1. Gerald I. Forstater, PE, PSP, CET and Daniel H. Broughton, EIT
Fire Protection of mission critical 13kv Redundant Switchgear in buildings
Gerald I. Forstater, PE, PSP, CET
and
Daniel H. Broughton, EIT

2. Defining the Problem Dual redundant switchgear 12.47 kV each side
1600 amps per phase – amps total
Enclosed in building
Business continuity

3. Codes, standards & References
IBC – International Building Code, 2012
IFC – International Fire Code, 2012
NFPA – Pamphlet 13 Automatic Sprinkler Systems, 2010
NFPA – 2001 Non-Halogenated Gas Systems, 2010
NEC – 70 Electrical Code, 2010
NFPA – 72 Fire Alarm and Signaling Systems, 2010

4. NSA's Data Center Electrical Problems Aren't That Shocking
By Tekla Perry Posted 16 Oct 2013 | 18:01 GMT
Last week, the Wall Street Journal reported that arc-fault failures – electrical problems that exceed the protective capabilities of circuit breakers and cause metal to melt and go flying – are delaying completion of the NSA’s controversial new Utah data-storage center.
"A circuit breaker tries to open up, but the amperage is higher than it can handle, so when the contacts open it doesn’t break the circuit. Instead, you have an arc that is moving around between the contacts; it has huge magnetic forces to it, and it can’t be easily extinguished. You end up with molten metal flying around which is extremely dangerous."

5. arcing

6. Potential Heat Release Rates
Three phase Fault – 20 MW
One phase fault – 6.67 MW

7. Transformer Failure

8. Internal Arc

9. BUILDING FIRE PROTECTION ANALYSIS

10. BUILDING FIRE detection Pre-action actuation ANALYSIS

11. Detector Response Time
Anticipated detector activation sequence upon fault:
Linear heat detector
Incipient smoke
Spot Heat detector
Smoke detector
Sprinkler head element
Many additional variables
Enclosure gasketing
Rain guards
Ceiling slope
Ventilation
Calculations based on heat from fire not electrical

12. NFPA 2001 over 480 volts
Covers the use of clean agent for Class C fires under 480
Over 480 volts subject to testing if equipment is to stay energized during and after discharge
Recommends the minimum design concentration for Class C fires be 1.35 times the Class A concentration
Class A: 4.5% concentration for most products
Class C: 6%
Other considerations
Low leakage building
Pressure testing
Redundant agent supply
No occupancy during discharge
Post discharge purge

13. AHJ’s, Testing & Acceptance
Conversation with Mr. Rivers of 3M about NOVEC
Multiple tests at 6% concentration
Madrid, Spain
South America
No formal test data available
AHJ must accept these international tests to proceed with design
Physical testing of a similar design at same concentration needed to confirm design

14. Final recommendations
Suppression
Sprinklers to protect building
Pre-action with double interlock
Detection
Incipient smoke detection
Linear heat detection
Ion/photo smoke detectors
Spot/compensated heat detectors
Cross zoning

15. questions PROFESSIONAL SYSTEMS ENGINEERING, LLC
30 YEARS + STRATEGY + SPECIFICATIONS + TECHNOLOGY

16. Next study phase Temperature Set Points Real world Investigation
Actual Test

17. THANK YOU! PROFESSIONAL SYSTEMS ENGINEERING, LLC
30 YEARS + STRATEGY + SPECIFICATIONS + TECHNOLOGY