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IEEE TRANSACTIONS ON POWER DELIVERY 1
Electrical Safety of Street Light Systems
Giuseppe Parise, Fellow, IEEE, Luigi Martirano, Senior Member, IEEE, and Massimo Mitolo, Senior Member, IEEE
Abstract—Street light systems are publicly accessible electrical
pieces of equipment out of the physical control of who operates/
owns them. Street lighting systems typically include low-voltage
loads, distributed in a large area, and are collectively protected
by the same device. Under fault conditions, hazardous potentials
may appear on the metal enclosures of these systems, and expose
people to shock hazards. To reduce the risk to an acceptable level,
different solutions for the bonding and grounding are available.
The Standard IEC 60364 and a current worldwide tendency seem
to encourage the use of Class II equipment for the street light sys-
tems. Class II components, such as the wiring systems, the light
fixtures, etc., have double or reinforced insulation. In this paper,
these authors analyze technical alternatives to protect against in-
direct contact in light of the IEC standards. In order to elevate the
level of safety offered by Class II metal poles, the adoption of spe-
cial circuitry and bonding connections to continuously monitor the
double insulation of metal poles is proposed.
Index Terms—Earth, exposed-conductive-parts, extra-
neous-conductive-part, grounding electrode, light pole, neutral
residual current device, street lighting system, TI system, TN
system, TT system.
I. INTRODUCTION
STREET lighting systems are a typical case of distributed
low-voltage loads located in large areas, and collectively
protected by the same device. In most cases, lighting systems of
streets, parkways, and other public areas are under the respon-
sibility of electrical utilities. Utilities maintain and operate the
system and ensure safe illumination during the hours of dark-
ness (approximately 4000 h/yr).
Luminaries may be mounted on steel or wooden poles, fed
with underground cables, originating from the nearest avail-
able distribution line. Typically in the U.S., the single-phase,
three-wire, 120/240 V, or the three-phase, four-wire, 277/480 V
are adopted; in Europe, the single-phase, two-wire, 230 V, or
the three-phase, four-wire, 400/230 V distribution systems are
typical.
Technical standards of the International Electrotechnical
Commission (IEC) specify the use of Class II equipment for the
street light systems as the protection against indirect contact.
Class II components, such as the wiring systems, the light
fixtures, etc., have a double or reinforced insulation. In normal
operating conditions and for properly maintained systems,
Manuscript received October 21, 2010; revised February 16, 2011; accepted
March 15, 2011. Paper no. TPWRD-00806-2010
G. Parise and L. Martirano are with the Department of Electrical Engineering,
University “La Sapienza,” Rome 00184, Italy (e-mail: parise@ieee.org; arti-
rano@ieee.org).
M. Mitolo is with the Electrical Department of Chu and Gassman, New York,
NY 08846 USA (e-mail: mmitolo@chugassman.com).
Color versions of one or more of the figures in this paper are available online
at http://ieeexplore.ieee.org.
Digital Object Identifier 10.1109/TPWRD.2011.2131690
the risk of breakdown of both layers of insulation is deemed
extremely low.
However, double insulation of Class II components of street
lighting systems may actually fail during their life-cycle. This
may be caused by lack of maintenance due to their possible large
extension, as well as by their critical operating conditions, such
as, for example, car impacts or animal intrusions into poles. As
a consequence, the loss of the double insulation of components
within metal poles, which may go undetected if the leakage cur-
rent is below the trip setting of protective overcurrent devices,
exposes people to the risk of electric shock.
In this paper, the authors discuss possible alternatives for the
protection against indirect contact in light of the aforementioned
IEC standards. In addition, to increase the level of safety offered
by Class II metal poles in different grounding systems, the au-
thors propose the adoption of special circuitry and bonding con-
nections to monitor continuously the status of their double in-
sulation. Throughout the entire paper, the terms “ground” and
“earth” are used as synonyms.
