Hello Folks,
my customer is building plant and entire electrical area classification is per API 505 rev 2013 (with all later additions/ammendments) methodology.
Now one of big packages comes made per IEC 60079. As far as i know, there are small differences despite desire for harmonization of...
Hi Guys,
we had long discuss with Vendor, and apparently they treat motor terminal box similar to the MV SWGR, specifically IEC 62217-200 and AFLR internal arc classification.
If you read al 4 criterions, after the arc test, external structure and enclosure is allowed to be deformed, while...
indeed, arc during fault will heat all up, plasma created might be very hot, pressure increases and rupture discs opens to prevent explosion, i think.
But still - whether API requires to survive all internals, or not?
Or we need to agree that all will be wasted, inclusive terminal box?
qqitek
Dear Folks,
I got confused by API 546 cl. 3.1.2 requirement on motor terminal box (MTB) with rupture discs, which states:
"The terminal box for the main power lead terminations shall be capable of withstanding the pressure build-up
resulting from a three phase fault of the specified MVA...
Thank you 7another4
For the moment I do not have access to NEMA WC51.
But can you confirm that this standard determines the multilayer cable filling (high filling of tray) or randomly circuit?
This makes difference.
Random issue is important, but now I have trouble with high filled trays, and...
Hello Folks!
I have question regarding IEC 60364-5-52 regarding approved methodes of cable routing via ladders/trays and derating factors.
Q1) Table B.52.17 item 1.
Can we use the worst reduction factor (0,38) for multilayer cable routing? It is very often that cables are laid on several layers...
thread248-100920
Hi Mates!
I would like to know your opinion on lightning protection on areas where zone 1 and 2 are classified.
I met design that all parts of LPS are outside hazardous zones.
It is reasonable.
However the att D5.1 of IEC 62395-3 says that 1m separation is needed, but if it is...
Hello Folks,
In one of our project for power plant there is customer requirment stating:
"Cables shall be rated IPX7 water-resistant (temporary submerged IEC 60529)".
It is strange requirement, because IEC60529 is about enclosures, not cables.
I made review among cables vendors and it occured...
Dear Warros, can you state the code, where demand factors are determined?
I am from IEC world, so do not know any standard describing demanding factors. It usually comes from designer experience and estimations.
I will appreciate if you point out some codes for reference.
thanks
qqitek
Hi GadreP,
generally, the main objective that shall be concidered is fire security requirements. I guess that trafo is oil filled, right?
You must determine oil containment volume (oil m3 -from vendor), distances from nearest objects (fire separation), clearances on HV/LV side (voltage...
Thanks Folks,
I've noticed in one of the book from ANSI world, that hinged side is always connected to the nearest circuit breaker side, while jaw end to the OHL side.
However in IEC world I couldn't found any guidance.
magoo2 - probably you are right
davidbeach - i would disagree.
Have a...
Hi Fellows,
I have question regarding 132kV vertical break disconnecting switch.
Is there any rule (IEC, ANSI, NEC, BS whatever) determining orientation of disconnector in relation to the incoming supply?
That means - jaw end shall be connected towards the incoming supply, while travelling...
