Fundamental Design Calculations - Electrical

FUNDAMENTAL ELECTRICAL SYSTEM DESIGN CALCULATIONS AND SYSTEM ARCHITECTURES for Commercial and Residential Buildings

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STANDARD Fundamental Design Calculations Electrical System Rev 00 – November 2011

CONTENTS I.

Design Criteria for Main Equipment Sizing

II.

Low Voltage Wires and Cables

III.

Busduct Sizing

IV.

Overcurrent Protection

V.

Reserved

VI.

Lighting & Power Circuits

VII.

Motor Circuits

VIII.

Fire Pump Motor Circuit

IX.

Power Factor Correction

X.

Basic Panelboard Design

XI.

Standard Electrical System Architecture A. Malls B. BPO C. High Rise Residential

XII.

Reserved

XIII.

Reserved

XIV.

References

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STANDARD Fundamental Design Calculations Electrical System Rev 00 – November 2011

I.

Sizing of Main Equipment A. General Considerations The main equipments for the building’s electrical system are the transformers and generator sets. The sizes of these equipments are determined during the schematic design stage, which depend on load estimate calculation. The load estimate is derived from load densities defined for areas in each type of the building to be designed, which depends on the nature of the building and its corresponding electrical requirement. 1.

Transformers Main transformer is sized based from load estimation after the application of demand factor defined by the designing electrical engineer.

2.

Generator Sets Generator(s), on the other hand, is/are sized depending on building requirement; that is, same size as the main transformer(s) if the building is intended to have 100% backup power. Also, generator sets are sized based on ‘standby’ rating.

Below are the common load groups that are considered in load estimation – 1. 2. 3. 4. 5. 6. 7. 8. 9.

Lighting – Interior, exterior, normal, emergency. Small Power Loads – Receptacle outlets, appliances. Air-conditioning – Chillers, AHU’s, Fans, etc. Plumbing and Sanitation – Domestic pumps, booster pumps, transfer pumps, sump pump, water heaters. Fire protection – Fire pumps, FDAS. Transportation – Elevators, Escalators. Food preparation – Cooking, refrigerating, dishwashing, ovens, etc. Special Loads – Loads in theaters, etc Miscellaneous loads – Auxiliary systems, etc

This design calculation standard will only address the following types of building – 1. 2. 3. 4.

Residential Buildings Malls BPOs Hotels

B. System Voltage Consideration The utilization voltage considered in this design calculation standard is 3-phase, fourwire, 400V / 230 V, 60 Hz. Three phase loads shall be served at 400V, while single phase loads shall be served at 230V line-to-neutral. Primary voltage shall be based from available power utility supply. MAKATI DEVELOPMENT CORPORATION GF, Bonifacio Technology Center st nd 31 Street cor. 2 Avenue, Bonifacio Global City Taguig 1634, Metro Manila, Philippines Tel Nos. (02) 717-5500 to 30 www.mdc.com.ph

STANDARD Fundamental Design Calculations Electrical System Rev 00 – November 2011

C. Prescriptive Design Parameters The load densities to be used in load estimation and initial main equipment sizing will be based from the parameters defined below. These parameters were derived from historical design parameters, code requirements, and actual building performance of existing Ayala buildings. However, the external designer is given liberty to review and adjust these parameters based from his experience. 1. Residential Buildings The load considerations for residential buildings in terms of power are typically the same – household loads and admin/common area loads. Residential (ACCU) Res Units Office Core Areas (Non-AC) Non - food Food Parking

kw / tr 1.3 1.3 n/a 1.3 1.3 n/a

Split-type ACU tr / sqm 0.05 0.06 n/a 0.06 0.10 n/a

pf 0.8 0.8 n/a 0.8 0.8 n/a

A/C Lighting VA / sqm VA / sqm 81 24 90 28 0 4 90 24 163 16 0 4

Receptacle VA / sqm 8 30 4 8 8 4

Misc VA / sqm 37 0 4 0 18 0

Total VA / sqm 150 148 12 122 205 8

2. Malls Load density considerations for malls are – Retail loads (Food and Non-food), and common area / admin loads.

Malls (Chillers) Retail Shop (non-food) Food Banks / Offices Common Areas Parking