II. PROTECTION AGAINST INDIRECT CONTACT
AND TYPES OF GROUNDING SYSTEMS
In low-voltage (LV) systems, the protection against indirect
contact may be achieved by automatic disconnection of the
supply. This measure calls for the grounding of the neutral of
the LV supply, as well as of the enclosures of equipment, also
referred to as exposed conductive parts (ECPs). This grounding
is preferably carried out through an earthing electrode common
to source and loads (i.e., the TN system), but can also be
achieved through two independent grounding systems (i.e.,
the TT system). To further clarify the differences among the
TT, TN, and IT grounding systems, explanatory figures are
provided in the Appendix.
The different types of grounding systems are codified by IEC
60364 through the XY-Z acronyms (Table I). This codification
allows the introduction of the TI grounding system, which is not
formally defined in IEC standards.
In the XY-Z acronym:
• the X-letter describes the condition of the neutral point of
the grounding of power-supply global positioning system
(GPS) with respect to ground:
direct connection of source neutral to earth;
neutral is ungrounded, or grounded through an
impedance.
• The Y-letter describes the condition of the exposed con-
ductive parts (ECPs) with respect to ground:
•
0885-8977/$26.00 © 2011 IEEE
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2IEEE TRANSACTIONS ON POWER DELIVERY
TABLE I
GROUNDING SYSTEMS ACRONYMS DEFINED BY IEC.
Fig. 1. TN-S system: protective conductors (PE) are connected to the power-
supply ground electrode.
connection of the ECPs to ground, independent
of the GPS;
connection of the ECPs to GPS;
ECPs are not connected to GPS.
• The Z-letter (if any) describes the arrangement of neutral
and protective conductors (PE):
neutral wire and PE are separated;
neutral wire and PE are combined in a single
conductor (PEN).
Based on the previous text, the TI grounding system is charac-
terized by grounded power supplies and by ungrounded metal
enclosures of equipment.
Low-voltage loads are usually supplied by radial distribu-
tion systems. A basic solution is the TN system, where all of
the simultaneously accessible ECPs must be connected to the
grounding of the power supply via protective conductors. The
TN-S is a practical solution when the LV loads are concentrated
in the same area as the MV/LV substation (Fig. 1).
In TN-S systems, the three-phase distribution line consists of
five-wire (H-H-H-N-PE), whereas the single-phase distribution
line consists of three-wire (H-N-PE). In both cases, the protec-
tive conductor and neutral wire are distinct conductors (Fig. 1).
Extraneous-conductive-parts (EXCPs) must also be bonded
to the main earthing terminal of the building, as close as possible
to their point of entry within it. EXCPs may include metallic
parts of the building structure, metal pipe systems for gas, water,
heating, and noninsulating floors and walls [8].
Note that in the IEC approach for LV power systems, the
use of the TN system is possible only if the user owns the
MV/LV substation. In this case, the service entrance is supplied
by the utility at medium-voltage. Consequently, in residential
or small commercial applications, powered by utility-owned
transformers, only the TT system can be implemented.
Where street lighting systems are in areas where it may not
be possible, or practical, to implement either the TT or the TN
system, the adoption of Class II components for all the elements
of the lighting system (e.g., poles, light fixtures, cables, splices,
terminal strips, etc.) is an alternative approach. Class II compo-
nents have double, or reinforced, insulation: protections against
direct contact (also referred to as basic protection) and against
indirect contact (also referred to as fault protection) are, respec-
tively, provided by the basic and the supplementary insulations.
Reference [1] defines as Class II, the metal poles whose hand-
hole cover on the lighting column is separated from wires by
insulating material (e.g., sleeves or tubes).
In this case, [1] does not require the intentional earthing of the
conductive parts of the lighting column; thus, protective conduc-
tors are not provided in the electrical distribution system.1
III. TT STREET LIGHTING SYSTEM
In low-voltage TT systems (generally used in Europe) the
distribution line is carried out through four-wire (H-H-H-N)
or two-wire (H-N for single-phase loads) systems, generally at
400/230 V (or 380/220 V), and at 50 Hz.
