Hélita:a pioneer company in lighting protection
Market leader on lighting protection since 1932, Hélita immediately made its marks as an innovator with the invention of the first early streamer emission lightning conductor.
HELITA: a world market leader
Active growth
Hélita's professionalism and the reliability of its products make it a
well known, highly respected company. It is the world's manufacturer of early
streamer emission lightning conductors, and sales are increasing annually by an
average of 10 to 15%.
A dynamic export policy
Hélita has established offices in over 60 countries since its creation,
and 50% of its turnover now comes from overseas.
Today, over 230.000 Hélita lightning conductors protect its clients against
lightning in France and throughout the world.
The lightning protection specialist
The experience Hélita gained in the lightning conductors sector meant that it could quickly develop wide-ranging expertise. From early streamer emission lightning conductors through earth plates and surge arresters to meshed cages, Hélita now offers a complete range of products and services, which meet the respective standards and requirements of the different countries in which its expertise has been recognized. Over 8% of turnover dedicated to research. The study of lightning and new protective methods are a constant preoccupation for Hélita. The company carries out research in its laboratories at Bagnères de Bigorre and also in the field both in France and overseas.
The lightning conductors, a key product: the PULSAR
In 1982, Hélita joined with the University of Haute Alsace and
other educational institutions to invent a new generation of lightning
conductors: the electric ionizing lightning conductor. In 1984, a research
project carried out in conjunction with the CNRS Laboratoire Physique de
Décharges (plasma research laboratory) led to another world first: the PULSAR (CNRS/Hélita
patent pending in France and worldwide), the first in a new generation of early
streamer emission lightning conductors. This conductor, which has been used as a
reference ever since, underwent effectiveness tests during its development which
are now required standard NF C 17-102.
1 Direct
strike –on the building
2 Indirect strike –on an
aerial electric line
3 Indirect strike –through
the earthing network
PULSAR, THE HIGH PULSE VOLTAGE E.S.E. LIGHTNING conductor
OPERATING PRINCIPLE
When the lightning approaches the ground, a luminous ascending brush discharge
is initiated at the lightning conductor. In the case of a Franklin rod, this
ascending brush discharge propagates in the direction of the descending leader
after a long transition phase. The Pulsar initiation advance permits to reduce
the required time for the formation and continuous propagation of the ascending
discharge and brings thus a higher efficiency for the lightning capture than a
Franklin rod tip.
AN EFFICIENT INITIATION ADVANCE
Thanks to its initiation advance, the Pulsar emits a high voltage signal at
clearly determined and controlled frequency and amplitude. Its effectiveness is
guaranteed by the rapid formation and propagation of the upward leader, while
reducing the development of space charges around the point.
ENERGY AUTONOMY
The Pulsar is also self-contained. It draws its energy from the ambient electric
field existing at the time of the storm (10 to 20 kV/m). The initiation advance
starts up as soon as the ambient field exceeds a peak value which corresponds to
the minimum lightning stroke risk.
The Pulsar tip plays a triple role:
Collect the energy necessary to power the electrical device contained in the cylinder,
Emit the brush discharges created by the high-voltage pulses,
Capture the lightning current to convey it to the ground.
The metal disc is the upper part of the external air gap
designed to convey the lightning current from the tip to the ground. The metal
cylinder contains the electric device of the Pulsar system that generates the
brush discharges.
The pole serves to fix the Pulsar for installation. The connecting clamp must be
fixed to it, together with the down conductor.
Tip 75 cm long and 18 mm diameter
Metal disc with variable diameter and thickness for the different Pulsar models.
Metal cylinder containing the early streamer emission device.
Pulsar pole outside diameter 30 mm.
Connecting clamp to fix the down conductor.
EFFICIENCY MEASUREMENT PRINCIPLE
The collaboration between Hélita and CNRS also gave birth to a method of test in high voltage laboratory, used as a procedure of evaluation of the Early Streamer Emission air terminals in Appendix C of standard NF C 17-102. The aim of this test procedure is to evaluate the efficiency of an Early Streamer Emission air terminal.
Manufacturing Tests
Each Pulsar unit leaving our workshop undergoes a series of high voltage tests to confirm that the internal insulation voltage is higher than the breakdown voltage of the external air gap of the lightning conductor. All the Hélita production is tested using this method. At the end of the manufacturing process, all Pulsar units undergo a test to check that the lightning discharges will effectively flow to earth. These tests are conducted in the Bagnères-de-Bigorre high voltage laboratory.
Before delivery, the Pulsar units
undergo a further test to check that the characteristics of the high voltage
signal - frequency of repetition and amplitude - correspond with Hélita
specifications.
Installation and verification
The installation and verification of
lightning protection systems using one or several Pulsar units must meet the
requirements of NF C17-102 and the manufacturer's recommendations.
Certifications
High voltage Institute Certification -CEB (Bazet, France)
British Standard Institute-BSI (Great Britain)
Wuhan High Voltage Research Institute (China)
High Voltage Institute I.R.E.Q (Canada)
Korean Electrotechnology Research Institute-KERI (Korea)
Central Laboratory for Electrical Industries-LCIE (France)
For more information, please contact us.
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