ETAP 5.0ETAP 5.0
Copyright 2003 Operation Technology, Inc.
Load Flow Analysis
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 2
System ConceptsSystem Concepts
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 3
jQPIV
SS
IVS
LL
LN
+=×=
×=
=
*
13
*1
3
3 φφ
φ
Inductive loads have lagging Power Factors. Capacitive loads have leading Power Factors.
Power in Balanced 3-Phase Systems
Lagging Power Factor Leading Power Factor Current and Voltage
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 4
Leading & Lagging Power Factors
PowerStation displays lagging Power Factors as positive and leading Power Factors as negative. The Power Factor is displayed in percent.
Leading Power Factor
Lagging Power Factor
jQ P +jQ P +jQ P −
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 5
3-Phase Per Unit System
B
2B
B
B
BB
MVA)kV(Z
kV3kVAI
=
=
B
actualpu
B
actualpu
ZZZ
III
=
=
B
actualpu
B
actualpu
SSS
VVV
=
=
=
=
=
=
B
2B
B
B
BB
SVZ
V3SI
ZI3V
VI3S If you have two bases:
Then you may calculate the other two by using the relationships enclosed in brackets. The different bases are:
•IB (Base Current)
•ZB (Base Impedance)
•VB (Base Voltage)
•SB (Base Power)
PowerStation selects for LF:
•100 MVA for SB which is fixed for the entire system.
•The kV rating of reference point is used along with the transformer turnratios are applied to determine the base voltage for different parts of the system.
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 6
Example 1: The diagram shows a simple radial system. PowerStation converts the branch impedance values to the correct base for Load Flow calculations. The LF reports show the branch impedance values in percent. The transformer turn ratio (N1/N2) is 3.31 and the X/R = 12.14
2B
1B kV
2N1NkV =
2
pu
pu
RX1
RXZ
X
+
×
=
Transformer T7: The following equations are used to find the impedance of transformer T7 in 100 MVA base.
=
RX
xR pu
pu
1BkV
2BkV
Transformer Turn Ratio: The transformer turn ratio is used by PowerStation to determine the base voltage for different parts of the system. Different turn ratios are applied starting from the utility kV rating.
To determine base voltage use:
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 7
005336.014.12
06478.0R pu ==06478.0)14.12(1)14.12(065.0X2pu =
+=
The transformer impedance must be converted to 100 MVA base and therefore the following relation must be used, where “n” stands for new and “o” stands for old.
)3538.1j1115.0(5
1005.138.13)06478.0j1033.5(
SS
VVZZ
23
oB
nB
2
nB
oBo
punpu +=
+×=
= −
38.135j15.11Z100Z% pu +=×=
Impedance Z1: The base voltage is determined by using the transformer turn ratio. The base impedance for Z1 is determined using the base voltage at Bus5 and the MVA base.
165608.0100
)0695.4(MVA
VZ22
BB ===0695.4
31.35.13
2N1N
kVV utility
B ==
=
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 8
The per-unit value of the impedance may be determined as soon as the base impedance is known. The per-unit value is multiplied by one hundred to obtain the percent impedance. This value will be the value displayed on the LF report.
)0382.6j6038.0(1656.0
)1j1.0(Z
ZZB
actualpu +=
+==
8.603j38.60Z100Z% pu +=×=
The LF report generated by PowerStation displays the following percent impedance values in 100 MVA base
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 9
Load Flow AnalysisLoad Flow Analysis
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 10
Load Flow Problem• Given
– Load Power Consumption at all buses
– Configuration
– Power Production at each generator
• Basic Requirement– Power Flow in each line and transformer
– Voltage Magnitude and Phase Angle at each bus
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 11
Load Flow Studies• Determine Steady State Operating Conditions
– Voltage Profile– Power Flows– Current Flows– Power Factors– Transformer LTC Settings– Voltage Drops– Generator’s Mvar Demand (Qmax & Qmin)– Total Generation & Power Demand– Steady State Stability Limits– MW & Mvar Losses
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 12
Size & Determine System Equipment & Parameters• Cable / Feeder Capacity• Capacitor Size• Transformer MVA & kV Ratings (Turn Ratios)• Transformer Impedance & Tap Setting• Current Limiting Reactor Rating & Imp.• MCC & Switchgear Current Ratings• Generator Operating Mode (Isochronous / Droop)• Generator’s Mvar Demand• Transmission, Distribution & Utilization kV
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 13
Optimize Operating Conditions• Bus Voltages are Within Acceptable Limits
• Voltages are Within Rated Insulation Limits of Equipment
• Power & Current Flows Do Not Exceed the Maximum Ratings
• System MW & Mvar Losses are Determined
• Circulating Mvar Flows are Eliminated
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 14
Calculation Process
Assume VR
Calc: I = Sload / VR
Calc: Vd = I * Z
Re-Calc VR = Vs - Vd
• Non-Linear System• Calculated Iteratively
– Assume the LoadVoltage (Initial Conditions)
– Calculate the Current I– Based on the Current,
Calculate Voltage Drop Vd– Re-Calculate Load Voltage VR– Re-use Load Voltage as initial condition until the
results are within the specified precision.