At the service panel, a protective conductor (PE) is locally
earthed, and kept separate from the neutral wire. Downstream
the service panel, the local distribution system consists of a five-
wire system (H-H-H-N-PE for three-phase loads) or a three-
wire system (H-N-PE for single-phase loads).
For TT systems, all ECPs collectively protected by the same
feeder protective device (FPD) must be connected to a common
earth electrode [3]. However, if in addition to the FPD, local
protective devices (LPDs) are used for each pole or group of
poles, independent grounding systems may be allowed (Fig. 2).
In the TT system, ground-fault currents are greatly limited by
the earth resistance of the earth electrodes; the fault loop also
includes the earth resistance of the utility substation. Thus, a
protective overcurrent device may not trip within the maximum
permissible times [5], since the magnitude of the ground-fault
current might be below the threshold of its long time pickup.
Thus, in TT systems, residual current devices (RCD) must nec-
essarily be employed. In the TT system of Fig. 2, protection
against indirect contact is achieved by using RCD at a level of:
• FPD in case of a common earth electrode [Fig. 2(a)];
• LPD in case of independent earth electrodes; in this case,
FPD may have a delayed instantaneous tripping time (no
higher than 1 s) [Fig. 2(b)].
IV. TN-C-S STREET LIGHTING SYSTEM
In low-voltage TN-C-S systems (generally used in North
America), the distribution line is carried out through a four-wire
(H-H-H-PEN) three-phase, or three-wire (H-H-PEN), double
1The absence of equipment grounding conductors in particular cases, such as
double-insulated appliances, is a concept also present in [2] (Art. 250.114 Ex),
adopted in the U.S.
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PARISE et al.: ELECTRICAL SAFETY OF STREET LIGHT SYSTEMS 3
Fig. 2. (a) TT system with light poles collectively protected by the same FPD
and (b) independently protected by local protective devices LPD.
Fig. 3. TN-C-S systems: the PEN conductor acts as a grounded conductor and
as an equipment grounding conductor.
single phase. In these systems, the PEN conductor acts as a
grounded conductor and a PE (Fig. 3).
The system becomes a TN-S system downstream the user
panel, where a separate protective conductor PE originates. At-
tention is drawn to the fact that in the TN-S portion of TN-C-S
systems, the PE must not pass through the RCD’s toroid, so that
fault currents will not circulate through it and possibly desensi-
tize it, invalidating its protection.
V. TI STREET LIGHTING SYSTEM INTEGRATED WITH A
RESPONSIBLE MAINTENANCE
In TI systems (generally used for street lighting system in
Italy), the electrical distribution line consists of a four-wire
(H-H-H-N) three-phase, or two-wire (H-N) single-phase
system. The neutral point of the source is grounded, whereas all
of the electrical components are Class II, and are ungrounded
(Fig. 4). In this case, the FPD may be an overcurrent protec-
tive device. Each electrical component of the TI system must
guarantee the double insulation, not only by construction,
but also by installation. Steel poles supported by concrete
plinths have an optimal mechanical resistance against natural
events (e.g., high winds, thunderstorms, ice accumulation, etc.)
and accidental events (e.g., car impacts). Let us note that in
a TI system, each component, such as switchgears, cables,
luminaries, terminations, joints (straights and 90 ), etc, must
Fig. 4. In TI systems, the neutral point is grounded and the poles (potential
ECPs) are Class II.
Fig. 5. Cast polyurethane resin splice for Class II, multicore plastic
insulated cables.
guarantee double insulation characteristics (Class II), both
by construction, as shown in datasheets, and by installation
(adopting special requirements).
It is, in fact, important that the installation of Class II equip-
ment (especially branch joints and connections) should not
compromise the protection prescribed in the specifications for
double insulated equipment.
For example, the installation of Class II, multicore, plastic
insulated cable splices, used to derive the branch circuit in the
handhole at the pole, requires special materials and techniques
(Fig. 5).
For the street light electric distribution systems, IEC stan-
dards promote the TI system, which does not call for the RCDs;
this solution avoids nuisance tripping that could determine un-
safe conditions especially in areas at high vehicular traffic.