Centralized ACU kw / tr tr / sqm 1.26 0.06 1.26 0.10 1.26 0.06 1.26 0.05 n/a n/a

pf 0.8 0.8 0.8 0.8 n/a

A/C Lighting VA / sqm VA / sqm 88 24 158 16 88 28 79 4 0 4

Receptacle VA / sqm 8 8 30 4 4

Misc VA / sqm 0 18 0 4 0

Total VA / sqm 120 200 146 91 8

For developments having a District Cooling System, the chiller loads are not included in the building load estimation. Malls (DCS) Retail Shop (non-food) Food Banks / Offices Common Areas Parking

Centralized ACU kw / tr tr / sqm 0.56 0.06 0.56 0.10 0.56 0.06 0.56 0.05 n/a n/a

pf 0.8 0.8 0.8 0.8 n/a

A/C Lighting VA / sqm VA / sqm 39 24 70 16 39 28 35 4 0 4

Receptacle VA / sqm 8 8 30 4 4

Misc VA / sqm 0 18 0 4 0

Total VA / sqm 71 112 97 47 8

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STANDARD Fundamental Design Calculations Electrical System Rev 00 – November 2011

3. BPO Buildings Design considerations for BPOs are different from typical office buildings. The occupant density is higher for BPOs resulting from higher cooling and power requirement. However, the design for BPO is often just ‘core-and-shell’, since detailed design for tenant spaces are handled by tenants. Therefore, power allotment for tenant units should be carefully considered to anticipate tenant power requirement. Centralized ACU kw / tr tr / sqm 1.26 0.05 1.26 0.10 n/a n/a

BPO (Chillers) Core Areas BPO Offices Parking

pf 0.8 0.8 n/a

A/C Lighting VA / sqm VA / sqm 79 4 158 28 0 4

Receptacle VA / sqm 4 60 4

Misc VA / sqm 4 0 0

Total VA / sqm 91 246 8

For developments having a District Cooling System, the chiller loads are not included in load estimation. BPO (DCS) Core Areas BPO Offices Parking

Centralized ACU kw / tr tr / sqm 0.56 0.05 0.56 0.10 n/a n/a

pf 0.8 0.8 n/a

A/C Lighting VA / sqm VA / sqm 35 4 70 28 0 4

Receptacle VA / sqm 4 60 4

Misc VA / sqm 4 0 0

Total VA / sqm 47 158 8

Centralized ACU kw / tr tr / sqm 1.26 0.05 1.26 0.05 n/a n/a

pf 0.8 0.8 n/a

A/C Lighting VA / sqm VA / sqm 79 4 79 24 0 4

Receptacle VA / sqm 4 8 4

Misc VA / sqm 4 8 0

Total VA / sqm 91 119 8

4. Hotels Hotel Units Core Areas Hotel Units Parking

D. Minimum Demand Factors 1. Residential Buildings a. Residential Loads = Connected Load x 23% (for 62 units or more) b. Admin / Common Area Loads = Connected Load x 70% 2. Malls a. Retail Loads = Connected Load x 70% b. Admin / Common Area Loads = Connected Load x 70% 3. BPO Buildings a. Tenant Areas = Connected Load x 80% b. Common Areas / Admin = Connected Load x 70% 4. Hotels a. Hotel Unit Areas = Connected Load x 60% b. Common Areas / Admin = Connected Load x 70% MAKATI DEVELOPMENT CORPORATION GF, Bonifacio Technology Center st nd 31 Street cor. 2 Avenue, Bonifacio Global City Taguig 1634, Metro Manila, Philippines Tel Nos. (02) 717-5500 to 30 www.mdc.com.ph

STANDARD Fundamental Design Calculations Electrical System Rev 00 – November 2011

II.

