ML20217N944

Proposed Tech Specs Replacing Two low-range Pressurizer Pressure transmitters,PT-103 & PT-103-1,which Will Identify That Two low-range Pressurizer Pressure Instrument Channels Are Independent & Redundant Only

ML20217N944
Person / Time
Site:	Millstone
Issue date:	04/29/1998
From:	NORTHEAST NUCLEAR ENERGY CO.
To:
Shared Package
ML20217N942	List: B17112, Application for Amend to License DPR-65,replacing Two low- Range Pressurizer transmitters,PT-103 & PT-103-1 Which Will Identify That Two low-range Pressurizer Pressure Instrument Channels Are Independent & Redundant Only ML20217N944
References
NUDOCS 9805060005
Download: ML20217N944 (4)

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! Docket No. 50-336

! B17112 I

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l Attachment 3 l Millstone Nuclear Power Station, Unit No. 2 License Amendment Request - Unreviewed Safety Question l Proposed Revision to Final Safety Analysis Report i Pressurizer Pressure - Shutdown Cooling System Interlock t

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April 1998 90050g0 PDR y [ M ppR 336 P

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.; , MNPS-2 FSAR the event of a high level error signal concurrent with a high-pressure condition. These two channels are also used to provide pressurizer pressure signals tc the RRS. The two channels are continuously recorded in the main control room and are provided with high-and low pressure alarms.

4.3.8.2.3 Pressurizer Pressure D

Two low-range pressure measurement channels provide a control room indication of RCS pressure during plant startup and shutdown in the main control roorn. They also provide independent pressure signals to the shutdown cooling suction isolation valves (refer to Section 9.3.4.1) which prevent these valves from opening above a selected set point. If ,

the shutdown cooling suction valves are open when the pressure exceeds a selected set point (280 psia), an annunciator receives a signal to alarm from these pressure channels.

The channels also provide signals to actuate the PORVs for LTOP. These two instrument channels are independent redundant ;nd dF;;;;; in thc; th :::nsh ;::: p::h:::d

'::= dll!:::::';;nd;;;. and 4.3.8.2.4 Quench Tank Pressure This measurement channel provides a quench tank pressure indication in the main control room and actuates a high-pressure alarm. High quench tank pressure indicates that the tank has received a discharge from the safety or relief valves. The operator will then take action to restore the tank to normal operating conditions.

4.3.8.3 Level

( 4.3.8.3.1 Pressurizer Level e

Two pressurizer level channels are used to provide two independent level signals for control of the pressurizer liqi id level. These signals are used to deenergize the pressurizer heaters on low low pressurizei level to prevent heater burn out, provide input to one pen in each of the two two-pen recorders in the control room, and actuate high- and low-pressure pressurizer level alarms in the main control room. The second pen on each level recorder records the programmed pressurizer level computed by the RRS as a function of the average reactor coolant temperature. The level transmitters are compensated for the steam and water densities existing in the pressurizer during normal operation.

The liquid level in the pressurizer is programmed to vary as a function of average reactor coolant temperature. This level set point is computed by the RRS and furnished to controls associated with these measurement channels. One of the two measurement channels is manually selected to furnish an actual liquid level signal to the controls if these two signals differ, the level control adjusts the CVCS charging or let-down flow rates to make the difference zero. Each of the level channels is indicated in the main control room and is equipped with a high and low level alarm in the control room.

4.3.8.3.2 Pressurizer Level One wide-range pressurizer channel is provided for main control room indication of pressurizer level during plant startup and shutdown.

4ss.wa 4.3-24 Ma/1994 l

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l Docket No. 50-336 B17112 l

l Attachment 4 I

( Millstone Nuclear Power Station, Unit No. 2 License Amendment Request - Unreviewed Safety Question l Proposed Revision to Final Safety Analysis Report l Pressurizer Pressure - Shutdown Cooling System Interlock List of Regulatory Commitments

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April 1998 l

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U.S. Nucl::r R:gul: tory Commission B17112/ Attachment 4/Page 1 l

List of flegulatory Commitments The following table identifies those actions committed to by NNECO in this document.

Any other actions discussed in the submittal represent intended or planned actions by NNECO. They are described to the NRC for the NRC's information and are not regulatory commitments. The Manager - Regulatory Compliance, Millstone Unit No. 2, should be notified of any questions regarding this document or any associated regulatory commitments.

REGULATORY COMMITMENT COMMITTED DATE OR OUTAGE None N/A l

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