ML19249F073
| ML19249F073 | |
| Person / Time | |
|---|---|
| Issue date: | 09/05/1979 |
| From: | Gammill W Office of Nuclear Reactor Regulation |
| To: | Jordan E NRC OFFICE OF INSPECTION & ENFORCEMENT (IE) |
| References | |
| RTR-REGGD-01.108, RTR-REGGD-1.108 NUDOCS 7910050150 | |
| Download: ML19249F073 (2) | |
Text
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SEP 5 1979 MEMORANDUM FOR:
E. L. Jordan, Assistant Director, Division of Reactor Operations Inspection FROM:
W. Gammill, Assistant Director for Operating Reactor Projects, Division of Operating Reactors
SUBJECT:
PROPOSED BULLETIN-POTENTI AL FAIL;RE OF EMERGENCY DIESEL GENERATDR FIELD EXCITER TRANSFCt.MER We have reviewed the draft of the subject proposed IE Sulletin and herewith submit our comments for your consideration.
COMMENTS
- 1. On page' 2 of 2,in the second paragraph, the following can be added after the manufacturer's quotation:
"However, removal of the neutral connection can subject the transformer to neutral instability if its loads were not balanced.
It should, therefore, be ensured that the EPT or CPT has balanced loao.
In this context, the connection of other potential transformers (PT's) used at the system interface between EDG and 4Ky bus should also be reviewed for similar problems."
- 2. On page 2 of 2, the first sentence of action 1 could be revised to read as follows:
" Determine, whether or not, there is a connection, directly or thru conmon grounding, between the neutrals of low KVA rated instrument transformers and high KVA rated EDG without adequate limitations on the flow of circulating currents that would cause overheating of the transformers."
- 3. Since the requirements of Regulatory Guide 1.108 have not been implemented on operating plants, it will be advisable to re-write paragraph C.2.a.3 in the action 2 paragraph, rather than referring to the Reg. Guide.
[Ge W. Gamm111, Assistant Director for Ocerating Reactor Projects Division of C'perating Reactors
Contact:
I. Ahmed, X28077
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D. Eisenhut B. K. Grimes F. Rosa G. Lainas
- 0. Tendi V. Thomas M. Chiramal I. Ahmed
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