
Fault.
Local/remote.
For other options, the specifications and datasheets of MV/LV switchgears shall be referred.
Microprocessor controlled motor starters will be used. These systems shall provide drive monitoring and
protection features including self-diagnostics and communication facilities.
For Motors equipped with VFD, a speed indication and raise/low or potentiometer shall be included in the
local control station.
The emergency stop shall be able to be locked and tagged in the off position. The control stations shall be
equipped with ammeters for motors of 22 kW and above.
Unless otherwise specified, the local control switches are directly wired to the motor feeder in
switchgear/MCC.
Motor-operated actuators shall be equipped with an integrated power and control circuit, including limit
switches and torque shut-down functions, etc.
All protective devices, including relays and current transformers (CT’s), are to be adequately rated to
withstand the prospective short circuit current which can flow or be induced.
Multifunction protective relays will be used as required in the single line diagrams, schematics, and
switchgear specifications.
Back up protection will be provided by time and time-current grading of upstream protection devices,
supplemented by automatic communications schemes where appropriate.
Current transformers (CTs) and voltage transformers (VTs) shall be specified with characteristics, e.g. rated
output and accuracy class, which are adequate for the associated protection, control and/or monitoring
equipment.
Unless otherwise specified, separate CTs should be used for metering and protection services.
The rated output of VTs shall, as a minimum, be equal to the connected burden of the protection, control
and/or monitoring devices, including the load burden, plus 20% spare, rounded up to the next standard
rating.
Diesel engine.
Generator.
Air intake and exhaust air system.
Starting system (battery or/and air starter).
Fuel system
Switching and control facilities.
The generator shall be of the three-phase synchronous type with brushless exciter, suitable for parallel
operation with the mains. The power rating shall be based on an inductive power factor of 0.8.
The automatic connection and disconnection depend on the reactive power. The controller measures the
reactive power and, whenever the pre-set cos phi threshold is exceeded, it issues delayed switching signals
for connecting and disconnecting the capacitors by means of an output relay.
In the case of switchgear with two incoming feeders and a bus-tie, preferably a compensation system may
be provided per bus-bar section.
The competed surge arrester shall be house in a porcelain insulator. The porcelain housing shall be
dimensioned to provide a leak free interface with the end caps. The housing shall withstand the lighting
impulse voltage of the arrester. The surge arrester shall be hermetically sealed to ensure no moisture
The operating mechanism shall be fixed at the base frame, in a weather proof, vermin proof and dust proof
housing. The degree of protection shall be class IP 55 as per IEC-144. The operating mechanism shall be
provided with a universal joint to allow for a reasonable degree of out of alignment of the operating rod.
The VT shall be an oil immersed type equipped with brown porcelain insulators. The VT must not be equipped
with arcing horns. The VT shall be hermetically sealed.
The circuit breakers shall be for outdoor installation, three-phase, motor-spring-operated, trip-free in any
position and SF6 gas type with porcelain supporting insulator. All the three poles of circuit breakers shall be
operated by local electrical and remote/electrical from the mechanism in the housing.
The circuit breakers shall be completed with operating mechanism, supporting structure, piping, conduits,
wiring and any other accessories needed for operation. The operating mechanism shall be suitable for
mounting on a circuit breaker supporting structure, and below the circuit breaker in a weather-proof, dust-
proof, venin-proof and well-ventilated housing. The degree of protection shall be class IP 55.
The power supply for the Filtration & Stockage Boues DAOUI KHOURIBGA will be from 10 kV substation
Adaptation DAOUI
Circuit breakers shall be vacuum type. Circuit breakers shall be equipped with spring energy store and spring-
winding motor sufficient for three switching operations (OFF - ON – OFF) and incorporate solid-state
protection relays and local electrical metering at each feeder, and at each incomer.
The protection relays will be self-monitoring, with trip circuit supervision capability, remote setting capability
and a full suite of monitoring parameters for both local and remote reading.
Compartments enclosing potential transformers, control transformers and other equipment essential to the
operation of the switchgear will be readily accessible and be clearly marked.
For temporary solution to supply existing consumers during plant shut-down, Fixed type switchboard shall
be used.
The power transfer between transformer and LV switchgear and MCC shall be by XLPE cables.
All components will be rated and able to withstand the full fault level specified for one second and will have
type test certificates indicating that they have been tested by a recognized independent test laboratory.
Each starter unit will have components designed for TYPE 2 Co-ordination according to IEC 60947-4-1.
The HV transformers shall be suitable for outdoor installation (despite being mounted under shelters) and
ONAN/ONAF cooling. HV transformers will be capable of operating continuously at rated power at the
maximum specified outdoor ambient temperature.
High voltage windings will be provided with tapings and a facility for on-load tap changing with a tapping
range of ± 15 % (in 1.5 % steps) unless system design dictates otherwise.
The transformers will be capable of operating continuously at rated power at the maximum specified outdoor
ambient temperature.
When specified in transformer datasheet, high voltage windings will be provided with tapings and a facility
for off-circuit tap changing. A manually operated means of changing the taps shall be provided, with a tapping
range of ± 5 % (in 2.5 % steps) unless system design dictates otherwise. For dry type transformers bolted
cable taps are acceptable.
