Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations cowski on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Power Quality Standards

Status
Not open for further replies.

Morteza2

Electrical
Apr 19, 2012
11
Dear colleagues,

I have a few questions with regards to power quality standards.

I will first outline the application I am currently working on and the reason that I'm raising these questions (background).

Background:
I'm working on a relatively large-sized VFD application; this VFD feeds a pump, and it's around 400kVA, with 480V, 60Hz supply power. We have been experiencing many shut downs on this VFD and so we installed a logging power quality monitoring device (Fluke 1750) on the input of the VFD to see what kind of supply power quality we are working with. Now, I want to know how to evaluate this power supply quality according to industry standards.

Questions:
1. Is the only available standard currently specifying power quality requirements EN 50160?

2. I realize in North America we have ANSI C84.1, but from what I understand, it doesn't quite do the job of EN 50160 since it doesn't specify requirements/limits for transients (i.e. voltage sages and swells). Is that understanding correct?

3. What is the relationship between ITIC and CBEMA curves and EN 50160? Are they both derived from EN 50160?

4. Based on their description and background, ITIC and CBEMA were developed for the highly sensitive electronics applications; are these same curves also typically used to evaluate power quality for high power electrical applications such as the one I'm working with?

5. If the answer to question #4 is no (which would make more sense), is it safe to say that there are currently no standards that specify transient limits for high power applications, and the only available standard to use as a benchmark is ANSI C84.1 (which doesn't touch transients)?

6. Any other comments/suggestions?

Thank you very much in advance.

 
Replies continue below

Recommended for you

IEEE 519 is the relevant standard in the US regarding harmonic distortion.
 
Thanks; I should have clarified, I meant besides the harmonics. In our application, the voltage harmonics levels from the utility is actually satisfactory (~1.3%); when our VFD is running voltage harmonics goe up a little but still within the required 5% for the voltage class. What I want to know more about are the standards of power quality with regards to interruptions, sags, swells, etc.
 
Morteza2
What error codes are you getting on your VFD panel after the shutdowns?
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor