For industrial and distribution MV grids, we commonly use Resistance grounding (NGR), but what I've seen in Renewable generation projects (wind & solar) is that they're using reactance grounding (neutral point coil).
Can anyone please clarify what are the reasons/advantages of reactor grounding...
Hi All
I have a case with an underground pipeline (equipped with cathodic protection) that I need to cross with a MV cables underground trench and couldn't find some reference or litterature regarding the possible impacts of the MV lines on the cathodic protection, minimum clearance...
I have a tansformer as follows:
Voltage: 60kV / 10kV
Rated power: 45/60/75 MVA (ONAN/ONAF/ONAF)
Impedance voltage at rated power and rated voltage at 75°C: 10% +/- 7.5% tol.(at 45 MVA)
ETAP does not allow to change base MVA (it is always the biggest rating). Please how to specify on ETAP the...
Hello everyone
I need advise regarding the proposal attached, to derive the power supply to a new 11kV/415V transformer from a PFC feeder.
Are there any restrictions in the international standards (preferably IEC)? constraints in term of protection, availability...
Thank you for...
Bonjour
We have an HV Neutral directly grounded using an insulated cable and a disconnecting switch (normally close).
The question is regarding the insulation level of this grounding material (cable+switch) per IEC standards?
should it be phase voltage 60kV (72,5) or 60kV/sqrt(3) or an LV cable...
Dear all
I need your help for 2 issues :
1/ To order MV cables, please advise how to specify short circuit withstand capacity on cable metallic screen.
What I have at this stage, is the preliminary calculation of max short circuit value (for example 40kA @ 10kV level) which I use in equipement...
I have a question regarding rated impulse test voltage (BIL) selection for an MV switchgear (IEC):
-operatin voltage 10kv 50hz
-rated insulation: 17.5kv
-rated Power-Frequency Withstand voltage (1min)38kv.
Per IEC for this case, both 75kv and 95kv are possible for rated Impulse Test Voltage...
For a project in Morrocco, a solid sulphur conveyor is crossing under a HV line (63KV).
In my understanding we need 3 protections (please correct me if this is wrong):
1/ During normal operation: the HV line shall be kept out of touch (some minimum distance shall be kept between the line and...
I need details about sizing of a MV/LV transformer room and clearances according to IEC standards.
(MV = 10KV)
plz help what is applicable standard and where can I find information
Thnks.
On a MV panel, is it possible to extract one complete cabinet located at the middle without touching neighboring ones?
For makes such Merlin Gerin, Eaton...
Thanks for help
I have a configuration with 3 MV/LV transformers: 2 working and 1 standby with an auto-transfer scheme(I attached a single line diagram)
http://files.engineering.com/getfile.aspx?folder=e062394a-d37e-480e-a04a-715eb5e58a41&file=SLD1.bmp
- In normal operation, buscouplers 1 and 2 are open
-...
Can someone advise please about use of air insulated disconnecting chamber(between transformer tank and cable box), or the same oil insulated type, segregated from main tank.
What are benifits and disadvantages?
Can someone send me some details, sketches?
Thanks
BEN.