The disadvantage of this arrangement is that if the double
insulation fails, the TI system degrades to a TT system; there-
fore, overcurrent protective devices may not clear the fault for
the reasons examined in Section III. Thus, in this case, mainte-
nance implies a higher responsibility for the owner of the street
lighting system.
If, for instance, the double insulation of the luminaire termi-
nals fails due to, for example, an incorrect lamp replacement
(Fig. 6), the surface of the metal pole may become permanently
energized, exposing people to the risk of electric shock, until a
maintenance crew detects the failure.
Actual earth measurements carried out in TI systems show
that a 10 m steel pole, whose foundation plinth is embedded in
the ground for 0.8 m (Fig. 7), offers relatively high values of
resistance-to-ground. If, for example the pole earth resistance
assumes a value of , in TI street lighting systems supplied
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4IEEE TRANSACTIONS ON POWER DELIVERY
Fig. 6. Luminaire terminations with faulty double insulation.
Fig. 7. Typical street light pole.
at 400/230 V, the earth fault current caused by the faulty double
insulation will not exceed 11 A.
The metal pole can assume almost the whole supply value of
230 V, which is permitted for no more than 0.2 s. The ground
current may be even lower, if we consider the limitation effect
caused by the arc impedance. Arc faults to ground, in fact, are
more likely to occur than bolted faults in ac low-voltage sys-
tems.
Consequently, it would be advisable to implement a mainte-
nance program to:
• periodically inspect the publicly exposed lighting system
to confirm the absence of damages to the structures;
• periodically test the insulation between live conductors and
earth, as per the conceptual diagram presented in Fig. 8.
The insulation-to-ground of the system will pass the test if
upon the application of a voltage of 500 V for 60 s, the resistance
measured is greater than:
•, if the test is conducted with all the luminaries
disconnected (very unpractical);
•, if the test is arranged with all the lumi-
naries connected; where L is the length in kilometers of
Fig. 8. Conceptual representation of the ground insulation test for single-phase
circuits supplying poles.
Fig. 9. Feeder within the panelboard is disconnected from the CB for the insu-
lation-to-ground test.
the line, with a minimum of 1 km, and N is the number of
luminaries.
For example, for a system with an extension not exceeding 1
km, which supplies 30 luminaries, the minimum value of the in-
sulation resistance is about ; a leakage current of about 3.5
mA at 230 V corresponds to this value of insulation resistance.
Although conceptually simple, the aforementioned procedure
is rather complex to perform, because the personnel must tem-
porarily drive an auxiliary ground rod, not always an easy task
in urban areas, and disconnect the feeder within the panelboard
(Fig. 9).
Attention is drawn on the fact that [1] states that metal struc-
tures (such as fences, grids, etc.), which are in the proximity
of the street lighting system, but do not form part of it, need
not be connected to the earth terminal of the installation. This
requirement applies to any outdoor lighting installation, regard-
less of the type of grounding system adopted. Reference [1] does
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PARISE et al.: ELECTRICAL SAFETY OF STREET LIGHT SYSTEMS 5
not clarify whther the aforementioned metal structures that are
EXCPs constitute an exception and should be earthed.
VI. PRACTICE IN THE U.S
Reference [2], adopted in the U.S., prescribes that conduc-
tive enclosures of light poles be connected to the facility ground
system through an equipment ground conductor in the same
raceway as the line wires. However, not all light street systems
are installed per [2].
Outdoor lighting installations mounted by utilities are, in
fact, in compliance with [9], which does not require protective
conductors to bond the conductive poles. In some systems,
the safety of steel, or aluminum, poles is exclusively entrusted
upon local ground rods connected to each pole, without any
bonding connection to the source or to the other poles.
The resulting system is a TT, which may not necessarily have
its characteristic safety requirements, such as a very low earth
resistance for the single electrodes and/or the RCDs. Thus, low-
intensity ground faults might not be cleared at all, causing the
permanent presence of stray voltages on publicly exposed en-
closures.
