http://cr4.globalspec.com/comment/860909

http://cr4.globalspec.com/comment/860805

What makes you think a 200 KVA generator set has a maximum single load of 40 KVA? What do you mean by 'single load'? There is obviously more significant information that you haven't shared with us.

Think along the lines of what a DOL motor does when its starts up. The short term load can be 6 x FLC. Think what this might do to the DG - its going to sink it.

It a rule of thumb but as a single inductive load don't go more than 25% of gen set rating.

You need to be aware of potential brown outs when you start a large motor that might upset computers and sensitive kit.

Horrible loads include motors, SON lamps, welders etc.

Its an inexact science.

thanx silverfox

but it appears as 20% because 40 kVA out of 200 kVA is 20%.(this is from standard source). Could you give me your source of information for 25% ??

Regards,

sks

With DOL starter it should take at least 50% of rating and with auto transformer/star-delta it should take more. Although the starting current is high the powerfactor drops.

Like I said its not an exact science. There are many figures you haven't presented such as the generator impedance, the type of AVR fitted etc.

Starting a DOL motor again depends on what sort of mechanical appliance it is driving - a fan load is particularly bad.

Its an engineering judgement. Only you know the true load, type of load etc.