ML20126C587
| ML20126C587 | |
| Person / Time | |
|---|---|
| Site: | FitzPatrick  |
| Issue date: | 06/05/1985 |
| From: | NRC |
| To: | |
| Shared Package | |
| ML20126C590 | List: |
| References | |
| NUDOCS 8506140469 | |
| Download: ML20126C587 (1) | |
Text
r JAFNPP 3.1 BASES (cont'd) subchannel.
APRM's B, D and P are contamination.
Discharge of excessive arranged similarly in the other amounts of radioactivity to the site protection trip system.
Each protection environs is prevented by the air ejector trip system has one more APRM than is offgas monitors which cause an isolation necessary to meet the minimum number of the main condenser offgas line.
required per channel.
This allows the During the Hydrogen Addition Test, the bypassing of one APRM per protection normal background Main Steam Line trip system for maintenance, testing or Radiation Level is expected to increase calibration.
Additional IRM channels by a factor-of approximately 5 at the have also been provided to allow for maximum hydrogen addition rate as i
bypassing of one such channel.
The indicated in note 16 Table 3.1-1.
The bases for the scram setting for the IRM, scram setpoint will be reset to three APRM, high reactor pressure, reactor low times the projected background radiation water level, main steam isolation valve level prior to performance of the test.
(MSIV) closure, and generator load re-The setpoint will be restored to normal jection, turbine stop valve closure are following completion of the hydrogen discussed in Sections 2.1 and 2.2.
addition test.
Instrumentation for the drywell is A Reactor Mode Switch is provided which provided to detect a loss of coolant actuates or bypasses the various scram accident and initiate the core standby functions appropriate to the particular cooling equipment.
A high drywell plant operating status.
Reference pressure scram is provided at the paragraph 7.2.3.7 FSAR.
same setting as the Core and Con-tainment Cooling Systems (ECCS)
The manual scram function is active in initiation to minimize the energy which all modes, thus providing for a manual must be accommodated during a loss-of-means of rapidly inserting control rods coolant accident and to prevent return during all modes of reactor operation.
to criticality.
This instrumentation is a backup to the reactor vessel water The APRM (high flux in startup or level instrumentation.
refuel) System provides protection against excessive power levels and short High radiation levels in the main steam reactor periods in the startup and line tunnel, above normal levels due intermediate power ranges.
to the nitrogen and oxygen radioactivity, are an indication of leaking fuel.
A scram The IRM System provides protection is initiated whenever such radiation level against short reactor periods in these exceeds three times normal background.
The ranges.
purpose of this scram is to reduce the source of such radiation to the extent The Control Rod Drive Scram System is necessary to prevent excessive turbine designed so that all of the water which 8506140469 B50605 Amendment No. 34I, 1)Af, 90 PDR ADOCM 05000333 l
P PDR
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