1. Confidential - For Internal Use Only
Gen Drop Addition
Mount Signal Solar (DREW GEN 4)
A new 250 MW Solar (DREW GEN 4) facility will be interconnected via a shared 230kV line at DREW (DW) Substation
Through logic additions in the SEL-2411 RAS relays at existing DREW GEN 2, Gen Drop at Mount Signal Solar (DW GEN 4) will be added to the following RAS:
TL50001 – Instantaneous trip (Enabled during N-1 operation) – WAPS
TL50003 – Instantaneous trip (Enabled during N-1 operation) – WAPS
TL50004 – Instantaneous trip (Enabled during N-1 operation) – WAPS
TL50005 – Instantaneous trip (Enabled during N-1 operation) – WAPS
TL23040 IV 500kV N-1 – Instantaneous trip (Normally enabled) – WAPS
Imperial Valley Bank 80 – Sequential trip (Enabled during N-1 operation) – LAPS
Miguel Bank 80/81 – Sequential trip (Enabled during N-1 operation) – LAPS
Confidential - For Internal Use Only

2. DREW GEN 4 is connected via TL23067 to the 230kV Bus at DREW
Gen Drop Addition
Mount Signal Solar (DREW GEN 4)
OCO GEN
OCOTILLO
TL50003
DREW GEN 4 is connected via TL23067 to the 230kV Bus at DREW
SUNCREST
SYCAMORE
CANYON
TL50005
TL50004
TL50001
TL50002 NG
MIGUEL
DW GEN 1
ECO BK 83 IV BK 81 BK 80 BK 81 BK 82
TL23067 BK 62
DREW 230KV
ECO GEN 1
IVS
IV 230kV Bus
OTAY MESA
DW GEN 2
DW GEN 4
ECO GEN 2
BUE
IV PST TJ
ROA
TDM
CLR2
IV GEN 3 DU
DW GEN 3
Confidential - For Internal Use Only

3. Confidential - For Internal Use Only
Gen Drop Addition
Mount Signal Solar (DREW GEN 4)
Existing RAS can trip the following generation:
1200 MW combined cycle (CLR2, TDM)
720 MW solar (DW1, DW2, DW3, IV GEN 3, DU)
550 MW wind (OCO, BUE1, ECO GEN)
Total of 2470 MW
DW GEN 4 will add 250 MW gen drop capability
Confidential - For Internal Use Only

4. Confidential - For Internal Use Only
Gen Drop Addition
Mount Signal Solar (DREW GEN 4)
DREW GEN 4 Substation
(2) 230/34.5kV transformers
(5) 34.5kV feeders
Sequential trip operates lockout relay on 3-second delay
All other RAS trips are instantaneous
Confidential - For Internal Use Only

5. Confidential - For Internal Use Only
Gen Drop Addition
Mount Signal Solar (DREW GEN 4)
Confidential - For Internal Use Only

6. Confidential - For Internal Use Only
Gen Drop Addition
Mount Signal Solar (DREW GEN 4)
Confidential - For Internal Use Only

7. Confidential - For Internal Use Only
Questions?
Confidential - For Internal Use Only