The purpose of NF C17-200 is to define the conditions under which the installations concerned must be established and maintained to ensure the safety of people, the preservation of property and, when they are
powered by a public distribution network, to avoid any disruption in the overall operation of this network.
The rules apply to outdoor electrical installations:
Equipment with main insulation, in which
different accessible conductive parts
are interconnected to an earth terminal.
Requires the use of a protection system
preventing indirect contacts.
Equipment built in such a way as to render
any fault between the energized parts
and accessible parts improbable (double
insulation or reinforced insulation). Provides
its own safety, does not require an earth
terminal and requires no protective system
against indirect contacts.
Electrical equipment where protection is
based on extremely low voltage SELV power
(< 50VAC or < 120VDC) and which are not
generated voltages higher than the upper
limit of Domain I.
Class III equipment must not contain
earthing terminals.
The grounds of each light source are connected to an earth point. The system is
protected against indirect contact by means of a Residual Current Device (RCD).
NF C17-200 recommends (compulsory in
AQ3: very stormy) conductive lampposts to be earthed with a 25mm bare copper conductor acting both as earth and equipotential link between the different
lampposts.
Otherwise, and outside AQ3 areas, the grounding employs one or more unremovably interconnected earth electrodes (the lamp
posts are linked each other and to the ground terminal by an insulated protective
conductor).
TT systems are protected against indirect currents by one or more RCDs.
Using an Automatic Disconnection Device
(ADD, Idil) for each light source ensures all lampposts remain lit in the event of an earthing fault on one of the lights and
automatic re-arming of the latter in the event of a temporary fault.
On Class I lamps, NF C17-200 recommends the use of an ADD (Idil) in each lamppost; failing this, an RCD can be used, but
without automatic rearming.
The grounds of each light source are connected to neutral. The TN-C diagram combines protection and neutral on a single conductor (PEN). The TN-S system has a protective conductor (PE) separate from the neutral. TN systems are protected against fault currents by a circuit-breaker or cut-out. And it is possible, in the TN-S diagram, to use an Automatic Disconnection Device (ADD) at each light source to ensure continuity of lighting.
Cable ducts and sealing/insulation sleeves:
Outside, it is necessary to reconstitute cable-end seals with sealing sleeves.
Inside lampposts, it is recommended to maintain double insulation as far as the inside of the Class II junction box and to
reconstitute cable-end seals with sealing sleeves.
Street furniture and aedicules:
Must be protected by a Residual Current Device (RCD-30mA) integrated into the equipment.