Calculation for Generator sizing Procedure The generator sizing is done based on the following conditions. a) Load Calculate from continuous. b) 10 % spare capacity for future loads. A) Calculation of total load: Total connected load as per load summary given below. (Refer to generator sizing-load-summary details ) Continuous Load Total KW 237.22 Total KVAR 0.00 Total KVA 279.08 Minimum KW =237.22 KW Maximum KVA =279.08 B) Calculation for Generator Capacity Generator Capacity (In KVA) =Maximum Load X 1.1 = 306.99 KVA (Considering 10% spare capacity for future loads) So we select…

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## How to select a transformer sizing or rating for commercial and industrial ?

Calculate Transformer sizing and Voltage drop with regulation at starting of large size motor Procedure:- The transformer sizing is done base on the following condition. a) peak load calculated from continuous ,intermittent & standby. b) 10% spare capacity for future loads. c) Load requirement with highest rated Motor started on DOL. 1:-Calculation of total peak load Total connected load as per transformer-sizing-load-summary given below Continuous load (E) Intermittent load (F) Stand by load (G) Total KW 222.74 Total kVR 138.04 Total KVA 262.05 Total KW 1871.61 Total KVAR 1159.92 Total…

Read More## How to calculate electrical fault or Short circuit current?

Short circuit current calculation. Purpose It plays a very important role to protect & also safety of commercial and industrial electrical equipment like circuit breakers,transformers …etc. What is short circuit current? When two or more conductors are different phases come in contact with each other in a line, transformer or any other power element, then the part of the impedance is shunted out of the circuit due to which a large current flow in the un-faulted phases, such current is called the short circuit current. It reduces the effect of impedance in…

Read More## How to choose high voltage cable size?

Calculation of nominal cross sectional area of the high voltage cable High voltage cable The cross sectional area of high voltage cable where calculated shall not be less the value determined by following formula:- S = (I SC *√t ) / K Where, S= Nominal cross sectional area of the conductor in mm2 I SC = Value of fault current or short circuit current in KA T=Fault clearing…

Read More## How to calculate LT Cable Size and Voltage drop in Electrical Installation?

Cable size and Voltage drop calculation for LT / LV (Low tension/Low voltage) Purpose The purpose of this document is lay to down the guidelines and design procedure for performing the LV cable size and voltage drop calculation. Relevant IS standards:- IS:694/1990 for PVC cable IS:1554 part-1/ 1998 for heavy-duty PVC cable IS: 7098 part-1 /1988 for XLPE cable Procedure The cable size is selected base on the four following consideration:- Cable Derating Amp should be higher than Full Load Current of Load. Cable voltage drop should be less than…

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