Low Voltage Wires and Cables A. Sizing of wires and cables shall be based from the following considerations: 1. Wire/cable sizing should be rated maximum of– a. 100% for non-continuous (cyclic) loads. b. 80% for continuous loads (loads that operate for 3hrs or more). 2. Wire/cable shall be sized to meet Code defined voltage drop limits at its design load current. a. Voltage Drop Considerations Where: VD = Voltage Drop NV = Nominal Voltage at Source I = 1.15* FLC for running condition or I = LRC for starting condition R = DC resistance ohm/305m L = Feeder wire length

3.

Selected wire/cable temperature rating shall be coordinated with all temperature limits, particularly at its terminations. a. Select 60 ˚C temperature rating up to 100A b. Select 75 ˚C temperature rating for more than 100A 4. Wire/cable short circuit withstand current and time shall be coordinated with that of its upstream circuit breakers. B. STANDARD ELECTRICAL WIRING SCHEDULE (Not applicable for motors) Table VII.1 Standard Wiring Schedule for Low Voltage Systems ELECTRICAL WIRING SCHEDULE WIRE SIZE WIRE CODE AMPACITY mm2 3Ø 3W+G 3Ø 4W+G 1Ø 2W+G THWN THHN T0 T1 T2 T3 T4 T5 T7 T8 T9 T10 T11 T12 T13 T14 T15

Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7 Y8 Y9 Y10 Y11 Y12 Y13 Y14

S0 S1 S2 S3 S4 S5 S7 S8 S9 S10 S11 S12 S13 S14 S15

3.5 5.5 8 14 22 30 50 60 80 100 125 150 175 200 250

25 35 50 65 85 110 145 160 195 220 255 280 305 330 375

30 40 55 70 90 115 150 170 205 225 265 295 345 355 400

OCPD AT 20AT 30AT 40AT 50AT 70AT 100AT 125AT 150AT 175AT 200AT 250AT 300AT 400AT

GROUND WIRE mm2 3.5 3.5 5.5 8 8 8 14 22 22 30 30 30 30 30 50

CONDUIT IMC/PVC mm Φ in Φ 15 20 25 25 32 32 50 50 50 65 65 80 80 80 90

1/2 3/4 1 1 1 1/2 1 1/2 2 2 2 2 1/2 2 1/2 3 3 3 3 1/2

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STANDARD Fundamental Design Calculations Electrical System Rev 00 – November 2011

C. Allowable Short Circuit Current Calculation The allowable short circuit current for low-voltage thermoplastic (PVC) insulated wire/cable is given byWhere: Isc = Allowable short circuit current A = cross sectional area of copper conductors, mm2 t =time of short circuit current, seconds K = 104.484, computed constant for thermoplastic copper conductor where the rated wire operating temperature is 75 ˚C and the maximum short circuit temperature is 150 ˚C

Table VII.1 Maximum Short Circuit Withstand of Low Voltage Cables CU WIRE SIZE mm2 3.5 5.5 8 14 22 30 50 60 80 100 125 150 175 200 250

Maximum Short-Circuit Withstand Current in Amperes 1/2 Cycles 4,006 6,295 9,157 16,024 25,180 34,337 57,228 68,674 91,565 114,456 143,071 171,685 200,299 228,913 286,141

1 Cycle 2,833 4,451 6,475 11,331 17,805 24,280 40,466 48,560 64,746 80,933 101,166 121,399 141,633 161,866 202,332

2 Cycles 2,003 3,148 4,578 8,012 12,590 17,168 28,614 34,337 45,783 57,228 71,535 85,842 100,149 114,456 143,071

3 Cycles 1,635 2,570 3,738 6,542 10,280 14,018 23,363 28,036 37,381 46,727 58,408 70,090 81,772 93,453 116,817

4 Cycles 1,416 2,226 3,237 5,665 8,903 12,140 20,233 24,280 32,373 40,466 50,583 60,700 70,816 80,933 101,166

5 Cycles 1,267 1,991 2,896 5,067 7,963 10,858 18,097 21,717 28,955 36,194 45,243 54,291 63,340 72,389 90,486

6 Cycles 1,156 1,817 2,643 4,626 7,269 9,912 16,520 19,824 26,433 33,041 41,301 49,561 57,821 66,081 82,602

D. SIZING OF CONDUITS Percent Conductor Fill formula is given byWhere: D = interior diameter of conduit d = diameter of conductor (wire) n = number of conductors

