Datasheet

Specifications are subject to change without notice. Copyright 2011 Eaton Industries Pty Ltd
Technical Specification –ESF series surge filters
Tvss Doc# 510ESF
Page 3 of 6
GUIDELINES FOR PLANNING YOUR SURGE
PROTECTION
We recommend that the specifier and installer
become familiar the standards applicable to the
equipment and site, prior to any final product
selection and placement. Correct product selection
according to risk and location category is essential to
a successful solution. This may also involve changing
some aspects of existing electrical infrastructure to
ensure an effective result.
• Pay particular attention to the positioning of
any SPD in relation to the M.E.N. point or
other effective earth termination position.
• It is imperative that input and output circuits
be separated from each other to ensure that
coupling of surges across cables does not
occur. If this cannot be achieved, the use of
shunt-only (single-port) SPD’s should be
considered.
• If applicable, ensure that appropriate
approvals to connect are observed with your
local energy authority.
• The output of any series SPD does not
automatically confer a reclassification of the
load side circuit category rating. This is due
to the common neutral and earth shunt
circuits. If sensitive, low power devices (i.e.
ANSI/IEEEC62.41 Category A) are to be
connected to the unit’s output, we
recommend investigating the fitting of further
downstream SPDs at the sensitive
equipment distribution board.
Further information on surge protection guidelines
may be obtained through your local standards office.
If in doubt, please contact your distributor.
INSTALLATION GUIDELINES
This Surge Protection Device (SPD), is intended to
be installed and operated in accordance with the
manufacturers instructions. Installation instructions
are provided with the unit and should be read and
understood prior to attempting the installation.
To make any SPD effective, there are a few simple
principles that need to be considered:
CABLE LENGTHS AND SIZES
Under surge conditions, all cables exhibit voltage
drop. For example, a 15kA surge current, depending
on size and length of cable, can result in a voltage
drop in excess of 2000v per metre. If this occurs in
neutral or earth conductors, then the filter element
would provide little protection. It is therefore
important to install the SPD device as close as
possible to the point of entry to the facility. Keep
neutral and earth cables as short as possible, using
the largest possible diameter cable practical. Wiring
regulations can often stipulate much smaller cable
sizes for earth and neutral, however, in surge
applications the opposite is true. Using earth and
neutral cables with the same cross-sectional area
and size as the phase cables is more appropriate.
The better solution is to use 2 identical conductors in
parallel for all primary cabling, each ½ of the area
(i.e. instead of a 50mm
2
cable, use 2x 25mm
2
in
parallel). This reduces the inductance of the cable
run, reducing voltage drop under surge conditions.
Cabling on the load side of the filter can be of
conventional design and layout.
For TT applications, consider fitting small busbars
(25 x 3mm) for earth connection from the SPD
Primary earth to the earthing point. In TNC-S
applications, consider using a busbar (insulated) as a
neutral conductor back to the M.E.N. point. Flexible
busbars are easy to form and install.
The unit may be inverted for bottom-entry/top exit if
desired.