2nd Day (6th April 2010 / Tuesday)
Now is my 2nd day of training..
Last night I went to bed a bit late made me feel so tired for my whole day till now..=.=”
But lucky I still manage to woke up early morning (Helmi woke me up act), so I check in on time…again..^_^
So, for today, I continue analyzing the drawing that had been given yesterday..
And today, I do more on calculation, Load Demand Calculation..
The objectives of this load demand calculation is:
1) To estimates the overall power demand for the whole developments
2) To determined the required quantity of power sub-station in the whole developments
3) To determined the cables size and rating of transformers.
To start it, first I need to do low voltage calculation, which I need to calculate the power needed for each unit of every department apartment type A, type B and type AB. And then, I need to apply diversity factor to find the maximum demand (MD).
Diversity Factor is a factor that has been declared in British Standard (BS) but no value mentioned. It’s up to designer to put the value for the diversity factor based on his/her experience. Diversity factor is very important in calculation of power demand because we can minimize power usage and make it balance and cut the cost of maintenance. On the other word, we can say the diversity factor as a usage level.
Here is some example:
· At your home, you would have lamp, fan, television, radio, refrigerator, washing machine and so on, but you would never turn on everything at the same time, when you are watching television, you turn off the radio, when nobody in the kitchen, you turn off the light at the kitchen. What I can say here is, it’s not like using the electricity at maximum rate 24 hours per day, and 7 days per week.
· Next, if you are living at apartment, there would be several unit at the same building, let’s say 16 units for each building, there are no necessary that all the unit use the same electricity at the same time. Perhaps some of them are on holiday, so they use the lower rate of electricity than the other.
In conclusion, important of diversity factor is can optimize the electricity usage and make it longer lifetime and reduce the maintenance cost…