This earthing arrangement is unsafe and, in fact, is not
permitted by [1], as mentioned in Section III. Details on the
safety reasons behind this prohibition have been discussed in
[5]. Modern systems use a three-wire, or four-wire distribution
line, which does include a ground wire. The ground conductor
is bonded to the metal pole. The earth electrode system is
usually a ground rod, or a concrete-encased electrode obtained
by using the re-bars of the plinth of the pole, connected at the
service point.
The City of Los Angeles Street Lighting Guide, for example,
states that overcurrent devices (i.e., fuses or circuit breakers)
without ground-fault protection shall protect all street lighting
systems. When circuit breakers are used, the neutral wire shall
only be grounded at the service point, and an additional equip-
ment ground conductor shall be employed to bond together all
steel components of the lighting system [7]. The aforementioned
arrangement constitutes a TN-S system.
As a further example of good practice, we can consider the re-
quirements of the Louisiana Highways Lighting Systems, which
prescribes that: “an equipment grounding conductor shall be in-
stalled with each new circuit and shall be connected to each new
light pole and fixture.”
In New York City, the chronic problem of stray voltages ap-
pearing on metal poles is being mitigated by installing noncon-
ductive composite covers on utility service boxes, and intro-
ducing isolation transformers [5] within the poles.
These transformers allow the galvanic separation of the
lighting circuit from the earth, thereby preventing the circula-
tion of currents, if the basic insulation of the circuit, or of other
components within the pole, fails.
In addition, the utility has also developed a mobile detection
vehicle (MDV) that can survey for stray voltages on metal poles
while driving down the streets. MDVs are used to conduct an-
nual surveys and prior to public events to enhance public safety.
VII. PROPOSED SOLUTIONS
The authors suggest two types of solutions, applicable in al-
ternative or combined, to improve the TI system:
1) an additional level of protection extended to all the com-
ponents of the street light system;
2) a smart solution localized within the panelboard.
A. TI System With an Additional Level of Protection
Considering the basic benefits for safety of the double insula-
tion, but also the difficulties in detecting its failure, the authors
suggest, as extra levels of protection (Fig. 10), the addition of
a residual current relay within the protective device and, one or
both, of the following:
• employment of multiconductor cables with an integral pro-
tective conductor to reduce the risk of its accidental discon-
nection;
• addition of a buried bare grounding wire to be connected
to each metal pole in TI systems.
The bare grounding wire will have a minimum cross-sectional
area of and be buried at a minimum depth of 0.50 m
below grade. This additional earth electrode will integrate the
natural electrode constituted by the plinth.
In this arrangement, the protection against indirect contact is
guaranteed by two levels:
• a first level consisting of double insulated components;
• a second level consisting of the disconnection of the supply,
or the activation of an alarm, in the case of failure of the
double insulation.
B. “Smartpanel” with an Insulation Monitoring Device
As explained in Section V, although conceptually simple, the
maintenance in the TI system is rather complex, due to the prac-
tical difficulties setting up the insulation test circuit.
To facilitate the testing procedure, and drastically reduce
its costs, the authors propose the adoption of a “smartpanel”
equipped with a special insulation monitoring device (IMD).
The special IMD is composed of:
1) a permanent testing circuitry consisting of a double-insu-
lated test switch and a ground test electrode permanently
installed in an inspection well (Fig. 11).
The test switch has two positions: “power” and “test,” sep-
arated by an “open” status. The “power” position allows
the normal supply of the light fixtures. The “test” position
shorts together the live conductors, allowing the insulation
test.
When the switch is in test position, the insulation tester
(indicated as Mohm in Fig. 10) is connected to the live
conductors and to the test electrode. Two connection ter-
minals are available at the smartpanel to accept the insula-
tion tester leads.
2) The insulation tester can be either enclosed in the panel
or external and portable. If the Mohm is enclosed in the
panel, the insulation test can be performed on a daily basis
without personnel involvement, thanks to a contactor that
automatically turns the test switch in the “test” position. If
the Mohm is portable, the insulation test is manual and has
to be performed by maintenance personnel.
