010.40 This is an attempt to provide a graphical index for the most common substation installations. The numbers refer to specific section in the manual. This is not intended to cover all areas applicable to a particular installation.

170 The major changes to this table relate to the triplex core and coil construction requirements for grounded wye to wye (ungrounded or grounded) transformer configurations. The triplex core is required for all grounded wye primary connections. We have also clarified the triplex core requirement in terms of transformer size. Previous editions did not require the triplex core for “transformers larger than 2500kVA.” The new verbiage is the triplex core is not required for “transformers 3000kVA and larger.” Also, the exceptions to the triplex core requirement are explicitly outlined in 170.10.b.1 through 170.10.b.4.

180 The entire grounding section has been rewritten. The major changes are to ground grids installed in areas of high soil resistivity.

220.40.10 To the drawings we added the conductors that connect the instrument transformer cases to the neutral/ground bus.

220.40.20 Eliminated the 3 phase 3 wire metering for 15kV.

220.40.80 Combined the 26.4kV and 34.5kV installations on one drawing. Eliminated the 3 phase 3 wire metering.

260 This entire section was rewritten to clarify the requirements for security of the switchgear. Added section 260.75.10 which is directly from NEC Table 490.24.

270 Section 270 has undergone major revisions and additions. Specific language is included to outline the requirements for substations not owned by We Energies, but which contain We Energies equipment. This is primarily applicable to the downtown Milwaukee area, but may occur elsewhere on the system.