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 15
1. Accelerated Gauss-Seidel Method
• Low Requirements on initial values, but slow in speed.
2. Newton-Raphson Method
• Fast in speed, but high requirement on initial values.
• First order derivative is used to speed up calculation.
3. Fast-Decoupled Method
• Two sets of iteration equations: real power – voltage angle, reactive power – voltage magnitude.
• Fast in speed, but low in solution precision.
• Better for radial systems and systems with long lines.
Load Flow Calculation Methods
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 16
Load Nameplate Data
kVkVAFLA
kVkVAFLA
EffPFHP
EffPFkWkVA
Rated
Rated
RatedRated
=
×=
××
=×
=
φ
φ
1
3 3
7457.0
kVkVA1000I
)kV3(kVA1000I
kVAkWPF
)kVar()kW(kVA
1
3
22
×=
××=
=
+=
φ
φ
Where PF and Efficiency are taken at 100 % loading conditions
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 17
Constant Power Loads
• In Load Flow calculations induction, synchronous and lump loads are treated as constant power loads.
• The power output remains constant even if the input voltage changes (constant kVA).
• The lump load power output behaves like a constant power load for the specified % motor load.
Constant Impedance Loads• In Load Flow calculations Static Loads, Lump Loads
(% static), Capacitors and Harmonic Filters and Motor Operated Valves are treated as Constant Impedance Loads.
• The Input Power increases proportionally to the square of the Input Voltage.
• In Load Flow Harmonic Filters may be used as capacitive loads for Power Factor Correction.
• MOVs are modeled as constant impedance loads because of their operating characteristics.
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 19
• The current remains constant even if the voltage changes.
• DC Constant current loads are used to test Battery discharge capacity.
• AC constant current loads may be used to test UPS systems performance.
• DC Constant Current Loads may be defined in PowerStation by defining Load Duty Cycles used for Battery Sizing & Discharge purposes.
Constant Current Loads
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 20
Constant Current Loads
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 21
Generic Loads
Exponential Load
Polynomial Load
Comprehensive Load
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 22
Generator Operation Modes
Feedback Voltage •AVR: Automatic Voltage Regulation•Fixed: Fixed Excitation (no AVR action)
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 23
Governor Operating Modes• Isochronous: This governor setting allows the
generator’s power output to be adjusted based on the system demand.
• Droop: This governor setting allows the generator to be Base Loaded, meaning that the MW output is fixed.
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 24
Isochronous Mode
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 25
Droop Mode
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 26
Droop Mode
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 27
Droop Mode
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 28
Adjusting Steam Flow
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 29
Adjusting Excitation
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 30
In PowerStation Generators and Power Grids have four operating modes that are used in Load Flow calculations.
Swing Mode•Governor is operating in Isochronous mode•Automatic Voltage Regulator
Voltage Control•Governor is operating in Droop Mode•Automatic Voltage Regulator
Mvar Control•Governor is operating in Droop Mode•Fixed Field Excitation (no AVR action)
PF Control•Governor is operating in Droop Mode•AVR Adjusts to Power Factor Setting
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 31
• In the Swing Mode, the voltage is kept fixed. P & Q can vary based on the Power Demand
• In the Voltage Control Mode, P & V are kept fixed while Q & θare varied
• In the Mvar Control Mode, P and Q are kept fixed while V & θare varied
• If in Voltage Control Mode, the limits of P & Q are reached, themodel is changed to a Load Model (P & Q are kept fixed)
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 32
Generator Capability Curve
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 33
Generator Capability Curve
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 34
Generator Capability Curve
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 35
Field Winding Heating Limit
Armature Winding Heating Limit
Machine Rating (Power Factor Point)
Steady State Stability Curve
Maximum & Minimum Reactive Power
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 36
Generator Capability Curve
Field Winding Heating Limit Machine Rating
(Power Factor Point)
Steady State Stability Curve
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 37
Generation CategoriesGenerator/Power Grid Rating Page
Load Flow Loading Page
10 Different Generation Categories for Every Generator or Power Grid in the System
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 38
Power Flow
∠=
∠=
222
111
VV
VV
δ
δ
XV)*COS(
X*VVQ
)(*SINX*VVP
XV)(*COS
X*VVj)(*SIN
X*VV
jQPI*VS
22
2121
2121
22
2121
2121
−−=
−=
−−+−=
+==
δδ
δδ
δδδδ
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 39
Example: Two voltage sources designated as V1 and V2 are connected as shown. If V1= 100 /0° , V2 = 100 /30° and X = 0 +j5 determine the power flow in the system.