According to PEC Table 9.1.1.1 the percent fill of (more than two) conductors in a conduit should not exceed 40%.

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STANDARD Fundamental Design Calculations Electrical System Rev 00 – November 2011

III.

BUSDUCT SYSTEM Busduct system shall be considered to be used for main feeders and risers. Busduct may be of copper or aluminum conductor material; whichever the project budget dictates. A. Busduct Sizing shall be based on the following considerations – 5. 6. 7. 8. 9.

IV.

The voltage rating of the busduct shall be 600V. The busduct rating shall not be less than the demand load to be served. Voltage drop not exceeding 2% shall be considered in sizing the busduct. The ambient temperature consideration in sizing the busduct shall be 40°C. The kAIC rating of busduct shall be selected to withstand the maximum available short circuit current and shall be coordinated with that of its upstream OCPD.

Overcurrent Protection not over 600V Circuit Breakers shall be the standard overcurrent protective devices of equipment and conductors for low voltage systems. Air Circuit Breakers shall be used for main switchgears and synchronizing panels. Molded Case Circuit Breakers shall be used for distribution, power, and lighting panelboards. A. Sizing of Circuit Breakers shall be based from the following considerations: 1. The next higher size of circuit breaker above the ampacity of the conductors being protected shall be permitted up to 800A circuit breaker rating except – a. The conductors being protected supply branch circuit muti-outlet receptacles. b. The conductors being protected supply motor branch circuit. 2. Where the circuit breaker exceeds rating over 800A, the ampacity of the conductor it protects shall be equal or greater than the rating of the circuit breaker. 3. The interrupting capacity of the circuit breaker shall be greater than the maximum available three-phase short circuit current.

V.

Reserved

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STANDARD Fundamental Design Calculations Electrical System Rev 00 – November 2011

VI.

LIGHTING AND RECEPTACLE OUTLET CIRCUIT A. Lighting Circuits 1.

2. 3.

Individual lighting circuit shall be sized on the maximum of 2500VA. a. If not otherwise specified, each lighting fixture shall be assumed with a minimum of 100VA rating. b. A voltage drop not exceeding 3% shall be considered in each branch circuit. Lighting circuit installation shall be in accordance with PEC. Lighting system design criteria shall be based on Ayala Land Inc. Building Standards.

B. Receptacle Outlet Circuits 1.

2.

Individual receptacle outlet circuit shall be sized on the maximum of 1800VA. a. Each receptacle outlet shall be assumed with a minimum of 180VA rating. b. A voltage drop not exceeding 3% shall be considered in each branch circuit. Receptacle outlet circuit installation shall be based on PEC and Ayala Land Inc. Building Standards.

INTENTIONALLY LEFT BLANK

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STANDARD Fundamental Design Calculations Electrical System Rev 00 – November 2011

VII.

MOTOR ELECTRICAL DESIGN (NOT applicable for fire pump motor) A. Motor Electrical System Design shall be based on the following considerations: 1. Size the branch circuit wire not less than 125% of the PEC-defined motor full load current. a. Since the operating temperature of motors is above 30°C (i.e., mostly 40°C) , the branch circuit wire shall be coordinated to this temperature rating, by dividing the PEC-defined motor full load current to the ambient temperature correction factor, then sizing the branch circuit wire using this corrected ampacity. 2. Size the motor disconnect not less than 115% of the PEC defined motor full load current. For uniformity, the size of motor disconnect shall be equal to the ampacity of the branch circuit wire. 3. From PEC Table 4.30.4.2 size the Inverse time circuit breaker OCPD at 250% of the PEC defined motor full load current. 4. Motor controller, including overload protection will be the scope of Mechanical / Sanitary contractor, subject to Electrical Design Engineer’s review. Table VII.1 Motor Electrical System Design, Sizing of Feeders and Circuit Breakers Motor HP hp 1/2 3/4 1 1 1/2 2 3 5 7 1/2 10 15 20 25 30 50 60 75 100 125 150 200 250 300

