Recent content by LDKGR

Hi Power0020, if you want to be on the safe side no more than 10%, aux no more than 3%. Moreover, check the motor's torque curve and the load curve.

Rule of thumb : Design your ventilation system for a ΔT=5K plus 20% air flow safety factor.

Hi ScottyUK, thanks for your answer. Consequently which is your proposal for my simple case ?

Hi electrichie123, there is no changeover supplies. Step-up transformer is fed by a standby gen-set. YNd configuration means STAR connection in medium voltage 20kV side (I'll use solidly grounded neutral) and DELTA connection in low voltage 0.4kV side.

Hi tem1234, the only way I know is to recheck the cable according to its production standards.

Thanks jghrist for your answer. Perhaps the question was not so clear. So, is there any regulation (or other tech restriction) which determine to use an exact vector group for the step-up trafo if the vector group of the step-down trafo (Dyn11) is known ?

Hi everyone, I am trying to finalize the specification of a step-up transformer but I can't find a lot of information about vector group. The existing step-down transformers of the installation are Dyn11 type. After a discussion with a transformer manufacturer his proposal was YNd11. A rough...

This type of installation is essential in case of non-linear loads (VSD) supply cables (depends of EMC level you want to achieve in your installation, cable tray metal cover etc). Moreover as a designer you can calculate with higher accuracy the total resistance of ground path. Of course, as...

Hi masalah, mechanical connection of two parts sometimes is not an adequate electrical connection. So it's better not to mix them up.

FluidFlow3 is cheaper.

I agree with jraef. In Greece there were many fights with puplic power corporation for the same reason. Nobody wants a transmission line near his house. Now there is a rule of thumb "Don't buy a house if there is a transmission line in a distance of 50m".

Hi isnata, use polyester in two layers reinforced with fiberglass. Two layers in cross will give you extra safety. Keep in mind that the preparation of the surface of the metal plate is very important for a good result.

Hi LionelHutz, sysy is student

Hi sysy, my recommendation is to start with a very basic diagram (Grid - MV switch - Trafo - LV switch - Load). After that you can add more and more items in your diagram according to your background.

Hi isloh, did you check the cable size according to short circuit withstand ?