Help Needed in Selection of Generators

You want somebody to help you justify a bad decision that you made?

Will your former customer take the word of anonymous strangers you have solicited on an internet forum that your poor decision is somehow justified?

Gee, Mr. Customer, you gotta let him use the generators he has already purchased, cause he's already purchased them.

Good luck.

Let me add some information for you

Ask him the reason for 70%, dont let him to speak from his stomach without any calculation or proof.

Do your calculation exactly with consideration of kVA, power factor, Kw, derating factors for altitude, and draw for him generator capabilty curve and convince him base on your calculation.

Thanks brother..... i cant understand why the others are trying to spray oil in to the fire......let me try to prove it as you mentioned ... but still cant understand this 70% stuff

I haven't even attempted to determine whether you need a different generator or not, but I hope you've made some contact with the generator supplier and started to investigate the possibilities of canceling the order or returning the generators (are they already delivered, are they a custom unit, etc., etc., etc.?)

If the generator supplier is reputable, I would expect that they have some policy (or even policy or not), would want to try to help their customer (you) to be satisfied.

What is "ios" and what regulation specifies 70%?

Is the 725 kva the continuous rating for the gensets? (Just checking; if the standby rating is 800, 725 continuous makes sense.)

absolutely right tornado...... 800 is standby rating and 725 is continues..... dont know who the hell is this ios

You have already added a 20% "safety factor" above the 371kw diversified load. The 70% utilization figure is like adding 30/70 ≈ 43% more safety factor. Seems like overkill. Does the "ios" regulation contemplate that you already had the 20%?

Looking at it another way, 463.4kw ÷ 0.85pf ≈ 545kva; and 545/725 ≈ 0.75. This does exceed the 70% figure, but I think I've seen allowable utilizations of 80%. Your selection looks rational, even if it doesn't satisfy a particular rule.

If you present your case in this way, perhaps you can get a waiver. The absence of large motors suggests that you would seldom, if ever, get into a bona fide problem. Moreover, running near 80% capacity will be more fuel efficient than running near 70% capacity. If I were the buyer rather than the bureaucrat, I would go for this.

Thank you so much brother. Its good info for me. Let me add this too.