I still don't understand critical power systems

mbrooke

Batteries Not Included
Location
United States
Occupation
*
Why do health care facilities almost always have only one generator branch running to critical care areas? Why do so many older facilities lack normal branch power in OR, ERs and ICUs? 😳 And appearing to be more out of design rather than capitol economics?


Case in point: ~ 1.2 million square foot hospital. 2 600kw and 1 400kw generator. One critical branch, one none bypass ATS, generator maintenance leaves critical branch without backup power and both normal/critical branches originate from the same unit substation bus section despite several substations/multiple MV utility feeds being present in the same building. The other two generators feed elevators, chillers, imaging, servers, boilers, ect but no life support equipment. Elevators have a manual transfer switch downstream to allow for service of the automatic one.



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romex jockey

Senior Member
Location
Vermont
There appears to have been some changes to 517.29.....also some nfpa ref's that blow us outta the book.....

517.29 Essential Electrical Systems for Hospitals and Other
Health Care Facilities
.

(A) Applicability. The requirements of Part III, 517.29
through 517.30, shall apply to critical care (Category 1) and
general care (Category 2) hospitals and other health care facili‐
ties using Type 1 essential electrical systems where patients are
sustained by electrical life-support equipment.

Informational Note No. 1: For performance, maintenance, and
testing requirements of essential electrical systems in hospitals,
see NFPA 99-2015, Health Care Facilities Code. For installation of
centrifugal fire pumps, see NFPA 20-2013, Standard for the Instal‐
lation of Stationary Pumps for Fire Protection.

Informational Note No. 2: For additional information on Type 1
and Type 2 essential electrical systems, see NFPA 99-2015, Health
Care Facilities Code
.
~RJ~
 

mbrooke

Batteries Not Included
Location
United States
Occupation
*
maybe this helps?>
~RJ~
Here is another example, the 15kv part of the essential system is encased in concrete totally separate from the normal system. As is the life safety. But the 480 volt normal, critical and equipment branches are run side by side. :mad:


 

Todd0x1

Senior Member
Location
CA
How close are the three buss ducts in the actual installation? Could one of them burning down damage the adjacent ones?
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Looks like (appears like) they are harmonizing the health care portion of NFPA 70 with NFPA 99?
NFPA 99 is the controlling document for the performance of the heath care facility electrical system. 99 set the rules on what the system has to do, and 70 has to comply.
 
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