Full Load Currents, 3Φ 230V 400V 460V 2.2 1.3 1.1 3.2 1.8 1.6 4.2 2.3 2.1 6 3.3 3 6.8 4.3 3.4 9.6 6.1 4.8 15.2 9.7 7.6 22 14 11 28 18 14 42 27 21 54 34 27 68 44 34 80 51 40 130 83 65 154 103 77 192 128 96 248 165 124 312 208 156 360 240 180 480 320 240 403 302 482 361

230V 3.5mm2 3.5mm2 3.5mm2 3.5mm2 3.5mm2 3.5mm2 5.5mm2 8.0 mm2 8.0 mm2 22 mm2 30 mm2 38 mm2 38 mm2 80 mm2 100 mm2 150 mm2 250 mm2 2-125mm1 2-150mm2 2-250mm2

SIZE OF WIRES 400V 3.5mm2 3.5mm2 3.5mm2 3.5mm2 3.5mm2 3.5mm2 3.5mm2 5.5mm2 5.5mm2 8.0 mm2 14 mm2 22 mm2 30 mm2 50 mm2 50 mm2 80 mm2 125 mm2 200 mm2 250 mm2 2-125mm2 2-200 mm2 2-250mm2

460V 3.5mm2 3.5mm2 3.5mm2 3.5mm2 3.5mm2 3.5mm2 3.5mm2 3.5mm2 5.5mm2 5.5mm2 8.0 mm2 14 mm2 22 mm2 38 mm2 38 mm2 50 mm2 80 mm2 125 mm2 125 mm2 250 mm2 2-125mm2 2-150 mm2

230V 20AT 20AT 20AT 20AT 20AT 30 AT 40 AT 70AT 70AT 100 AT 150 AT 175 AT 200 AT 400 AT 400 AT 500 AT 800 AT 800 AT 1000 AT 1200 AT

SIZE OF ITCB 400V 20AT 20AT 20AT 20AT 20AT 20AT 30 AT 40 AT 50 AT 70AT 100 AT 125 AT 125 AT 200 AT 300 AT 400 AT 500 AT 600 AT 600 AT 800 AT 1000 AT 1200 AT

460V 20AT 20AT 20AT 20AT 20AT 20AT 20AT 30 AT 40 AT 70AT 70AT 100 AT 100 AT 175 AT 200AT 250 AT 400 AT 400 AT 500 AT 500 AT 800 AT 1000 AT

*Based from PEC 4.30.14.4

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STANDARD Fundamental Design Calculations Electrical System Rev 00 – November 2011

B. Airconditioning and Refrigerating Equipment Electrical System Design shall be based on the following considerations: 1. Size the branch circuit wire not less than 125% of the motor – compressor rated – load current or the branch – circuit selection current, whichever is greater. a. Since the operating temperature of motors is above 30°C (i.e., mostly 40°C) , the branch circuit wire shall be coordinated to this temperature rating, by dividing the motor – compressor rated – load current to the ambient temperature correction factor, then size the branch circuit wire using this corrected ampacity. 2. Size the motor disconnect not less than 115% of the motor – compressor rated – load current. For uniformity, the size of motor disconnect shall be equal to the ampacity of the branch circuit wire. 3. From PEC Table 4.30.4.2 size the Inverse time circuit breaker OCPD at 250% of the motor – compressor rated – load current. 4. Motor controller, including overload protection will be the scope of Mechanical / Sanitary contractor, subject to Electrical Design Engineer’s review.

