urgent help needed in sizing the generator

[vipin]

Hi friends

i have some difficult comments for my selection of generator for one of my client..

i ll give the details here

i have a main panel at 462kw to be fed with a generator

connected load = 462kw

diversified load = 371kw (made from detailed calculation of all the feeders)

spare required= 20 % of connected load =92.4kw

total anticipated load on genset = diversified load + spare =371+92.4= 463.4kw

here all the equipments are kitchen equipments and there is no heavy motors involved in the project.....we can take almost 85 to 90% pf.

i ve selected a 725kva prime generator, but my main contractor says it is insufficient as the genset can be selected based on 70% of its capacity due to ios regulations. can some body help me to justify this, coz we ve already purchased the 725kva x 2 nos for duty standby operation..... the standby rating of the same genset is 800kva .

 

[Andy™]

contact where your getting the genny from. they will be able to help much better

 

[steptoe]

gennys should be total load + 80% and no diversity allowed.

well that is what I was taught anyway,

unless you have motors fitted, then it is the total running load plus 100% of the start up load of the largest rated motor + 25%

thats just an old basic rule of thumb from the jurassic period though,

its probably a lot different nowadays.

 

[Larnacaman]

Running generators at less than 60/70% of it's rated load capacity, and you will be effectively destroying your gen-set motor. Genny's like load!!

When a generator has been woefully over sized you end-up having to install load banks to keep it topped up with to at least the minimum load recommended by the manufacturer.

....So take Andy's advice and contact them, giving full information of your needs and requirements. Which in all honestly, you should have done as part of the tender prior to purchasing....