3.10.9 Motors
Unless otherwise specified, the winding insulation shall be temperature class F, with a temperature rise to
class B at rated load.
The winding ends shall be wired to terminals in the junction box and, if necessary, in the neutral point
terminal box. A further terminal for connection of the earthing conductor shall be provided in the terminal
box. Two earth terminals shall be provided on opposite sides of the outside of the motor housing.
All motors are equipped with space heaters. The space heaters are fed from the LV-compartment of the HV-
switchgear and will be energized if the motor is not in operation.
The lubrication for anti-friction bearings shall be by means of grease via grease nipples or, in the case of
friction bearings, by circulating oil or slip rings. Type of lubricant, quantity and relubrication intervals shall be
specified in the documentation.
Vibration of motors shall be limited to values as specified in IEC 60034-14 according to grade A.
The motors shall be squirrel-cage induction motors for direct on line starting.
Unless otherwise specified, the power rating specified on the nameplate is the shaft power that the motor is
capable of delivering under the ambient conditions specified on the nameplate during continuous duty
(operation type S1).
In rating the motors and the mains it is assumed that the voltage at the motor terminals will drop to 80% of
the nominal voltage and that the motors will accelerate satisfactorily up to rated speed.
A terminal shall be provided in the terminal box for connection of the earthing conductor.
Operating load, with an allowance for charging efficiency, battery ageing, and temperature variations.
A duration determined by application.
The UPS shall be provided with a microprocessor-based unit showing status, measurements and messages.
3.10.11 AC UPS
The AC UPS systems will comprise dual 100% rated rectifiers/inverters and dual 50% rated batteries.
These cabinets shall be installed in low voltage switch rooms or separate rooms (for instrumentation).
Distribution boards shall be provided with fixed mounted incoming and outgoing feeders including 20 %
spare feeders.
The UPS shall be provided with a microprocessor-based unit showing status, measurements and messages.
3.10.11.1 Batteries
There are three alternative types of battery that are technically acceptable for UPS duty:
The negative pole shall not be earthed, an overall earth fault monitoring relay shall be provided.
3.10.12 Cables
Cables will be suitable for service in the environmental conditions described for the plant.
Unless otherwise specified, nominal power cable ratings will be based on:
Derating factors will be applied as necessary to take account of installation configuration and variation in
ambient temperature, in accordance with IEC standards.
Cables partially or totally within the buildings will in addition to the above requirements be low smoke
emission, zero halogen type (less than 0.05%).
To ensure the proper design, installation and maintenance of electrical equipment in areas where flammable
gas or vapors may be present, the appropriate documentation shall be prepared. Documentation shall be
prepared in accordance with the requirements of IEC 60079-14 and the Hazardous Electrical Installation
Design Guide.
All equipment specifications will request certificates of compliance issued by a recognized testing
organization.
When planning, designing, manufacturing and installing a package unit, the supplier will use his experience
and know-how gained over many years in the installation and operation of such units.
In order to ensure this procedure, it is also permitted to use components which do not fully conform to
Customer’s or JESA’s specifications. This also applies to materials, corrosion protection and paint coats.
In all cases, prior to manufacturing, vendor shall obtain the formal approval from OCP/JESA for any deviation
or alternative solution.
3.13.1 Layout
The basic method of construction shall be aboveground cable in trays for power, control, and instrument
circuits. Underground construction shall be used for certain offsite circuits (e.g., street lighting and circuits
to equipment or buildings remote from the main pipe rack). An aboveground cable system shall be used for
lighting and receptacle circuits, as well as for the extension of instrument circuits beyond area junction boxes.
Area or unit substations shall consist of stepdown power transformers, a bus duct, secondary switchgear,
and motor control equipment. Area substations shall be centrally located with respect to the loads supplied.
Switchgear and motor control equipment shall generally be installed indoors in mechanically ventilated
switch rooms located in non-hazardous areas. When practical, this equipment shall be purchased factory
installed in prefabricated switchgear buildings.
Switchgear and MCCs will generally be front connected with single row switchboards.
Each switchboard (each bus section for double-ended switchboards) and medium-voltage motor control
assembly should be designed for expansion in at least one direction.
Provision shall be made for an approximate 20% increase in the number of low voltage motor starters. This
shall be accomplished by providing 20% future space or spare equipped feeders as specified in single line
diagrams and switchgear specification.
Where cables enter the switch room (e.g. cable slots under switchgear) the cable entry shall be sealed flame
retardant. The filler to be used is polyurethane foam with a cover of flam-mastic or rock-wool panels with a
cover of flam-mastic.
The battery room shall be designed to contain the battery banks only. The size of the room should be
adequate to allow access to at least three sides of each battery bank for maintenance purposes.
All non-current-carrying metalwork in the room, e.g. cable tray, battery stands, etc. shall be bonded to earth.
All metalworks shall be protected against corrosion.
HV power factor compensation equipment may be located in dedicated separate rooms inside the
substations.
The room height shall be minimum 3 m (clear height from floor level and/or false floor level).