Lightning Arresters
P30027 – 18 KVA
P30038 – 10 KVA
Description & Installation
Printed in USA – 09/11
TO330 Rev. B
Table of Contents
Page
1.0
SCOPE
2
2.0
PRODUCT OVERVIEW
2.1 Intended Uses
2.2 Lightning Arresters 18KVA, 10KVA
2.3 5 kV Spark Gap
2
2
2
2
3.0
PRODUCT FEATURES
2
4.0
INSTALLATION
2
4.1 Mounting Lightning Arrester
4.2 Station Ground Connection
4.3 Remote Ground Connection
General Information
3
3
3
4
PHYSICAL CHARACTERISTICS
5.1 Mechanical Configuration
5.2 Environmental Requirements
5
5
5
5.0
Page 1
1.0
Scope
This document describes the technical specifications, technical requirements
and installation instructions for the P30027 and P30038 SNC Lyte Lynx®
Lightning Arrester packages. It provides an understanding of the basic functions
and features available with these units.
2.0
Product Overview
2.1 Intended Uses
The purpose of the lightning arrester is to protect the metallic shield of the
CO/Remote cable and the isolation devices during lightning or fault conditions.
When the voltage reaches the level of the arrester’s discharge rating, the
voltage will find a path to station ground rather than damaging the cable or
isolation devices.
2.2 18kV and 10kV Lightning Arresters
SNC offers two models of Lyte Lynx® Lightning Arresters. Since Lyte Lynx®
carries a continuous rating of 20kV, 60HZ, RMS as well as a 65kV impulse peak
voltage, the 18kV model (P30027) is normally recommended. However, for
installation where the dielectric condition of the incoming CO/Remote cable is
questionable, the 10kV model (P30038) may be desired since GPR voltages
rarely exceed 10kV, 60Hz, RMS maximum.
2.3 5kV Spark Gap
This feature allows termination of cable pairs for isolation transformer center
tap drainage to provide protection for Class A service pairs whenever the
lightning/surge arrester discharges.
3.0
Product Features
The P30027 and P30038 use a non-shattering, polymer lightning arrester
installed in an insulated housing. Each has a continuous kV arrester rating with
a discharge voltage rating substantially lower than the tested 65 kV BIL of the
Lyte Lynx® system. During a lightning strike, the voltage potential difference
between the CO/Remote cable shield and station ground is limited to the
breakdown or discharge voltage of the arrester so that both the entrance cable
and isolation equipment are protected.
Mounted inside a fiberglass enclosure with a clear plastic protective cover, the
arrester is normally installed near the CO/Remote cable entrance into the Lyte
Lynx® card shelf – typically either directly below or alongside the shelf.
4.0
Installation
CAUTION: To provide personnel isolation from local ground, stand on a
thick rubber mat and use other adequate insulation devices (rubber gloves)
when working on the Lyte Lynx® system.
Page 2
CAUTION: The incoming telephone pair(s) should be contained in insulated
conduit (PVC, etc.), or the pair(s) should be jacketed with sufficient
insulation to withstand a voltage rise from ground fault potential and from
fault induction voltage.
CAUTION: Any metallic shielding on the incoming CO/Remote pair(s) must
be isolated from substation grounds all the way from the network low
voltage interface (300 volt peak GPR point per IEEE Standard 487) to the
entry into the Lyte Lynx®. The conductors must also be isolated.
4.1
Mounting Lightning Arrester
Drill holes in the back of the Lightning Arrester enclosure and securely mount
to a non-metallic wall or backboard (use the backboard that the Lyte Lynx®
card cage is mounted to if backboard is large enough). Depending upon the
space available, this can be to the left (looking at the front of the card cage)
or just below the card cage. The Lightning Arrester may be mounted upside
down to fit the situation. See Figure 1 for an example of how the lightning
arrester is installed.
4.2
Station Ground Connection
Connect a #6 AWG wire from the bus bar connector lug at the bottom of the
arrester enclosure to station ground. Keep this wire as short as possible. See
Figures 1 and 3.
4.3
Remote Ground Connection
At the point where the cable would be centered in the Lightning Arrester
enclosure, carefully strip off 4 to 6 inches of the cable jacket to reveal the
cable shield. Open the cable shield by removing the center 2 or 3 inches of the
exposed metallic cable shield. Try to do this without disturbing the cable pairs.
Slip the cable through the PVC fittings on each side of the upper part of the
enclosure. Holes in the PVC fittings allow the use of tie wraps (included) to
secure the cable to the enclosure.
Connect the wire attached to one end of the arrester to the CO side of the
cable shield with a cable shield “Bullit” Bond (provided). Keep this wire from
the cable shield to the arrester as short as possible – avoid a large loop.
Connect the wire attached to the 5kV spark gap to the station side of the cable
shield - or with a separate wire - connect it directly from the spark gap to the
ground terminal of the card shelf. See Figure 1.
Page 3
General Information
The above installation scheme meets the recommended protection practice of IEEE
Standard 487-2000 - remote ground outside the GPR zone of influence (300 volt GPR
location) is accessible via a 5 kV spark gap located in the lightning surge arrester
housing external to the card shelf.
This installation scheme also provides for coordinated 65 kV BIL protection of both the
isolation equipment (shelf and cards) and the dedicated entrance cable. The 5 kV gap
coordinates drainage of surge voltage difference between the dedicated cable pairs
and the shield should the power type surge arrester operate and equalize ground
potential difference between station ground and remote ground via the cable shield.
The isolation system is designed around the protection practice of IEEE Standard 4871992. It is recommended that this configuration be used in any application
environment where surges are possible. The BIL of the isolation system is assured and
the dedicated cable receives similar BIL protection and insulation protection
coordination between shield and cable conductors.
Note: In some applications “remote ground” is directly needed for a circuit function
such as for PBX ground start trunks (a less desirable trunk seizure configuration that is
more prone to possible transient voltage and circuit noise problems than a loop start
trunk). When a direct “remote ground” connection is required, a protection system
application utilizing the 5kV spark gap must have the gap bypassed by one of the pairs
to get central office ground directly accessible to the PBX card. This effectively
disables the 5kV spark gap.
Figure 2:
10KVA
Lightning
Arrester
P30038
Page 4
Connect to Card
Shelf Remote
Ground
Connect to CO
Cable Shield
Connect Station Ground to This Ground Lug
Figure 3: Lightning Arrester Connections
5.0
Physical Characteristics
5.1 Mechanical Configuration
Table 1: Physical Dimensions
PART NUMBER
HEIGHT
WIDTH
DEPTH
P30027
14.20”
(36 cm)
21.25”
(54 cm)
7.10”
(18 cm)
P30038
11.00”
(28 cm)
15.00”
(38 cm)
5.30”
(13.5 cm)
5.2 Environmental Requirements
The Lyte Lynx® Lightning Arrester system may be installed in an indoor or
moderate outdoor environment and is guaranteed operable in temperatures
ranging from –40ºC to 100ºC (–40ºF to 212ºF) and under humidity conditions
from 0–99% – relative humidity non-condensing.
Page 5
For further information or for technical support – call 800-558-3325
or visit www.sncmfg.com
SNC Manufacturing Co., Inc.
101 West Waukau Ave., Oshkosh, WI 54902-7299
800-558-3325 or 920-231-7370 FAX 920-231-1090
E-mail: telecom@sncmfg.com
Website: www.sncmfg.com
Page 6
TO330 Rev. B - 09/11