Title: Hunting Mighty Milliwatts The next technology step enables monitoring of these elusive elements, wit
1Hunting Mighty MilliwattsThe next technology
step enables monitoring of these elusive
elements, with their potentially catastrophic
energy, BEFORE they can cause a major power
failure
- Dr Francesco Pompei PhD Ross Kennedy
- President CEO
- Exergen Corp QHI Group
2What is a Mighty Milliwatt (MmW)?
- Small amounts of resistive energy losses
converted to heat from electrical circuit
elements in high power electrical systems,
usually at connections, manifested as temperature
rise above ambient. - 0.001 Watt in resistive energy lost by circuits
using kiloWatts to megaWatts of power, or less
than 0.0001 of the energy transmitted.
3What is a Mighty Milliwatt (MmW)?
q hr x A x (T - TA) 1 x 1 x 1 .007
Btu/hr-ft2
144 Convert to Watts .007 3.4 .002 Watts
2
Milliwatts
4What Creates a Mighty Milliwatt ?
Resistance and Current! ? Mighty milliwatts ?
Manywatts
V Voltage Volts R Resistance ? I Current
Amps
P I2 x R Heat Dissipated as mW Calculate R
for 2 mW (1F Rise) For 100 Amp Cable P .002
I2R (100)2R R .002 .002 .0000002
? (100)2 10,000
2
10,000,000 An OHM Meter
Wont Work Too Well!!
5What Can a Mighty Milliwatt Do?
Suppose the connection loosens with time and
oxidation to R ? 1 ? ? For 100 Amp Circuit Power
I2 R (100)2 (1) 10,000 W 10 kW
Mighty MilliWatt turns into 10 kW, enough energy
to melt 1 ounce of copper in 0.6 seconds -gt
Catastrophic Failure
6How does that Happen?
When the Resistive Loss exceeds a threshold
value, the temperature increase causes rapid and
irreversible increase in R, triggering positive
feedback system that leads to Complete Failure of
the connection.
7How does that Happen?
LOG POWER
Fraction of Second
TIME
Moment of Truth
If the cause of the resistive loss is not
corrected at a safe threshold, there is a risk
that the runaway positive feed back will occur.
8How do we find Mighty MilliWatts?
- The resistive energy is lost approximately ½ by
radiation and ½ by convection to the local
environment. - The radiation component is detectable by infrared
radiation methods of sufficient sensitivity and
reliability as temperature rise above ambient.
9Continuous monitoring is required
?
?T P I2R
Temperature rise is very sensitive to load.
Factor of 3 in load changes ?T by factor of 10
- Scheduled scans will not be at the peak load for
all locations. - Scheduled scans will not detect the moment of
truth. - Scheduled scans will not provide rate-of-change
data.
10Requirements for Continuous Monitoring
- Small, simple, reliable IR sensors inherently
measuring temperature rise above ambient. - Can be placed at a safe distance inside cabinets.
- Negligible metallic cross-section.
- Self-powered
- Local signal conditioning outside of electrical
panels. - Wired or wireless data transmission to monitoring
computer. - Appropriate software
11 IRt/c Sensor
12Self-powered intrinsically safe sensor
mV c (TT Ts ) c (TT TA ) When Ts
TA
Inherently measures the rise above ambient with
only the assumption that the sensor body is at
the same temperature as the local ambient.
13Self-powered intrinsically safe sensor
Drift-free passive electronic components,
maintains accuracy over long periods in harsh
environments, MBTF 1000 yrs.
14- How Serious is this Problem ?
- What is the probability of occurrence
- What are the likely downtime effects
- What benefits does new technology bring ?
15- Some Answers How serious is the problem
- Bad terminations are the single greatest
cause of
electrical failures Arc Flash - Estimates vary but there appears consensus
there are up to 10 Arc Flash explosions / 30
incidents resulting injuries PER DAY ! - Average deaths from direct contact with live
switchgear / busbars/ fuses etc - 15 DEATHS per YEAR
- (source Bureau of Labor Statistics
industry)
16- Seriousness scale of problem recognised
resulted in NFPA code 70 E - Attempts to mitigate death / injury AFTER the
event via zoning / PPE
17AFCOM Survey
Source Data Center Institute
5
13
53
29
Do you think you will need to physically expand
your data center and/or outsource some
applications in the next 10 years?
18AFCOM Survey
Source Data Center Institute
If yes, why?
19By the numbers
81.2 82.5 20.5
Number of AFCOM members experiencing a data
center failure in the last 5 years. Number of
failures caused by power outages, internal and
external. Number of AFCOM members experiencing 5
or more outages in the last 5 years.
Source Data Center Institute
20Example 2005, Uptime Institute review
Source Data Center Institute
Reviewed 19 data centers
Findings
- Most centers cannot properly cool the equipment
currently installed (saying nothing about the
high density equipment ) - Average power consumption per rack was 2.1
Kilowatts (KW) (fully populated rack can produce
12 -14 KW, 6 times that of which they are now
having trouble cooling - Air Intake temps at 10 of the racks exceeded
the server reliability guidelines
21Some Answers
Over next 5 years power failures limitations on
power availability will halt data center
operations at more than 90 of Companies
Source Data Center Institute
22Probability of Failure of key power systems
infrastructure configurations
99.52 26.32 19.85
12.95
Source Data Center Institute
23-
- Even tier IV are susceptible to
disruption during maintenance - If intervention maintenance can be
extended by just 1 year - ( If it aint broke dont fix it
!) - That alone ensures payback within 1st year of
install.
24- Cost of litigation / settlement
- Death 3 gt 15.75 Millon per case
-
(source Dr R. Wyzga EPRI study 1999 ) - Downtime the MTTR myth In Arc Flash
situation cannot apply standard MTTR. - 1 gt 2 days to assess average min say 5 weeks
840 hours -
(source D. Fortner industry interviews
July 2007)
25Source Data Center Institute
26- Downtime cost Average 100k p/hr
-
(sourceData Center
Institute) - Probability Cost 100k p/hour x 840 hrs
- 84,000,000 exposure risk
27-
- Typical data center build cost circa 150m
- Power system typically represents circa 33
- Continuous thermal monitoring system typically
represents circa less than 0.5 of power system
cost
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29(No Transcript)
30 IRt/c Sensor New Technology Benefits
31Data acquisition Card
32Integration Options
Stand alone PC
Stand alone common alarm to BMS
Direct connection to BMS
Remote wireless data transfer
Connection via Ethernet
33BMS Integration, access through a browser
34Power System Schematic
35I/R and cable sensors
36Cable sensors
37Cable sensors
Cable sensors
38 Comparison
- Existing New
- Inspection 1/365 365/365
- Position External Internal
- View Limited Unlimited
- Reliability dependant on Luck
- / interpretation Continuous reliable
- Arc Flash (window) Risk No Risk
- data
- Availability Not real time Real time / on-line
39- Why take a
- Snapshot
- when you can now have the
- Whole Picture ?
40Company Information
QHi-Group
44(0)1582 461123 sales_at_qhigroup.com www.qhigroup.
com