I
var536535.10X|I|
268j1000)68.2j10)(50j6.86(IV
268j1000)68.2j10(100IV
68.2j10I5j
)50j6.86(0j100X
VVI
22
*2
*1
21
=×=
−−=+−+=
+−=+−=
−−=
+−+=
−=
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 40
The following graph shows the power flow from Machine M2. This machine behaves as a generator supplying real power and absorbing reactive power from machine M1.
2
1
0
1
Real Power FlowReactive Power Flow
Power Flow1
2−
V E⋅( )X
sin δ ∆( )⋅
V E⋅( )X
cos δ ∆( )⋅V2
X−
π0 δ ∆
S
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 41
Bus VoltagePowerStation displays bus voltage values in two ways
•kV value
•Percent of Nominal Bus kV
%83.97100%
5.13
min
=×=
=
alNo
Calculated
Calculated
kVkVV
kV 8.13min =alNokVFor Bus4:
For Bus5:
%85.96100%
03.4
min
=×=
=
alNo
Calculated
Calculated
kVkVV
kV 16.4min =alNokV
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 42
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 43
Lump Load Negative Loading
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 44
Load Flow Adjustments• Transformer Impedance
– Adjust transformer impedance based on possible length variation tolerance
• Reactor Impedance– Adjust reactor impedance based on specified tolerance
• Overload Heater– Adjust Overload Heater resistance based on specified tolerance
• Transmission Line Length– Adjust Transmission Line Impedance based on possible length
variation tolerance
• Cable Length– Adjust Cable Impedance based on possible length variation tolerance
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 45
Load Flow Study Case Adjustment Page
Adjustments applied
•Individual
•Global
Temperature Correction
• Cable Resistance
• Transmission LineResistance
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 46
Allowable Voltage DropNEC and ANSI C84.1
Power Grid1000 MVAscX/R = 22
Gen110 MWVoltage ControlDesign:%Pf = 85MW = 5 Max Q = 4Min Q = -1
ImpedanceZ113.8 kV 100MVA% Z = 0.01+j1
Load Flow Example 1 Part 1
TransformersT1 = 30 MVAT2 = 15 MVAT3 = 5 MVAT4 = 3 MVASelect typical %Z & X/R
Cable1ICEA 15kV 3/C CU, 100% Size= 250Length= 400 ft
Cable2KERITE 5kV 3/C CU, 100% Size= 500Length= 300 ft
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 48
Load Flow Example 1 Part 2
Cable3ICEA 5kV 3/C CU, 133% Size= 500Length= 100 ft
TransformerT5 = 5 MVASelect typical %Z & X/R
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 49
Load Flow Alerts
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 50
Equipment Overload Alerts
Bus Alerts Monitor Continuous Amps
Cable Monitor Continuous Amps
Reactor Monitor Continuous Amps
Line Monitor Line Ampacity
Transformer Monitor Maximum MVA Output
DC Link DC Link Loading Capability (Idc, Max. MVA)
Panel Monitor Panel Continuous Amps
Generator Monitor Generator Rated MW
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 51
Protective Device Alerts
Protective Devices Monitored parameters % Condition reported
Low Voltage Circuit Breaker Continuous rated Current OverLoadHigh Voltage Circuit Breaker Continuous rated Current OverLoad
Fuses Rated Current OverLoadContactors Continuous rated Current OverLoad
SPDT / SPST switches Continuous rated Current OverLoad
If the Auto Display feature is active, the Alert View Window will appear as soon as the Load Flow calculation has finished.
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 53
Advanced LF TopicsAdvanced LF TopicsLoad Flow Convergence
Voltage Control
Mvar Control
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 54
Load Flow Convergence
• Negative Impedance
• Zero or Very Small Impedance
• Widely Different Branch Impedance Values
• Long Radial System Configurations
• Bad Bus Voltage Initial Values
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 55
Voltage Control
• Under/Over Voltage Conditions must be fixed for proper equipment operation and insulation ratings be met.
• Methods of Improving Voltage Conditions:– Transformer Replacement
– Capacitor Addition
– Transformer Tap Adjustment
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 56
Under-Voltage Example• Create Under Voltage
Condition– Change Syn2 Quantity to 6.
