ETAP Power Grid Modeling help
ETAP Power Grid Modeling help
(OP)
I am unsure how to enter this utility information (below)correctly within ETAP v6. Can someone please advise? ETAP asks for percent R and X, but I have what is shown below. Also, would I enter it as 13.2kv or 480V? Thanks
"This location is served from XXXX substation via 13.2 kV Feeder 158 and a 75 kVA bank of transformers (13.2 kV/480 volts). Based on a transformer impedance value of 2.10% and the existing high-side driving point impedance, the available 3 phase (3Ø If) fault current at this location should not exceed approximately 3,890 amps and the available Line to Ground (L-G If) should not exceed approximately 3,950 amps. Both values were calculated at the 480 volt transformer low side bushings and do not include the impedance contributions of the secondary cable.
The driving point impedances on a 100MVA base at the low side bushing are:
Z1 = 6.890 R + j 30.173 X
Z0 = 7.395 R + j 28.556 X
"This location is served from XXXX substation via 13.2 kV Feeder 158 and a 75 kVA bank of transformers (13.2 kV/480 volts). Based on a transformer impedance value of 2.10% and the existing high-side driving point impedance, the available 3 phase (3Ø If) fault current at this location should not exceed approximately 3,890 amps and the available Line to Ground (L-G If) should not exceed approximately 3,950 amps. Both values were calculated at the 480 volt transformer low side bushings and do not include the impedance contributions of the secondary cable.
The driving point impedances on a 100MVA base at the low side bushing are:
Z1 = 6.890 R + j 30.173 X
Z0 = 7.395 R + j 28.556 X






RE: ETAP Power Grid Modeling help
RE: ETAP Power Grid Modeling help
RE: ETAP Power Grid Modeling help
RE: ETAP Power Grid Modeling help
would what I have shown, Z1 = 6.890 R + j 30.173 X, be considered as %R+j%X, or do I need to convert it?
RE: ETAP Power Grid Modeling help
RE: ETAP Power Grid Modeling help
RE: ETAP Power Grid Modeling help
Another oddity of E-tap. There is a spot for entering the PU data but why ask for it in % and require the user to multiply by 100? It's been a few months so I forgot about that in my last post. If you forget, the short circuit currents are unrealistically high.