tennee2007
Electrical
- Jun 4, 2007
- 5
I have a question regarding sizing a standby, diesel generator for a hospital.
Typically, I total up the total KVA load connected to the generator, add 20% to the load (assuming no future capacity needed) and size the generator to the next larger KVA size. For example, if the total load on the generator is 468 KVA, add 20% is 561.6 KVA, so I might pick a 500 KW/625 KVA generator. The voltage is 480/277 volt, 3 phase 4 wire.
Now, I KNOW that the actual load the generator will "see" is less than the 468 KVa, because of diversity, motors not running fully loaded, receptacles not being used, etc.
So, here is my question: Assuming the 468 KVa load is 150 KVa of motors, 100 KVa of lighting and the balance (218 KVa) is receptacles, misc loads, etc. how would you aize the generator? (Assume we are not in California, where you have to size to connected load).
Thx.
Typically, I total up the total KVA load connected to the generator, add 20% to the load (assuming no future capacity needed) and size the generator to the next larger KVA size. For example, if the total load on the generator is 468 KVA, add 20% is 561.6 KVA, so I might pick a 500 KW/625 KVA generator. The voltage is 480/277 volt, 3 phase 4 wire.
Now, I KNOW that the actual load the generator will "see" is less than the 468 KVa, because of diversity, motors not running fully loaded, receptacles not being used, etc.
So, here is my question: Assuming the 468 KVa load is 150 KVa of motors, 100 KVa of lighting and the balance (218 KVa) is receptacles, misc loads, etc. how would you aize the generator? (Assume we are not in California, where you have to size to connected load).
Thx.