(Info Page, Quantity Field)
– Run LF
– Bus8 Turns Magenta (Under Voltage Condition)
• Method 1 - Change Xfmr– Change T4 from 3 MVA to 8
MVA, will notice slight improvement on the Bus8 kV
– Too Expensive and time consuming
• Method 2 - Shunt Capacitor– Add Shunt Capacitor to Bus8– 300 kvar 3 Banks– Voltage is improved
• Method 3 - Change Tap– Place LTC on Primary of T6– Select Bus8 for Control Bus– Select Update LTC in the
Study Case– Run LF– Bus Voltage Comes within
specified limits
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 57
Mvar Control• Vars from Utility
– Add Switch to CAP1– Open Switch – Run LF
• Method 1 – Generator – Change Generator from
Voltage Control to Mvar Control
– Set Mvar Design Setting to 5 Mvars
• Method 2 – Add Capacitor– Close Switch
– Run Load Flow
– Var Contribution from the Utility reduces
• Method 3 – Xfmr MVA– Change T1 Mva to 40 MVA
– Will notice decrease in the contribution from the Utility
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 58
Panel SystemsPanel Systems
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 59
Panel Boards• They are a collection of branch circuits
feeding system loads
• Panel System is used for representing power and lighting panels in electrical systems
Click to drop once on OLVDouble-Click to drop multiple panels
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 60
RepresentationA panel branch circuit load can be modeled as an internal or external load
Advantages:1. Easier Data Entry2. Concise System
Representation
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 61
Pin AssignmentPin 0 is the top pin of the panelETAP allows up to 24 external load connections
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 62
Assumptions• Vrated (internal load) = Vrated (Panel Voltage)
• Note that if a 1-Phase load is connected to a 3-Phase panel circuit, the rated voltage of the panel circuit is (1/√3) times the rated panel voltage
• The voltage of L1 or L2 phase in a 1-Phase 3-Wire panel is (1/2) times the rated voltage of the panel
• There are no losses in the feeders connecting a load to the panel
• Static loads are calculated based on their rated voltage
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 63
Line-Line ConnectionsLoad Connected Between Two Phases of a3-Phase System
A
BC
Load
IBCIC = -IBC
ABC
LoadB
IB = IBC
Angle by which load current IBC lags the load voltage = θ°
Therefore, for load connected between phases B and C:
SBC = VBC.IBCPBC = VBC.IBC.cos θQBC = VBC.IBC.sin θ
For load connected to phase B
SB = VB.IBPB = VB.IB.cos (θ - 30)QB = VB.IB.sin (θ - 30)
And, for load connected to phase C
SC = VC.ICPC = VC.IC.cos (θ + 30)QC = VC.IC.sin (θ + 30)
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 64
Info Page
NEC SelectionA, B, C from top to bottom or left to right from the front of the panel
Phase B shall be the highest voltage (LG) on a 3-phase, 4-wire delta connected system (midpoint grounded)
3-Phase 4-Wire Panel3-Phase 3-Wire Panel1-Phase 3-Wire Panel1-Phase 2-Wire Panel
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 65
Rating Page
Intelligent kV CalculationIf a 1-Phase panel is connected to a 3-Phase bus having a nominal voltage equal to 0.48 kV, the default rated kV of the panel is set to (0.48/1.732 =) 0.277 kV
For IEC, Enclosure Type is Ingress Protection (IPxy), where IP00 means no protection or shielding on the panel
Select ANSI or IEC Breakers or Fuses from Main Device Library
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 66
Schedule Page
Circuit Numbers with
Standard Layout
Circuit Numbers with Column Layout
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 67
Description TabFirst 14 load items in the list are based on NEC 1999Last 10 load types in the Panel Code Factor Table are user-definedLoad Type is used to determine the Code Factors used in calculating the total panel loadExternal loads are classified as motor load or static load according to the element typeFor External links the load status is determined from the connected load’s demand factor status
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 68
Rating Tab
Enter per phase VA, W, or Amperes for this load.
For example, if total Watts for a 3-phase load are 1200, enter W as 400 (=1200/3)
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 69
Loading Tab
For internal loads, enter the % loading for the selected loading category
For both internal and external loads, Amp values are calculated based on terminal bus nominal kV
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 70
Protective Device Tab
Library Quick Pick -LV Circuit Breaker (Molded Case, with Thermal Magnetic Trip Device) or
Library Quick Pick –Fuse will appear depending on the Type of protective device selected.
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 71
Feeder Tab
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 72
Action ButtonsCopy the content of the selected row to clipboard. Circuit number, Phase, Pole, Load Name, Link and State are not copied.
Paste the entire content (of the copied row) in the selected row. This will work when the Link Type is other than space or unusable, and only for fields which are not blocked.
Blank out the contents of the entire selected row.
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 73
Summary Page
Continuous Load – Per Phase and Total
Non-Continuous Load – Per Phase and Total
Connected Load – Per Phase and Total (Continuous + Non-Continuous Load)
Code Demand – Per Phase and Total
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 74
Output Report
Copyright 2004 Operation Technology, Inc. – Workshop Notes: Load Flow Analysis Slide 75
Panel Code Factors
The first fourteen have fixed formats per NEC 1999
Code demand load depends on Panel Code Factors
Code demand load calculation for internal loads are done for each types of load separately and then summed up
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