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6IEEE TRANSACTIONS ON POWER DELIVERY
Fig. 10. The grounding electrode only operates upon failure of the double insulation (TT system).
Fig. 11. Panelboard equipped with the test switch and accessible ground test
electrode.
3) A transmitter system (e.g., GSM, GPRS, or power-line
communication (PLC)), capable of sending the testing data
to the maintenance center, allowing a continuous and cost-
effective maintenance activity.
The aforementioned solution adds extra cost to the utility,
which is estimated in an additional expense not exceeding
50% of the panelboard cost. However, this extra expendi-
ture would drastically reduce maintenance activities and
greatly increases public safety.
TABLE II
COMPARISON AMONG THE DIFFERENT SMART SOLUTIONS
Note that the new generation of lighting smartpanels is al-
ready equipped with transmitter interfaces, so that the addi-
tional cost reduces to the test switch and the test electrode.
C. “Smartpanel” with Residual Current Monitoring Device
To further increase the public safety, the smartpanel could be
equipped with a residual current monitoring device (RCMD).
The RCMD consists in a residual current relay that can initiate
a local alarm and send an automatic notification to the mainte-
nance center, without disconnecting the supply to the lighting
system. The RCMD should be protected against surges, and
have a residual threshold of not less than 500 mA, to prevent
nuisance trippings.
Table II shows a comparison among the different proposed
solutions by assuming the TI system as the reference.
VIII. CONCLUSION
It has been substantiated that fault loops in streetlight sys-
tems depend on the grounding system employed. The strategy
for the protection against indirect contact must therefore be ac-
cordingly studied.
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PARISE et al.: ELECTRICAL SAFETY OF STREET LIGHT SYSTEMS 7
Fig. 12. TT grounding system.
TT, TI, and TN systems have fault loops of a different nature,
the first two comprise the actual earth, which makes the pro-
tection against indirect contact by disconnection of the supply
based on overcurrent devices difficult.
The TI system is an efficient solution to protect people from
electric shocks and to preserve the continuity of the service, es-
pecially in areas at high pedestrian and/or vehicular circulation.
In fact, the probability that the basic and the supplementary in-
sulations are both punctured is very low, but not zero, if we con-
sider the hundreds of thousands of metal poles present in large
cities. However, forensic cases have been documented (Fig. 6),
proving that this event has occurred.
To reduce this risk, the authors propose testing circuitry to be
implemented within the lighting system panelboard. This cir-
cuitry, thanks to a test electrode, can check the leakage to ground
of the double insulation and alert the maintenance personnel
well before the complete failure of the Class II pole. In addition,
these authors also propose the adoption of grounding electrodes
for Class II light pole systems, beneficial in the case of the un-
detected failure of the double insulation.
Studies to generalize the proposed solutions in the case of
concrete or wooden poles as well as in the case of light systems
in high-resistivity soils will be carried out in the future.
APPENDIX
In TT grounding systems, two independent earthing systems
are called for: one for the source and one for the equipment
(Fig. 12).
In TN grounding systems, the earthing electrode is common
to the source and the equipment (Fig. 13).
In IT grounding systems, the source is not earthed, or is
earthed through a high impedance; the equipment is grounded
(Fig. 14).
For further details, see [3] and [10, ch. 6, 7, and 9].
Fig. 13. TN grounding system.
Fig. 14. IT grounding system.
REFERENCES
[1] 1996-04, 1st Ed., Electrical Installations of Buildings, Part 7. Require-
ments for Special Installations or Locations—Section714: External
Lighting Installations, IEC 60364-7-714, 1996.
[2] ANSI/NFPA 70, National Electrical Code 2008.. Quincy, MA, Na-
tional Fire Protection Assoc.
[3] G. Parise, “A summary on the IEC protection against electric shock,”
IEEE Trans. Ind. Appl., vol. 34, no. 5, pp. 911–922, Sep./Oct. 1998.
[4] M. Mitolo, “Is it possible to calculate safety?,” IEEE Ind. Appl. Mag.,
vol. 15, no. 3, pp. 31–35, May/Jun. 2009.
