Term
Sta Coo
Describe the functions of stator cooling. |
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Definition
-Circulate low conductivity water through the stator windings.
-Provide cooling water to the exciter rectifier banks. |
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Term
Sta Coo
Describe the limit for stator current with no stator cooling. |
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Definition
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Term
Sta Coo
Describe the stator cooling heat exchangers. |
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Definition
-HXs aligned in series.
-Shell side has stator cooling.
-Service water through tubes. |
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Term
Sta Coo
Describe system temp control. |
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Definition
-Temperature control valve that regulates by bypassing the heat exchanger.
-Maintains 40-46C.
-Normally set at 43C. |
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Term
Sta Coo
Describe the rectifier filter d/p. |
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Definition
-Filters must be replaced at next shutdown if dP reaches 8psid.
-Or every 24 months. |
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Term
Sta Coo
Describe the max flow and replacement criteria for the deionizer. |
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Definition
-Max of 50gpm (norm 45) to prevent channeling.
-Replace after 24 months ops.
-Or 1st scheduled S/D if dP reaches 15psid.
-Or conductivity > 0.5umho. |
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Term
Sta Coo
Describe the dual strainer max dP. |
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Definition
| -Swap the strainer at 8psid. |
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Term
Sta Coo
Describe the storage tank levels and alarms. |
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Definition
-Normal level is 1/2 ful.
-High or low level if 4" from normal in either direction. |
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Term
Sta Coo
Describe the temperature runback/alarm. |
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Definition
-Turbine runback at 86C.
-Alarm at 81C. |
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Term
Sta Coo
Describe when turbine runback circuitry is enabled. |
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Definition
| If stator amps are > 4000amps. |
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Term
Sta Coo
Describe the runback signals. |
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Definition
-Low generator inlet pressure: 38.6psig (236gpm).
-High generator outlet temperature: 86C. |
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Term
Sta Coo
Describe the runback time delays and stops. |
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Definition
-Lowers speed at 2%/min.
-Gen current not less than 12,000 amps in 2 min then turbine trip.
-Gen current not less than 4,000 amps in 3.5 min then turbine trip.
-Stops if initiation signal clears.
-Stops if stator current < 4000 amps. |
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Term
Sta Coo
Describe stator cooling pressure control. |
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Definition
-Control valve that keeps stator cooling pressure at least 3# less than generator H2 pressure.
-Has stops at 385 and 315 gpm. |
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Term
Sta Coo
Describe the stator cooling pump standby features and power supply. |
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Definition
-10# less than normal standby starts.
-20# less than normal reserve pump starts.
-MCC-121/131. |
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Term
Sta Coo
Describe the rectifier path flow alarms. |
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Definition
-Normal flow is 20gpm.
-Low flow at 17gpm. |
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