INTENTIONALLY LEFT BLANK

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STANDARD Fundamental Design Calculations Electrical System Rev 00 – November 2011

VIII.

DESIGN FOR MOTOR DRIVEN FIRE PUMP SYSTEM B. Fire Pump Electrical System shall be designed to meet the following requirements, as defined in the Philippine Electrical Code: 1. Dedicated overcurrent protective device (OCPD) and disconnecting means must be sized to indefinitely carry the locked-rotor current of the fire pump motor(s) and associated pump(s). 2. The circuit components serving the fire pump must be chosen to withstand the available short circuit current at the point of installation. 3. Fire pump feeder must be sized to have an ampacity of not less than 125% of the full load current of the fire pump motor(s) and pressure maintenance motor(s), considering – a. The feeder conductor ampacity shall be corrected to coordinate with the fire pump motor’s design ambient temperature. b. The voltage at the fire pump controller terminal shall not drop more than 15% below nominal voltage during starting conditions. c. The voltage at the fire pump controller terminal shall not drop more than 5% below the nominal voltage during running conditions when the motor is operating at 115% of its full load current (capacity). Table VII.1 Firepump Electrical System Design, Sizing of Feeders and Circuit Breakers Firepump Motor Full Load Locked Rotor Rated Current* Current 380V** Horsepower hp Amp Amp 20 34 204 25 44 264 30 51 306 40 66 396 50 83 498 60 103 618 75 128 768 100 165 990 125 208 1248 150 240 1440 200 320 1920 250 403 2418 *Based from PEC 4.30.14.4 **Assumed 6-times the motor full load current

Size of OCPD

Size of Feeder

Maximum Circuit Length

AT 200 250 300 400 500 600 800 1000 1200 1600 2000 3000

sq.mm. 30 30 30 50 50 60 80 125 200 250 2-150 2-200

m 300 300 300 300 300 300 300 400 400 400 500 500

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STANDARD Fundamental Design Calculations Electrical System Rev 00 – November 2011

C. Schematic Design for Fire Pump Normal Power Source Feeder Redundant Power Source Feeder (in separate route) Fire Pump ATS Feeder Tap for Jockey Pump Fire Pump Motor Controller

Fire Pump Motor Jockey Pump Motor

D. Design Calculation Example A 150hp Nema Design B fire pump motor has a full load current of 240Amp. Its associated pressure maintenance pump is rated 5hp having a full load current of 9.7Amp. The maximum ambient operating temperature is 40°C. The power supply is 400V, 3Φ, 60hz. a. Sizing of feeder wire to the fire pump controller 150hp, 380V, 3Φ FLC 240A x 1.25 = 300A 5hp, 380V, 3Φ FLC 9.70A x 1.25 =12.13A Total FLC =312.13A, say 312A And so, the minimum ampacity of feeder conductors is 312A. Correcting the conductor ampacity to 40°C by dividing 0.88, we yield 354A. Using 75˚C temperature rating of 600V rated building wires; a 250mm2 copper conductor is the minimum size as per PEC Table 3.10.1.16

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STANDARD Fundamental Design Calculations Electrical System Rev 00 – November 2011

b. Voltage Drop Considerations Where: VD = Voltage Drop NV = Nominal Voltage at Source I = 1.15* FLC for running condition or I = LRC for starting condition R = DC resistance ohm/305m L = Feeder wire length

Using the above formula, the feeder wire, 200mm2 copper conductor, must not exceed 200m length to satisfy both motor starting and running voltage drop limitations. c. Sizing of OCPD and ATS 150hp, 380V, 3Φ FLC 240A x 6 = 1,440A (locked rotor current) 5hp, 380V, 3Φ FLC 9.70A x 6 = 58.20A Total RLC =1,498.20A say, 1,498A And so, the total locked rotor current is 1,498A, assuming Nema Design B code F. The next higher standard size of OCPD (circuit breaker) and ATS is 1600AF/AT

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STANDARD Fundamental Design Calculations Electrical System Rev 00 – November 2011

IX.

