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3. Calculate Size of Diesel Generator Set

CALCULATE SIZE OF DIESEL GENERATOR FOR VARIOUS TYPES OF LOAD

June 21, 2024 Leave a comment

Calculate Size of Diesel Generator set for following types of various equipment’s

D.G Set Detail:

  • G Set Phase-Phase Voltage=415V, Phase-Neutral Voltage=230V, Future Load expansion=10%, D.G overload capacity =130%.

Connected Load:

  1. Fire Fighting Pump: 1No,3 Phase, 90KW, starting P.F is 0.7 & running P.F is 0.8, Soft Starter, Continuous use. 2. HVAC Load: 1No, 3 Phase, 20KW, starting P.F is 0.7 & running P.F is 0.8, Intermediate use. 3. UPS Load: 1No, 3 Phase, 7KW, starting P.F is 0.7 & running P.F is 0.8, Continuous use. 4. Lighting Load: 10No, 1Phase ,400Watt, starting P.F is 0.7 & running P.F is 0.8, Continuous use.
  • Linear Load =General Electrical equipment, Heater * Non-Linear Load = UPS, Inverter, Ballast, Drives

CALCULATION:

LOAD NO:1 (MOTOR LOAD)

  • Total Load (KW)= No of Equipment X Size of Equipment * Total Load (KW)=01×90 =90KW * Diversify Load (KW)= Total Load X Duty factor (0=Stand by Load,1=continuous Load, 0 to 1 =Intermediate Load) * Diversify Load (KW) = 90×1= 90KW————————————–(1) * Running KVA = Diversify Load (KW) / Running P.F * Running KVA = 90 x 0.8 * Running KVA =113 KVA————————————–(2) * Running Amp (Amp) = Diversify Load (KW) / 1.732 x Volt x Running P.F * Running Amp (Amp) =90×1000 / 1.732 x 415 x 0.8 * Running Amp (Amp) =156.7 Amp * Starting Amp = Running Amp X Multiplying Factor of Starter * Multiplying Factor of Starter is as under.

Starter Starting current Method Starting current Direct-on-Line (DOL) 5 to 10 times the full load current Star-Delta Starter 3 to 4 times the full load current Auto-transformer 2 to 3 times the full load current Soft starter 1.1 to 2 times full load current Variable Speed drive 1.1 to 1.5 times full load current

  • Considering Multiplying Factor for Soft Starter is 2 * Starting Amp = 156.7 X 2 * Starting Amp =313Amp * Starting KVA = (Diversify Load (KW) / Starting P.F) X Multiplying Factor of Starter * Starting KVA = (90/0.7) X 2 * Starting KVA = 257 KVA——————————————–(3)

LOAD NO:2 (HVAC LOAD)

  • Total Load (KW)= No of Equipment X Size of Equipment * Total Load (KW)=01×20 =20KW * Diversify Load (KW)= Total Load X Duty factor (0=Stand by Load,1=continuous Load, 0 to 1 =Intermediate Load) * Diversify Load (KW) = 20×0.8= 16KW————————————–(4) * Running KVA = Diversify Load (KW) / Running P.F * Running KVA = 16 x 0.8 * Running KVA =20 KVA————————————–(5) * Running Amp (Amp) = Diversify Load (KW) / 1.732 x Volt x Running P.F * Running Amp (Amp) =16×1000 / 1.732 x 415 x 0.8 * Running Amp (Amp) =28 Amp * Starting Amp = Running Amp X Multiplying Factor of HVAC * Multiplying Factor of Starting Current for various type of Load is as under.

Starting current

Type of Load Starting current for Load Linear 1 time the full load current Non-Linear 1.2 to 1.6 times the full load current HVAC 1.2 to 1.5 times the full load current

  • Considering Multiplying Factor of HVAC is 1.3 * Starting Amp = 28X 1.3 * Starting Amp =36Amp * Starting KVA = (Diversify Load (KW) / Starting P.F) X Multiplying Factor of HVAC * Starting KVA = (16/0.7) X1.3 * Starting KVA = 30 KVA——————————————–(6)

LOAD NO:3 (NON-LINEAR LOAD)

  • Total Load (KW)= No of Equipment X Size of Equipment * Total Load (KW)=01×7 =7KW * Diversify Load (KW)= Total Load X Duty factor (0=Stand by Load,1=continuous Load, 0 to 1 =Intermediate Load) * Diversify Load (KW) = 7×1= 7KW————————————–(7) * Running KVA = Diversify Load (KW) / Running P.F * Running KVA = 7 x 0.8 * Running KVA =9 KVA————————————–(8) * Running Amp (Amp) = Diversify Load (KW) / 1.732 x Volt x Running P.F * Running Amp (Amp) =7×1000 / 1.732 x 415 x 0.8 * Running Amp (Amp) =12 Amp * Starting Amp = Running Amp X Multiplying Factor of Non-Linear Load * Multiplying Factor of Starting Current for various type of Load is as under.

Starting current

Type of Load Starting current for Load Linear 1 time the full load current Non-Linear 1.2 to 1.6 times the full load current HVAC 1.2 to 1.5 times the full load current

  • Considering Multiplying Factor of Non-Linear Load (UPS) is 1.6 * Starting Amp = 12X 1.6 * Starting Amp =19Amp * Starting KVA = (Diversify Load (KW) / Starting P.F) X Multiplying Factor of HVAC * Starting KVA = (7/0.7) X1.6 * Starting KVA = 16 KVA——————————————–(9)

LOAD NO:4 (LINEAR LOAD)

  • Total Load (KW)= No of Equipment X Size of Equipment * Total Load (KW)=10×0.4 =4KW * Diversify Load (KW)= Total Load X Duty factor (0=Stand by Load,1=continuous Load, 0 to 1 =Intermediate Load) * Diversify Load (KW) = 4×1= 4KW————————————–(10) * Running KVA = Diversify Load (KW) / Running P.F * Running KVA = 4 x 0.8 * Running KVA =5 KVA————————————–(11) * Running Amp (Amp) = Diversify Load (KW) / 1.732 x Volt x Running P.F * Running Amp (Amp) =4×1000 / 230 x 0.8 * Running Amp (Amp) =22 Amp * Starting Amp = Running Amp X Multiplying Factor of …