Part 21 Report - 1999-050

LICENSEE: ROSEMOUNT NUCLEAR INSTR.

OPS OFFICER: JOHN MacKINNON

10 CFR SECTION: CCCC UNSPECIFIED PARAGRAPH

Notification under 10 CFR Part 21 for Rosemount Model-1153B Alphaline Nuclear Pressure Transmitter

Rosemounts Nuclear Instruments, Inc., (RNII) discovered two errors contained in the Rosemount Specification and Outline Dimension Drawings for Model-1153 Series-B Alphaline Nuclear Pressure Transmitters. The first error exists in the Specification and Outline Dimension Drawings for all 1153 Series-B Model types (refs. a - d). In each of these drawings, the module qualified life and electronics qualified life shown in Figure 2 are in error. The graphs of Qualified Life vs. Ambient Operating Temperature were incorrectly transposed from ref. E in June of 1985. This error resulted in overstating the qualified life of both the module and the electronics. Model-1153 Series-B Qualification Report (ref. E), Product Data Sheet (ref. F), and Product Manual (ref. G) are all correct, and the error is contained only in the Specification and Outline Dimension Drawings.

The second error exists only in the Specification and Outline Dimension Drawings for Differential Pressure Transmitter, Model 1153DB (ref. b). In paragraph 4.2.2, the accuracy of the output code "R" following to 22 megarads TID of gamma radiation exposure is incorrectly stated as +/- 1.5% of Upper Range Limit. The correct accuracy value should be +/- 4.0% of Upper Range Limit following exposure to 22 megarads TID gamma radiation exposure. This was a transposition error which occurred in the most recent revision of ref. B on June 27, 1997. The Model-1153 Series-B Qualification Report (ref. e), Product Data Sheet (ref. f), and Product Manual (ref. g) were not affected by this error and are stated correctly.

All affected specification drawings will be revised within 60 days to reflect the correct qualified life vs. temperature relationships as well as output code "R" accuracy. No further action related to this issue is expected.