Installation Manual

Installation, Operation and Maintenance Manual IO-70103 Rev 2, 1/2015
An insulated grounding conductor is required
in addition to any metallic raceway, which may
be used as a grounding conductor. For
parallel-connected SPDs, the grounding
conductor should be the same wire size as
the associated power conductors.
UNGROUNDED
POWER SYSTEMS
ARE INHERENTLY UNSTABLE AND CAN
PRODUCE EXCESSIVELY HIGH LINE-TO-
GROUND VOLTAGES DURING CERTAIN
FAULT CONDITIONS. DURING THESE FAULT
CONDITIONS ANY ELECTRICAL EQUIPMENT,
INCLUDING AN SPD, MAY BE SUBJECTED TO
VOLTAGES WHICH EXCEED THEIR
DESIGNED RATINGS. THIS INFORMATION IS
BEING PROVIDED TO THE USER SO THAT AN
INFORMED DECISION CAN BE MADE BEFORE
INSTALLING ANY ELECTRICAL EQUIPMENT
ON AN UNGROUNDED POWER SYSTEM.
CONTACT FACTORY FOR UNGROUNDED
APPLICATIONS.
ATTENTION – LES SYSTÈMES
D’ALIMENTATION NON-MISES À LA TERRE
SONT INTRINSÈQUEMENT INSTABLES ET
PEUVENT PRODUIRE DES TENSIONS DE
PHASE TRÈS ÉLEVÉES AU COURS DE
CERTAINES CONDITIONS DE DÉFAUT.
PENDANT CES CONDITIONS DE DÉFAUT
TOUT ÉQUIPEMENT ÉLECTRIQUE, Y
COMPRIS UN SPD (PROTECTEUR DE
SURTENSION), PEUT ETRE SOUMIS A DES
TENSIONS SUPERIEURES À LEURS VALEURS
STANDARDS. CETTE INFORMATION EST
FOURNIE À L’UTILISATEUR AFIN QU’UNE
DÉCISION CORRECTE PEUT ÊTRE PRISE
AVANT D’INSTALLER UN ÉQUIPEMENT
ÉLECTRIQUE SUPPLIMENTAIRE SUR UN
SYSTÈME D’ALIMENTATION NON-MISE À LA
TERRE. CONTACTER L’USINE POUR LES
APPLICATIONS NON-MISES À LA TERRE.
Grounding conductors must be routed with
the associated power conductors in the same
raceway (conduit). When metallic raceways
are used, adequate electrical continuity must
be maintained at all raceway connections,
particularly raceway terminations to the
electrical enclosures.
The use of isolating bushings or other means
to interrupt a metallic conduit run is a
potential safety hazard and is not recommended.
Grounding Electrode — Surge protective
devices do not discharge all surges to ground
(earth). Surge protective devices can also
divert the surge current back to its source to
complete the electrical circuit.
In the case of lightning whose potential is
developed with respect to the earth, the
SPD diverts the surge current to the
grounding electrode (earth connection).
However, for most transient surges that are
developed by switching loads, the SPD diverts
the surge current back to its source without
involving the grounding electrode.
For proper SPD performance, the service
entrance grounding electrode system must
comply with the NEC by having all available
electrodes (building steel, metal water pipe,
driven rods, concrete encased electrodes,
etc.) properly bonded together and
connected to the power system grounding.
The use of a separate grounding electrode to
ground the SPD defeats the effectiveness of
the SPD, is a potential safety hazard, may
cause equipment damage, is an NEC violation
(reference NEC 250-51 and 250-54), and is
not recommended.
Neutral Connection —
NOTICE - FOR PROPER AND SAFE OPERATION,
THE SPD’s NEUTRAL MUST BE RELIABLY
CONNECTED TO THE NEUTRAL OF THE
SOURCE. FAILURE TO PROVIDE A RELIABLE
NEUTRAL CONNECTION MAY RESULT IN
FAILURE!
Parallel Connection / Wire Diagram —
6