ML18319A064

Degraded Voltage La Potential RAIs

ML18319A064
Person / Time
Site:	Hatch
Issue date:	06/15/2018
From:	Joyce R Southern Nuclear Operating Co
To:	Randy Hall Plant Licensing Branch II
Hall R,
References
Download: ML18319A064 (1)

Text

From: Joyce, Ryan M.

To: Hall, Randy

Subject:

[External_Sender] RE: Degraded Voltage LAR potential RAIs Date: Friday, June 15, 2018 2:36:02 PM Attachments: Vendor Manual.pdf The manufacture and model number of the Degraded voltage relays are ABB 27N Model No.

411T5375-HF. I understand that the vendor manual for these relays is publicly available, however, its also attached.

Thanks.

From: Hall, Randy [1]

Sent: Thursday, June 14, 2018 2:02 PM To: Joyce, Ryan M. <RMJOYCE@southernco.com>

Subject:

Degraded Voltage LAR potential RAIs

Ryan, As we discussed, the staff is currently preparing RAIs for the subject LAR, but the question below may be something that can be quickly answered, and may not need to be asked as a formal RAI.

In the LAR, the licensee requested to add the Allowable Values (AVs) into Function 2, 4.16 kV Emergency Bus Undervoltage (Degraded Voltage), that includes Function 2.a (Bus Undervoltage) and 2.b (Time Delay). There are new AVs specified for the new Degraded Voltage Relays (DVRs). Please provide the manufacturer name and the specific model number of the relays which will be used to accomplish the safety functions associated with these proposed DVRs.

Also, is there a vendor brochure or catalog publicly available that we can look at to determine input and output parameters, accuracy, tolerances, etc., for the new relays?

Thanks, Randy Randy Hall, Senior Project Manager Plant Licensing Branch II-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation USNRC (301) 415-4032 Randy.Hall@nrc.gov