IOP-4: Power Operations

Purpose: To provide the instructions necessary to vary plant load from 20-100% power, determine the rate of power ascension, and establish steady state operation.

Operational Mode: Mode 1 is defined as K_eff³0.99, thermal power >5% and T_AVG³350°F.

When > P-2 {PT-505 > 15%, 1oo1, enables auto rod withdrawal}, auto rod control should be maintained except for adjustments to AFD, load changes, or IAW approved procedures.

• Compare NI power to DT for detection of miscalibration of the NIs.
• With Feedwater Crossflow valid correction factor:
  Average power level over a 1 hour period should not exceed 100% (3459 MW_t)
• Without Feedwater Crossflow valid correction factor:
  Average power level over a 1 hour period should not exceed 98.6% (3411 MW_t)
• Another CP bed must be put in service every 20%.
• If Thermal Power change exceeds 15% of RTP within 1 hr period, then inform chemistry to obtain RCS samples between 2-6 hrs.  (R16 and R41 readings required.)
• Operation without Crossflow (or with an invalid CF) shall not exceed 24 hours; if unavailable > 20 hours, restore with a valid CF within 4 hrs, or lower power < 98.6% within that 4 hours.

To prevent adjusting power into an overpower condition, the following rules are to be adhered to:

·   The NCO willensure PT505, PT506, and Average ΔT Power do NOT exceed the values specified in S2.RE‑RA.ZZ‑0011, Tables (these parameters are NOT affected by feedwater nozzle fouling).  A +0.3°F tolerance for ΔT and +3.5 psia tolerance for PT505/PT506 is allowed, which corresponds to 0.5% power.

·   The CRS is aware that the following are known to cause defouling of the feedwater nozzles.

·                  Notification from Chemistry of Feedwater/Condensate chemistry transients including ph, oxygen, iron, and chemical treatment.

·                  Reactor power change of >5% from full power.

TS 3.4.9: RCS specific activity is limited to £1.0mCi/gm and £100/E mCi/gm.  An isotopic analysis for Iodine including I-131, I-133, & I-135 2-6 hours following a power change exceeding 15% in one hour.
Basis: Limits ensure that the 2 hour dose at the site boundary will not exceed a small fraction of the Part100 limits.  The 2-6 hour requirement is based on the detection and collection of data concerning Iodine spiking.

TS 3.3.1.1: Calorimetric required at least once per 24 hrs when >15% RTP.  At least one calorimetric must be performed between 50-90% RTP.
Basis: Ensure PRNI accurate within 2% at 100% RTP.

TS 3.1.1.4: Maintain temperature greater than minimum temperature for criticality (≥541°F).
Bases: This limitation ensures: (1) MTC is within analyzed range, (2) protective instrumentation within normal operating range, (3) the P-12 {T_ave < 543°F, 2oo4, Allows manual block of HI Steam Flow SI, Enables Group I Steam Dumps} interlock above allowable setpoint, (4) PZR is capable of being operable with a steam bubble, and (5) pressure vessel above minimum RT_NDT temperature.

Power ascension limits: Limits are imposed to prevent the adverse effects of pellet – clad interaction (PCI).  This is of great concern following refueling since handling of the fuel could cause some pellet misalignment and possible clad contact.

• Control rod motion should be minimized during the post-refueling startup.  When >50% power the withdrawal rate is limited to 3 %/hour for heights at which the rods have not been previously positioned (post-refueling).

Start with:

• Group busses transferred
• 2 CN pumps in service, 1 SGFP in service

Equipment Operation During Ascension:

• >20% turbine load -                   place BSCDT pumps in service
• 25-30% reactor power -             shut MS7s
• Prior to 40% -                           evaluate MSR auto operation
• >40% reactor power -                place second SGFP in service

·        ³40% turbine load -                   ensure A-36: AMSAC BYPASSED alarm clear, begin heater drain pump cleanup

• prior to exceeding 50% -           perform AFD & QPTR calculations
• >50% -                                      place HDPs in service
• ³70% -                                      verify SGFP runback armed
• ³75% -                                      start third condensate pump
• < 89.5% -                                  ensure PT.TRB-0003 performed
• < 90% -                                     reevaluate MSRs, Calorimetric if not yet performed
• 98 - 98.6% -                              verify Feedwater Crossflow System

• Rapid load reductions, ≥5%/min, require use of AB.LOAD-0001
• Transfer Group Busses
• Stabilize <20% Rx power and go to IOP-5

Constant Load Operation:

• Set EHC setter to 66% and
• VLV POS CNTRL ramp rate to 15%/minute
• TURB INLET PRESS CNTRL ramp rate to 15%/minute

Allows operation above 98.6% 3411MWt

3hrs 20 mins to of data collection > 85% for valid Correction Factor before assending to 3411

Fuel Conditioning / Ramp Rates (NF-AP-440)

Not fully Conditioned:

0-40% - no limits

40-72% - 3% per hour

               72-100% - .5% per hour

Fully Conditioned: operated at that power level or higher for a total of 72 hours within a 7-day period

0-40% - no limits

40-72% - 3% per hour

72-90% - 2% per hour

90-100% - 1% per hour