CAPACITOR BANK SIZING A. Capacitor Bank design shall satisfy the following basic considerations: 1. The size of the capacitor bank should be able to correct system power factor from 0.8 to 0.95. 2. The ampacity of the capacitor feeder conductor shall not be less than 135% of the rated current of the capacitor. 3. The capacitor bank shall be provided with a means of discharging stored energy. 4. Capacitor bank specification must consider harmonic in selecting the type of capacitor, and contactor switches.

Table VIII.1 Capacitor Bank Sizing based from Main Transformer Sizes Nominal Transformer Rating 300 500 750 1000 1500 2000 2500 3000

Power Factor Before Compensation 0.8 0.8 0.8 0.8 0.8 0.8 0.8 0.8

Power Factor After Compensation 0.95 0.95 0.95 0.95 0.95 0.95 0.95 0.95

Nominal Capacitor Bank Rating 100 150 250 300 450 600 750 900

B. Schematic Design of Capacitor Bank

To Low Voltage Switchgear Capacitor Feeder Capacitor Overcurrent Protection Discharge Resistor

Capacitor Bank

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STANDARD Fundamental Design Calculations Electrical System Rev 00 – November 2011

C. Design Calculation Procedure Calculate the size of capacitor bank in a 1MVA electrical system, to be able to correct the system power from 0.8 to 0.95.

Based from the power triangle, S = 1000 KVA Cos Φ1 = 0.8 ; Φ1 = 36.87° Cos Φ2= 0.95 ; Φ2 = 18.19° Also, Sin Φ1 = Q1/S Q1 = S*sinΦ1 Q2 = S*sinΦ2

Solving for Qc, Qc = Q1 - Q2 Qc = S (sinΦ1 - sinΦ2) = 1000(0.6 - 0.312) Qc = 288 KVAR say, 300kVAR

And so, the rating of the capacitor is 300kVAR. Selecting capacitor sensitivity of 5%15%, provide 6 – steps of 50kVAR.

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STANDARD Fundamental Design Calculations Electrical System Rev 00 – November 2011

X.

PANELBOARD DESIGN 400 / 230V Systems A. Design Load Schedule for 3-phase 400 / 230V System

PANEL FED FROM

: :

DP-TEMPLATE (ENCODE PANEL SOURCE)

MAIN CIRCUIT BREAKER MAIN FEEDER SIZE SYSTEM VOLTAGE

: : :

100 Y4 230

3Ø

VOLTAMPERE

AF 80 (SEE WIRING LEGEND) VOLTS

BRANCH AMPERE LOAD CKT NO. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

LOAD DESCRIPTION (Encode Loads) (Encode Loads) (Encode Loads) (Encode Loads) (Encode Loads) (Encode Loads) (Encode Loads) (Encode Loads) (Encode Loads) (Encode Loads) (Encode Loads) (Encode Loads)

ØAN

ØBN

ØCN

BRANCH CIRCUIT BREAKER

12.00 8.00

2,760 1,840 1,500 1,500 2,300 2,760 1,150 1,380 1,840 1,840 2,300 2,300

6.52 6.52 10.00 12.00 5.00 6.00 8.00 8.00 10.00 10.00 -

TOTAL CONNECTED LOAD: LOCATION ENCLOSURE MOUNTING

: : :

31.00

29.04

42.00

0.00

(ENCODE PANEL LOCATION) (ENCODE TYPE OF ENCLOSURE, NEMA RATING) (SURFACE, FREE-STANDING, FLUSH-MOUNTED, ETC)

