Previous in Forum: UPS Power ELCB Tripping   Next in Forum: VSD with Star Delta Starting
Close
Close
Close
2 comments
Anonymous Poster #1

Step Load / Step kVA in DG Sets

02/16/2021 3:05 AM

What is Step Load / Step kVA in DG sets?

Reply
Interested in this discussion?
You can "subscribe" to this discussion to be notified of new comments.
Click on the Subscribe menu at the top of the page.

Comments rated to be "almost" Good Answers:

Check out these comments that don't yet have enough votes to be "official" good answers and, if you agree with them, rate them!
Guru

Join Date: Mar 2007
Location: at the beach in Florida
Posts: 29823
Good Answers: 1665
#1

Re: Step Load / Step kVA in DG Sets

02/16/2021 6:53 AM

This refers to how sensitive your equipment is to voltage/frequency dip on start-up...In choosing a generator it's important to take into account the starting requirements of the types of loads you will be supplying...

"Maximum Allowable Step Voltage Dip...

Since a generator set is a limited power source, voltage and frequency excursions will occur during transient loading events. The key is to select a generator set size that will limit these excursions to an acceptable level for proper load performance. As the maximum allowable starting voltage dip is reduced, the size of the recommended generator set increases.

If the maximum allowable starting voltage dip is less than 15%, the recommended generator set may be very large for the connected load. Some loads are more sensitive to voltage dip than others.

It is recommended to choose the most sensitive load in your project to establish the maximum allowable voltage dip while the loads are starting.

Note that for the majority of loads, maximum allowable voltage dip defaults at 35%. For North America, the maximum allowable peak voltage dip for fire pump loads defaults at a fixed 15%, and for medical imaging loads it defaults at a fixed 10%.

See also Loads Overview.

Maximum Allowable Step Frequency Dip

Since a generator set is a limited power source, voltage and frequency excursions will occur during transient loading events. The key is to select a generator set size that will limit these excursions to an acceptable level for proper load performance. As the maximum allowable frequency dip is reduced, the size of the recommended generator set increases. If assigning an overall maximum allowable frequency dip for the project in the project parameters, choose the load most sensitive to frequency dips to set the maximum allowable frequency dip.

https://powersuite.cummins.com/PS5/PS5Content/HTML/common/Binary_Asset/docs/PowerSuite5.pdf

__________________
Break a sweat everyday doing something you enjoy
Reply Score 1 for Good Answer
Guru
United Kingdom - Member - Indeterminate Engineering Fields - Control Engineering - New Member

Join Date: Jan 2007
Location: In the bothy, 7 chains down the line from Dodman's Lane level crossing, in the nation formerly known as Great Britain. Kettle's on.
Posts: 29931
Good Answers: 808
#2

Re: Step Load / Step kVA in DG Sets

02/16/2021 3:49 PM

Matthew 7, 7.

__________________
"Did you get my e-mail?" - "The biggest problem in communication is the illusion that it has taken place" - George Bernard Shaw, 1856
Reply
Reply to Forum Thread 2 comments
Interested in this discussion?
You can "subscribe" to this discussion to be notified of new comments.
Click on the Subscribe menu at the top of the page.

Comments rated to be "almost" Good Answers:

Check out these comments that don't yet have enough votes to be "official" good answers and, if you agree with them, rate them!

Previous in Forum: UPS Power ELCB Tripping   Next in Forum: VSD with Star Delta Starting

Advertisement