[5] Low-Voltage Electrical Installations—Part 4-41: Protection
for Safety–Protection Against Electric Shock, 2005, Ed.5, IEC
60364-4-41, 2005.
[6] M. Mitolo, “On outdoor lighting installations grounding systems,” in
Proc. IEEE Ind. Appl. Soc. 41st Annu. Meeting, Conf. Rec., Tampa, Fl,
Oct. 2006, vol. 5, pp. 2224–2229.
[7] Bureau of Street Lighting City of Los Angeles, Design Standard and
Guidelines, May 2007.
[8] M. Mitolo, M. Tartaglia, and F. Freschi, “To bond or not to bond: That
is the question,” IEEE Trans. Ind. Appl., vol. 47, no. 2, pp. 989–995,
Mar./Apr. 2011.
[9] Standard ANSI/IEEE C2-2007, National Safety Electrical Code,
C2-2007, 2008.
[10] M. Mitolo, Electrical Safety of Low-Voltage Systems. New York: Mc-
Graw-Hill, 2009.
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8IEEE TRANSACTIONS ON POWER DELIVERY
Giuseppe Parise (M’82-SM’03–F’10) was born in
Luzzi (Cosenza), Italy. He received the Electrical
Engineering degree from the University of Rome,
Rome, Italy, in 1972.
He has been with the Department of Electrical En-
gineering, University of Rome “La Sapienza” since
1973 and is currently a Full Professor of Electrical
Power Systems. He has authored about 190 papers
and two patents. Since 1975, he has been a Designer
of Power Electrical Systems in Buildings Complexes,
such as in Roma Sapienza University City and Engi-
neering Faculty, Polyclinic Umberto I, Italian Parliament, Campus Biomedical
Research Center.
Prof. Parise received three Prize Paper Awards from the IEEE/IAS Power
Systems Department. Since 1983, he has been a member of Superior Council of
Ministry of Public Works. He is active in IEEE\IAS, Chair of IA Italy Section
Chapter, Member at Large of Executive Board 2007-2010, and is past President
of AEIT Rome’s Section. He is Chair of Electrical Power Systems Researchers
of Sapienza University. He has been a Registered Professional Engineer since
1975.
Luigi Martirano (S’98–M’02–SM’11) received the
M.S. and Ph.D. degrees in electrical engineering
from the University of Rome, Italy, in 1998 and
2002, respectively.
In 2000, he joined the Department of Electrical
Engineering, University of Rome “La Sapienza.”
Currently, he is an Assistant Professor of Building
Automation and Energy Management at the En-
gineering Faculty and of Lighting Systems at the
Architecture Faculty. He is the author or coauthor of
more than 60 papers and a co-inventor of one inter-
national patent. His research activities cover power systems design, planning,
safety, lightings, home and building automation, and energy management. He
is a senior member of the IEEE Industry Applications Society, of the Italian
Association of Electrical and Electronics Engineers (AEIT), and of the Italian
Electrical Commission (CEI) Technical Committees CT205 and SC311B. He
is a Registered Professional Engineer.
Massimo Mitolo (SM’03) received the Ph.D. degree
in electrical engineering from University of Naples
“Federico II, ” Naples, Itraly, in 1990.
His field of research is in analysis and grounding
of power systems. He is currently the Assistant
Electrical Department Head at Chu & Gassman,
New York. He has authored many journal papers,
and the textbook Electrical Safety of Low-Voltage
Systems.
Dr. Mitolo is very active within the IEEE IAS In-
dustrial & Commercial Power Systems Department,
where he currently is the Chair of the Power Systems Engineering (PSE) Com-
mittee, the Chair of the Power Systems Analysis Subcommittee, and the Chair
of the Power Systems Grounding Subcommittee. He is also an Associate Editor
of the PSE and ES Scholarone Manuscript. He is also the recipient of the Lu-
cani Insigni Award in 2009, for merits achieved in the scientific field. He is a
registered Professional Engineer in Italy.
