×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

EN 50522 earthing of power instalations exceeding 1 kV AC - calculation of actual touch voltage

EN 50522 earthing of power instalations exceeding 1 kV AC - calculation of actual touch voltage

EN 50522 earthing of power instalations exceeding 1 kV AC - calculation of actual touch voltage

(OP)
Hello,
The European standard EN 50522 is describing with full details how to evaluate the touch voltage.
Item 5.4.2 is depicting a design process which is summarized in a flow chart in Figure 5 in the standard.
In my case:
The criteria of earth potential rise (Ue) < double the allowed touch voltage is not met.
The design flow chart in leading me to take “recognized specified measures M” which are also detailed in the standard – in Annex E of the standard.
Table E.1 of the standard is attached.
My position in the table is the last bottom row (tf<5s & UE> 4 x Utp) and according to the standard I need to “Proof UT < Utp.
The problem I have is that I cannot find in the standard how to calculate UT, which is the actual prospective touch voltage.

Does anyone know where this calculation is described in EN standards (or IEC)?

RE: EN 50522 earthing of power instalations exceeding 1 kV AC - calculation of actual touch voltage

See[for instance]:
file:///C:/Users/user/Downloads/pub16573.pdf
fig 1 page 80

RE: EN 50522 earthing of power instalations exceeding 1 kV AC - calculation of actual touch voltage

Whatever that file is, it is located on your C:/ drive. smile

RE: EN 50522 earthing of power instalations exceeding 1 kV AC - calculation of actual touch voltage

It is very funny, indeed. However it is not my C: but of:
Ilze Priedite-Razgale1, Janis Rozenkrons2, 1-2 Riga Technical University
and if you’ll put it in Google-for instance-you’ll get the pdf.

RE: EN 50522 earthing of power instalations exceeding 1 kV AC - calculation of actual touch voltage

I'm not sure what term you are Googling but I can't find it other than some Russian-language site which I'm not clicking. Can you post a working link?

RE: EN 50522 earthing of power instalations exceeding 1 kV AC - calculation of actual touch voltage

I am sorry.Try this one
file:///C:/Users/user/Downloads/pub16573%20(4).pdf
or
https://www.google.co.il/search?q=Development+of+a...
The title has to be as follows:
Development of an Algorithm and Software “MVES-TV 2012” for Touch Voltage Evaluation in MV Networks

RE: EN 50522 earthing of power instalations exceeding 1 kV AC - calculation of actual touch voltage

(OP)
Thanks for the information.
however, the figure 1 in page 80 in your mentioned file is providing the ALLOWED TOLERABLE touch voltage.
I was asking about the calculation of the actual developed tough voltage which needs to be lower than the value from figure 1.
moreover, this figure 1 is included in IEC 50522 itself.

so the mystery is still unsolved here.

RE: EN 50522 earthing of power instalations exceeding 1 kV AC - calculation of actual touch voltage

In the above article it is written:
"If Ue>4*Utp ,then UT<=Utp is proved according to EN 50522:2010. [7], [8]"
In the list of references :
[7] Post Glover “Neutral Grounding Resistors. Technical information”
[8] Guide for Safety in AC Substation Grounding, IEEE Standard 80:2000
That means, in my opinion, UT has to be calculated according to IEEE 80/2000.
In my opinion also, nor BS7430 neither DIN-VDE 0141 presents any reference to touch and step voltage.

RE: EN 50522 earthing of power instalations exceeding 1 kV AC - calculation of actual touch voltage

(OP)
OK! now we are starting to get close.
however, the reference from IEC set of standards into IEEE is strange.
i do know the IEEE 80.
however, i am straggling to figure out the IEC methodology to handle the tough voltage, and there are gaps in the system, as far as can understand.
i really hope to find a solution within the IEC system.
maybe my effort is for nothing. I hope not.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources