Calculating electricity costs for electric centrifugal pumps

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Calculating electricity costs for electric centrifugal pumps

How to calculate electricity costs for motors and electric centrifugal pumps                                            

Calculation formula              
Electrical power ( KW.)  =   Operating current ( A.) x Operating voltage ( V.)         
Electricity cost (baht) = Electrical power ( KW.) x electricity tariff per unit (baht)                  
Principle of electricity cost calculation    is 1 Kw ( kilowatt) = 1 unit          
     For 220 V.      transformer 5 A. ( amperes), per unit 4.1 baht per hour + FT+ VAT ( value-added tax)          
     ==>> This price may differ; compare it with the electricity bill for the relevant area.          
transformer 15 A. ( amperes), per unit 4.6 baht per hour + FT+VAT ( value-added tax)     
     ==>> This price may differ; compare it with the electricity bill for the relevant area.                 
For 380 V. per unit 4.2 baht per hour + VAT ( value-added tax)     
     ==>> This price may differ; compare it with the electricity bill for the relevant area.                
Calculation method              
Commonly encountered values are          
Motor 1 HP draws a current of 5 A. ( calculated while the motor is running)          
Motor 2 HP draws a current of 10 A. ( calculated while the motor is running)          
Motor 3 HP draws a current of 15 A. ( calculated while the motor is running)                
Example          
water pump model WC200 (2" 2HP) draws an electrical current of 10 A. used with a supply of 220 V. electrical transformer 15A.                  
From the formula    Electrical power ( KW.)  =   Operating current ( A.) x Operating voltage ( V.)     
Electrical power ( KW.)      =   10A. x 220V.     
                                      =   2,200V.     
Electrical power ( KW.)      =   2.2KW.      ======>> A                
Electricity cost (baht)          =   Electrical power ( KW.) x electricity tariff per unit (baht)     
Electricity cost (baht)          =   2.2KW x 4.6 baht per hour          
                                     =   10.12 baht per hour ======= >> B             
Normally, we count only the time when the water pump operates, which is 4 - 6 hours per day                
Daily electricity cost (baht) = 10.12 baht per hour x 6 hours     
                                         =   60.72 baht per day             
Monthly electricity cost (baht) = 60.72 baht per day x 30 days     
                                            =   1,821.6 baht + VAT (7%)         
Therefore:    Monthly electricity cost (baht) = 1,949.11 baht per month, including value-added tax