SAES-P-100
Basic Power System Design Criteria
SAES-P-101
Regulated Vendors list for Electrical
Equipment
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Definitions
Approval: Written approval of the ESD (Electrical Systems Division) Coordinator.
Base Voltage: The bus voltage calculated by starting with the nominal voltage at
the swing bus and calculated for each bus based on the transformer turns ratios.
Nominal voltage : The value assigned to a system or circuit of a given voltage
class for the purpose of convenient designation. The actual voltage may vary
above or below this value.
Swing Bus: A slack bus (or swing bus), defined as a Vδ bus, is used to balance the
active power |P| and reactive power |Q| in a system while performing load flow
studies.
Bus Tie Breaker: A breaker used to connect the two busses of secondaryselective system.
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Definitions
Captive Transformer: A transformer whose output is dedicated to a single piece
of utilization equipment.
Control gear: Equipment manufactured to either 16-SAMSS-503 (Low Voltage
Control gear), 16-SAMSS-506 (High Voltage Control gear) or 16-SAMSS-507
(High Voltage Motor Controller - Outdoor).
Critical Loads: Are loads: Where a single contingency failure could cause a loss of power
Which cannot be shut-down for a minimum of five consecutive days annually critical care
areas in clinics and hospitals, major office buildings
High Voltage: Voltages 1000 V or greater
Low Voltage: Voltages less than 1000 V
Switchgear: Equipment manufactured to either 16-SAMSS-502 (Low Voltage
Switchgear) or 16-SAMSS-504 (High Voltage Switchgear).
Switch rack: Equipment manufactured per 16-SAMSS-512.
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General
Electrical power systems shall be designed and constructed in accordance with
the latest edition of NFPA 70 (National Electrical Code) and ANSI C2
(National Electrical Safety Code).
Low voltage AC distribution systems shall be protected by circuit breakers.
Fuses shall not be used.
Only secondary-selective switchgear (A switchgear assembly consisting of
two buses connected with a single bus tie breaker.) shall be used to feed
critical loads
Fire pump installations, communications systems and Existing equipment
containing PCB refer in other NEC codes
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Design Basis
➢
System Voltage and Frequency.
• The frequency: 60Hz. Primary distribution : 13.8 kV, 3-phase, 3-wire. Secondary
distribution shall be either 4160V or 480V
➢
Low Voltage Systems
• At branch circuit/distribution equipment connection points 95% to 105% of nominal
voltage. At light fixtures: 91.7% to 104.2% of nominal voltage. And at utilization
equipment other than lights: 90% to 104.2% of nominal voltage.
➢
High Voltage Systems
• At branch circuit/distribution equipment connection points 97.5% to 105% of nominal
voltage. At the utilization device: 90% to 104.2% of nominal voltage.
Voltage Drop: Motor Starting at every utilization device anywhere in the electrical system,
shall not drop below 85% of the nominal voltage.
Direct Current Systems Maximum total voltage drop for main, feeder, and branch circuits
shall not exceed 5%. The average voltage drop in branch circuits shall not exceed 2% with
a maximum of 4% at the most distant load.
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System Studies
➢
Power System design (Load-flow, Short-circuit, Motor-starting) ETAP Software.
Transient Stability (Gen>10MW), Harmonic Analysis(Power Electronics), Switching
Transient Analysis (Shunt Capacitor)
➢
Transformer Test/ New Transformer: (7.5% impedance tolerance for load flow and
short circuit calculation) Off-load tap settings shall be assumed to be at the mid-point (neutral
position). existing systems, actual transformer off-load tap settings shall be used
Motor Loads
Operating Loads
Short Circuits
Switchgear
UPS
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Electrical Area Classification Design
➢ NEC (Article 500-510), SAES-B-068
➢ Certification Agencies (UL, etc)
➢ Installation per NEC in Hazards Location (Classes, Division
and Zones)
➢ Environmental condition
➢ Power System Protection (SAES-P-114)
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SAES-P-101
Regulated Vendors list for Electrical Equipment
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Definitions
9COM Material #: Commodity Material number.
SAMSS: "Saudi Aramco Materials System Specification".
SAP: Saudi Aramco corporate computer system that includes the
approved manufacturers.
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General
➢
Procurement of a product made by a manufacturer not listed as an approved
manufacturer in Saudi Aramco SAP system is not allowed without approval.
Requests for approval of an alternate manufacturer must be supported by
documentation identifying how the alternate manufacturer would better serve
Saudi Aramco over the manufacturers.
➢
The manufacturer listings within Saudi Aramco SAP system interpreted in the
following manner:
Manufacturer listed without Limitation: All products from the
manufacturer in the given category (9COM and, if applicable, SAMSS) are
acceptable.
Manufacturer listed with a "Limitation": Only the product that meets the
"Limitation" is acceptable. If noted as being manufactured "Under License",
only products made under the terms of the license agreement are acceptable.
Manufacturer is listed with a specific "Location": Only products made
in the specific location(s) or area(s) are acceptable.
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Acceptable Manufacturers Listing
Refer to Saudi Aramco SAP system for approved manufacturers for the
following 9COM:
Example
Equipment Description: Transformers, Power, Oil-Filled
9COM Material #: 6000000764
Specification: 14-SAMSS-531
➢
Class 14 (Transformers, Cable Tray)
➢
Class 15 (Power Cables)
➢
Class 16 (Control gear, Switchgear, Circuit Breaker, Transfer Switch, Cable
bus, Relay)
➢
Class 17 (Motors, generators, UPS, Batteries)
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