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@adi 3291, Sorry for the late reply. IEEE has a document on that but IIRC, grid-forming IBRs run around 2 to 3 pu Isc contribution. For grid-following IBRs, that is what I mentioned to be 1.2 to 1.5 pu. LINK

@adi 3291, IDK if the data you've provided changed. Having 4 megapacks connected to a 4.4 MVA inverter transformer requires you to have 300/4.4 = 75 inverter transformers, not 78. 78 inverter transformers with 4 megapacks per transformer will require 4 X 78 = 312 megapacks, not 310! Still, any...

At the battery terminals, the short circuit current is only limited by the internal resistance of the battery. At 480VDC and an internal resistance of 20 milli-ohms, you'll have 24 kA. Available short circuit currents from inverters (at the AC side) are in the range of 1.2 to 1.5 times the rated...

@unnikri57 (Electrical) Please share with us some details like voltage level, prevalent harmonics detected, size and capacity of PCC panel versus cap bank MVA. Gr8blu is correct, reactor in series with a cap will have the effect of filtering harmonics present in the POCC. Whether you need those...

Too few inputs. Please complete your generator specs. You could find better luck if others will be given ideas about voltage, winding preference, pitch, local environment, etc.

@Pandit, Correct. If the VFD panel displayed 114.5 kW, it means the power transmitted by the VFD to the motor. Subtract the VFD losses and you'll get the actual power delivered by the VFD to the motor. To consider @FacEngrPE's idea on finding the power delivered at the motor shaft, one has to...

YKC, Please see it this way: if your load amps differ in every phase, naturally the voltage drop in each of the supply line will differ. Even if the source is balanced, the resulting terminal voltage at the point of common coupling at your location will not be equal. That is what @stevenal is...

@che12345, Goggle is friend. It could be your too. Go figure. @Edelma_1, The best way to go is hire the services of a third party doing harmonics frequency sweep on your system. We did that. That neutral to phase current ratio hold true if the dominant harmonics in your system is the 3rd...

Assume that the meter is fine. Check if the PFC unit is really "working". My experience in my other life was that the PFC unit was set wrongly; the PFC unit inserted more capacitors for a certain power factor resulting to over-correction. Then, the contactors were pulling in and then dropping...

Y'all. The power draw should be the amount of power required when connecting the equipment under test plus the test lead resistance plus the load resistance. E.g. a 100A thermal overload relay with have a resistance per pole of about 0.378 milli-ohms, Using a 38 mm2 x 1 meter cable with a...

@EdeLma_1, The formula I got is In/Ip = 3 X (per unit THD)/(sqrt(1+(per unit THD)^2) for circuits laden with 3rd harmonics. In = neutral current, and Ip = phase current. I got 45% with 15% THD

OP believes it is best to test the sensor in-situ. That's the main problem. Unless he thinks out of that box, he'll never see that are many ways to do it.

@SK07, Your 3150A busbar rating @ 50 deg C rating is an overkill, IMO (if there are no future expansions being contemplated). Your expected full load is just half of that. If the install is still on the drawing board, I recommend you downgrade to 2300A (1/2" x 4") or 2750A (1/2" x 5"). The rule...

@SK07, You haven't posted the temperature at which your installation is designed for. Can you specify if it's for 30 degrees, 50 or 65 degrees C?

@KillBill7, We have the same problem in my other life. What we did was drive additional ground rods at our transmission towers. We measured earth resistance after each activity and make sure our earth resistances don't exceed 25 ohms. Also, we found out those copper conductors we used were like...

@bdn, Don't overthink it. There will always be slight differences in voltages. Just let the synchronizer do the job. You won't get synchronized if the differences are too big for the control equipment.

@che, The only way you can be sure the motor is very near it's rated speed is to do a motor acceleration time simulation. There are softwares that offer to do those. But you can calculate yourself using the well-extablished motor equations.

We did have lots of damaged contactors that were traced to wrong setup of transition timing. The worst situation was when the arc chutes themselves helped in the destruction, the chutes accumulated previous debris, the contact arc sustained when switching happened.

@cr, Please take note of the use of the word "like". That means, it is not the thing, it is just "like" in plain English.

As an example, we have a 2.6 MW ball mill that is supplied with 13.8 kV from our on-site generator. The difference I think is ours is a WRIM, not synchronous motors. The motor is also controlled using liquid resistor on starting.