- General Support
- Oneline & User Interface
- License Key Issues
- Downloading/Installing Software
- Printing
- Reports
- Equipment Modeling
- DAPPER (Demand Load)
- DAPPER (Load Flow)
- DAPPER (Short Circuit)
- CAPTOR (TCC)
- Arc Flash Evaluation
- Equipment Evaluation
- Cable Ampacity
- A_Fault (ANSI)
- IEC 60909 Fault
- IEC 61363 Fault
- TMS (Transient Motor Starting)
- HI_WAVE (Harmonics)
- Unbalanced/Single Phase
- DC Systems Analysis
- GroundMat
- Cable-3D
- Scenario Manager
- Backup & Import/Export
SLG Current Calculations
Description
When PTW calculates the SLG current in bus SWBD, the following equations are used for these 2 cases:
Case1 (utility is in transformer primary side)
Isc1 = V0/(Z1+Z2+Z0)
Z1 = Zcable1 + Ztranformer1 + Zutility1
Z2 = Zcable2 + Ztranformer2 + Zutility2
Z0 = Zcable0 + Ztranformer0
Case2 (utility is in transformer secondary side)
Isc2 = V0/(Z1+Z2+Z0)
Z1 = Zcable1 + Zutility1
Z2 = Zcable2 + Zutility2
Z0 = Zcable0 + (Zutility0 || Ztranformer0)
Isc1 and Isc2 are totally different.

When PTW calculates the SLG current in bus SWBD, the following equations are used for these 2 cases:
Case1 (utility is in transformer primary side)
Isc1 = V0/(Z1+Z2+Z0)
Z1 = Zcable1 + Ztranformer1 + Zutility1
Z2 = Zcable2 + Ztranformer2 + Zutility2
Z0 = Zcable0 + Ztranformer0
Case2 (utility is in transformer secondary side)
Isc2 = V0/(Z1+Z2+Z0)
Z1 = Zcable1 + Zutility1
Z2 = Zcable2 + Zutility2
Z0 = Zcable0 + (Zutility0 || Ztranformer0)
Isc1 and Isc2 are totally different.