ML20245J487
| ML20245J487 | |
| Person / Time | |
|---|---|
| Site: | 05000273 |
| Issue date: | 04/17/1989 |
| From: | SWITZERLAND |
| To: | Grimes B NRC |
| References | |
| NUDOCS 8905040142 | |
| Download: ML20245J487 (2) | |
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,. ^ Nordostschweizerische Kraftwerke AG
'Kernkraftwerk Beznau g
CH-5312 D6ttingen Telefon 056/99 7111 Jahre Strom Telex 827429 kkb ch, Telef1x 056/99 7701 fur Mensch und Umwelt
- United States NUC1. EAR REGULATORY COMMISSION Washington D.C. 20555 USA Attn: Mr. Brian K. Grimes 1/Zeichen I/Nachricht vom U/Zeichen CH-5312 D6ttingen (Schweiz)
March 16, 1989 KBE 063 Nf/ stb April 17, 1989
Dear Mr. Grimes,
Thank you for your letter of March 16, 1939 concerning our method to trip the reactor. Your interpretation of the reactor trip devices at the Beznau power plant needs a minor correction.
The following description represents the basic design to switch off the power k to the control rod drive mechanisms CRDMs: ,"
- 1. Automatic actuation of the Reactor Trip Breakers RTBs by the Reactor [
Protection System RPS. The RPS de-energizes the undervoltage trip at-tachment of the RTBs (W, DB-25).
- 2. Manual actuation of the RTBs by the operator in the control room. This trip path energizes the trip coil of the RTBs.
1 In addition to this design we implemented two devices:
- 3. Automatic actuation of the RTBs by the RPS, energizing the trip coil.
- 4. Manual actuation (switch off) of the Generator Breaker of the motor-generator set, which generates the power to the CRDMs, by the operator in the control room. This means a redundant trip path to the basic arrange-ment.
- c -n .
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~ . Nordostschweizerische Kraftwerke AG QG@g
, Kernkraftwerk Beznau Emptinger: United States NRC. Washinaton Datum 04-17-89 Blatt 2 I
L We have no objection if you reference our method to trip the reactor in pub-licly available documents.
Enclosed you will find the wiring diagrams you asked for.
We hope this will be of service to you.
Sincerely, Nordostschweizerische Kraftwerke AG
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Enclosures:
wiring diagrams