ML17252A855
| ML17252A855 | |
| Person / Time | |
|---|---|
| Site: | Dresden, Indian Point  |
| Issue date: | 01/25/1974 |
| From: | Cobean W Consolidated Edison Co of New York |
| To: | O'Leary J US Atomic Energy Commission (AEC) |
| References | |
| Download: ML17252A855 (2) | |
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1~t Cl\\~ ED JAN28l974~ l
- 'Regulatory Docf{et File
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- Ii s. mm~ El\\E.Rli1 t!Ji.il.1\\SSIOll Consolidated Edison Company of New York, Inc.
4 Irving Place, New York, NY 10003 Re:
Mr. J<;>hn F. '0' Leary, Director.
Directorate of Licensing Off ice of Regulations U.S. Atomic Energy Commission Washington, D. C.
20545
Dear Mr. O'Leary:
January 25, 1974 Indian Point Unit No. 2 Facility Operating License DPR-26, A.0.-4 CV 50-247
'C7-The following report is provided pursuant to the requirements of Section 6.12.2(a) of the Technical Specifications to Facility Operating License No. DPR-26.
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- iL!ail sect\\1111 Periodic surveillance test PT-M2, "Reactor Coolant Temperature Analog Channel Functional Test -.6T Overtemperature and~T Over-power", was performed with. Unit No. 2 in the cold shutdown con~
di tion. _.-The limiting safety system settings of Channels I and III of the Qverpower.OT Reactor Trip circuitry were found to be below that required by Technical Specification 2.3.l.B95).
Chan-nels I and III have since been recalibrated and tested satisfac-torily..
'These particular devices are part of a four channel reactor trip logic where activation of any two of the four bistables (one p~r channel) will produce a reactor trip signal.
Since the Channel II and IV bistables were found to be operating correctly, over-power~ T would have caused a reactor trip to occur within the range prescribed by the Technical Specifications.
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As stated in our January 18, 1974 letter to you, Nuclear Power Generation Department is investigating the setpoint drift problem in conjunction with the manufacturer and our Engineering Depart-ment.* If our investigation substantiates that a particular bi-stable component is the cause of the setpoint drifts experienced, we plan to replace these components on an appropriate progress*ive schedule with priority given to those components in the reactor protection circuitry.
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Because the logic circuitry was still operating, s.a~ety irnplica~
tions to the occurrence were not cons:idered significant~
However~
the investigation into the re~son~ for recently reported setpoint drift will continue ~ith th~ *interit of reducing the likelihood of their incidence~
cc:
Mr. James: P. O '*Reilly Very* truly* yours*~
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[2_ ~~1 Warren R.. Cobe*an ~
- J:r:::...,. Mana,ger Nuclear Power Genera,ti'on
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