AT, 3-POLE, CENTER MAIN

BRANCH CIRCUIT WIRING

POLE

AMPEREFRAME

AMPERETRIP

CODE

WIRE

1P 1P 1P 1P 1P 1P 1P 1P 1P 1P 1P 1P 1P 1P 1P 1P 1P 1P

50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50

30 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20

S1 S0 S0 S0 S0 S0 S0 S0 S0 S0 S0 S0 S0 S0 S0 S0 S0 S0

THWN THWN THWN THWN THWN THWN THWN THWN THWN THWN THWN THWN THWN THWN THWN THWN THWN THWN

: : :

80

RACEWAY PVC SCH PVC SCH PVC SCH PVC SCH PVC SCH PVC SCH PVC SCH PVC SCH PVC SCH PVC SCH PVC SCH PVC SCH PVC SCH PVC SCH PVC SCH PVC SCH PVC SCH PVC SCH

40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40

23,469 MAIN CB KAIC RATING BRANCH CB KAIC RATING APPLIED DEMAND FACTOR

kAIC kAIC %

Table IX.1 Load Schedule Template 3-phase 400 / 230V System

B. Three-Phase 4-wire + ground 400V / 230V Systems To 400V 4W+G 3-phase Source

3-Pole Main Circuit Breaker

to 400V 3-phase Loads, other panelboards, etc. to 230V single-phase Loads

ΦA ΦB ΦC

N G

MAKATI DEVELOPMENT CORPORATION GF, Bonifacio Technology Center st nd 31 Street cor. 2 Avenue, Bonifacio Global City Taguig 1634, Metro Manila, Philippines Tel Nos. (02) 717-5500 to 30 www.mdc.com.ph

STANDARD Fundamental Design Calculations Electrical System Rev 00 – November 2011

XI.

STANDARD SYSTEM ARCHITECTURE

MAKATI DEVELOPMENT CORPORATION GF, Bonifacio Technology Center st nd 31 Street cor. 2 Avenue, Bonifacio Global City Taguig 1634, Metro Manila, Philippines Tel Nos. (02) 717-5500 to 30 www.mdc.com.ph

STANDARD Fundamental Design Calculations Electrical System Rev 00 – November 2011

MAKATI DEVELOPMENT CORPORATION GF, Bonifacio Technology Center st nd 31 Street cor. 2 Avenue, Bonifacio Global City Taguig 1634, Metro Manila, Philippines Tel Nos. (02) 717-5500 to 30 www.mdc.com.ph

STANDARD Fundamental Design Calculations Electrical System Rev 00 – November 2011

MAKATI DEVELOPMENT CORPORATION GF, Bonifacio Technology Center st nd 31 Street cor. 2 Avenue, Bonifacio Global City Taguig 1634, Metro Manila, Philippines Tel Nos. (02) 717-5500 to 30 www.mdc.com.ph

STANDARD Fundamental Design Calculations Electrical System Rev 00 – November 2011

MAKATI DEVELOPMENT CORPORATION GF, Bonifacio Technology Center st nd 31 Street cor. 2 Avenue, Bonifacio Global City Taguig 1634, Metro Manila, Philippines Tel Nos. (02) 717-5500 to 30 www.mdc.com.ph

STANDARD Fundamental Design Calculations Electrical System Rev 00 – November 2011

XII.

Reserved

XIII.

Reserved

XIV.

References

MAKATI DEVELOPMENT CORPORATION GF, Bonifacio Technology Center st nd 31 Street cor. 2 Avenue, Bonifacio Global City Taguig 1634, Metro Manila, Philippines Tel Nos. (02) 717-5500 to 30 www.mdc.com.ph

STANDARD Fundamental Design Calculations Electrical System Rev 00 – November 2011

Prepared by:

Nathaniel S. Acosta Technical Services Engineer

Noted by:

Approved by:

Artemio C. Pugat Jr. Electrical Section Head

Roger N. Tiguelo CG-MEPF Head

MAKATI DEVELOPMENT CORPORATION GF, Bonifacio Technology Center st nd 31 Street cor. 2 Avenue, Bonifacio Global City Taguig 1634, Metro Manila, Philippines Tel Nos. (02) 717-5500 to 30 www.mdc.com.ph