Document: NUREG-0800
Document ID: 805f7e09-51a2-413b-92af-e23bb9073497
Document Type: srp
Title: NUREG-0800
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070493.pdf
Revision Date: 2023-06
Chapter: 8
Section ID: 8
CFR Part: 
CFR Title: 

Content:
out for repair, maintenance, or otherwise unavailable) be available on which to base his decisions.56 8A-19 DRAFT Rev. 3 - April 1996 2B. BRANCH TECHNICAL POSITION 2.1. Diesel-generator unit bypass or deliberately induced inoperability status should be automatically indicated in the control room where the bypass or deliberately induced inoperable condition can be expected to occur more frequently than once per year and can render the unit unavailable to adequately respond to an automatic or operator-initiated emergency startdemand signal (e.g., nonreset, mode switch position, loss of control 57 voltage, low starting air pressure). Manually induced indication may be desirable and is 58 permitted for diesel-generator unit bypass or deliberately induced inoperability status for those conditions expected to occur less frequently than once per year. 2.2. All status indication should be sufficiently precise to prevent misinterpretation. Further, disabling or bypass indicators should be separate from nondisabling indicators and should be physically arranged to enable the operator to clearly determine the status of each diesel-generator unit. An acceptable design would include a separate alarm for each disabling condition or a single shared alarm with reflash capability. The alarms should be displayed in the control room and at the diesel-generator unit for all disabling conditions, with wording that indicates that the diesel-generator unit is incapable of adequately responding to an automatic start signalemergency demand . 59 2.3. When a shared diesel-generator unit can be bypassed, indication of that bypass condition should be provided in the control room of each affected unit. 2.4. The indication system should be designed and installed in a manner that precludes the possibility of adverse effects on the diesel-generator units. Failures in the indication equipment should not result in diesel-generator unit failure or bypass of the diesel-generator unit, and the bypass