ERICO TSG User Manual

CRITEC®TSG SERIES
INSTALLATION AND

OPERATING INSTRUCTIONS

Surge Reduction Filters (TSG-SRF)

Warnings

• TSG-SRFs must be installed in accordance

HAZARDOUS VOLTAGES EXIST
WITHIN THE TSG-SRF ENCLOSURE.
THIS UNIT SHOULD BE INSTALLED
AND SERVICED ONLY BY QUALIFIED
PERSONNEL AND IN ACCORDANCE
WITH RELEVANT NATIONAL
ELECTRICAL AND SAFETY CODES.

ALL INSTRUCTIONS MUST BE
FOLLOWED TO ENSURE CORRECT
AND SAFE OPERATION OF THE SRF.

2. WARNINGS

• PRIOR TO INSTALLATION. Ensure that the
TSG-SRF is of the correct voltage, current,
phasing, and frequency, and is of the type
recommended by the manufacturer for the
equipment and power distribution system
in use.

• DO NOT MEGGER. This unit contains
over-voltage protection components.

• TSG-SRFs contain capacitors. Disconnect
power at least 1 minute prior to removing
the escutcheon panel. Check voltage prior
to working on SRF internals.

•

TSG-SRFs must be connected to a low

impedance earth (<10Ω) for correct operation.

WARNING
ERICO products shall be installed and used only as indicated in ERICO’s product instruction sheets and training materials. Instruction sheets
are available at www.erico.com and from your ERICO customer service representative. Improper installation, misuse, misapplication or
other failure to completely follow ERICO’s instructions and warnings may cause product malfunction, property damage, serious bodily
injury and death.

WARRANTY
ERICO products are warranted to be free from defects in material and workmanship at the time of shipment. NO OTHER WARRANTY,
WHETHER EXPRESS OR IMPLIED (INCLUDING ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE), SHALL
EXIST IN CONNECTION WITH THE SALE OR USE OF ANY ERICO PRODUCTS. Claims for errors, shortages, defects or nonconformities ascer­tainable upon inspection must be made in writing within 5 days after Buyer's receipt of products. All other claims must be made in writing
to ERICO within 6 months from the date of shipment or transport. Products claimed to be nonconforming or defective must, upon ERICO's
prior written approval in accordance with its standard terms and procedures governing returns, promptly be returned to ERICO for inspec­tion. Claims not made as provided above and within the applicable time period will be barred. ERICO shall in no event be responsible if the
products have not been stored or used in accordance with its specifications and recommended procedures. ERICO will, at its option, either
repair or replace nonconforming or defective products for which it is responsible or return the purchase price to the Buyer. THE FOREGO­ING STATES BUYER’S EXCLUSIVE REMEDY FOR ANY BREACH OF ERICO WARRANTY AND FOR ANY CLAIM, WHETHER SOUNDING IN CON­TRACT, TORT OR NEGLIGENCE, FOR LOSS OR INJURY CAUSED BY THE SALE OR USE OF ANY PRODUCT.

LIMITATION OF LIABILITY
ERICO excludes all liability except such liability that is directly attributable to the willful or gross negligence of ERICO's employees. Should
ERICO be held liable its liability shall in no event exceed the total purchase price under the contract. ERICO SHALL IN NO EVENT BE
RESPONSIBLE FOR ANY LOSS OF BUSINESS OR PROFITS, DOWNTIME OR DELAY, LABOR, REPAIR OR MATERIAL COSTS OR ANY SIMILAR OR
DISSIMILAR CONSEQUENTIAL LOSS OR DAMAGE INCURRED BY BUYER.

with ALL relevant national electrical and
safety codes.

• The power supply to the TSG-SRF should
always be turned off (and locked) before the
escutcheon panel is removed for any purpose.
Internal circuit breakers do not fully isolate
the filter.

• Check all TSG-SRF terminals for tight
connections. (Some terminals may become
loose during transport)

• Ensure all input and output cabling, once
installed, is tightened to the correct torque
settings (see Table 3, Page 16).

• Do not disconnect upstream Earth or Neutral
connections supplying the SRF while power
is still applied, as this may damage the SRF
or load.

• No combustible items should be stored
within the SRF during operation.

• Do not leave this manual behind the
escutcheon panel after applying power to the
SRF. Retain this manual for future reference.

• Failure to heed instructions or warnings may
result in personnel injury, equipment damage
or ineffective transient protection.

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Contents

TABLE OF CONTENTS

1. Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Page 2

2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 4

3. Installation Cautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Page 6

4. Identify the Distribution System . . . . . . . . . . . . . . . . . . . . . . .Page 8

5. Mounting the Surge Reduction Filter ( SRF ) . . . . . . . . . . . . .Page 12

6. Optimising Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . .Page 13

6.1. Fusing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Page 13

6.2. Cabling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Page 14

6.3. Output Distribution . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Page 17

6.4. Earthing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 18

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6.5. Connection of Alarm Circuits . . . . . . . . . . . . . . . . . . . . . .Page 19

6.6. Installation Arrangement for Australian MEN Systems . . .Page 20

6.7. TSG-SRFs on Sub-Circuits . . . . . . . . . . . . . . . . . . . . . . . . .Page 21

7. Servicing & Trouble Shooting . . . . . . . . . . . . . . . . . . . . . . . .Page 23

8. Non-Standard Products & Accessories . . . . . . . . . . . . . . . . . .Page 24

9. Schematic Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Page 25

10. Physical Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Page 26

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Introduction

1. INTRODUCTION

The CRITEC®Triggered Spark Gap Surge
Reduction Filter (TSG-SRF) from ERICO
rates high energy clamping devices and special
filtering circuitry. TSG-SRFs are installed in series
with the circuit, usually at the point of entry to
the building or structure. They are available in
single or three-phase configurations for load
currents from 40A to 2000A per phase.

The purpose of a TSG-SRF is to filter and
protect against lightning induced transients.
The SRF provides a clean, filtered supply of
electricity to all output connected equipment
when installed in accordance with the
manufacturer’s instructions.

Protection is achieved via a three-stage circuit.
This includes the internal CRITEC Triggered
Spark Gap unit as the primary surge diverter,
a purpose designed low pass filter network

®

incorpo-

and a secondary, Transient Discriminating (TD)
diversion stage to further clamp the transient
energy to safe levels. This allows the TSG-SRF
to:

• Provide filtering to the clamped waveform
in order to reduce the rate of voltage rise.

• Provide a secondary stage of surge diver­sion to protect equipment from transients
which may be induced onto the SRF out
put cables or be caused by the load itself.

The use of this combination of technologies
has resulted from considerable advances in
technology which have negated previous
disadvantages associated with spark gaps.

The use of spark gaps has not been practical
in the past due to the high initiation voltages
required to activate such devices and also
their poor follow-current performance.

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Introduction

Both issues have been addressed with the

®

CRITEC

TSG, a spark gap surge diverter
incorporating a triggering device which
enables the TSG to operate on much lower
voltages than was previously possible.
Additionally, the TSG is able to extinguish the
spark and return to the peak mains voltage
as soon as the transient event has passed,
thereby greatly improving follow-current
performance.

These considerable technological advances
mean that the TSG can be utilised as the
primary shunt diverter within the new SRF,
exploiting the performance benefits of spark
gap diverters.

Incorporating TSG technology into a surge
reduction filter has allowed a fundamental
breakthrough in the overall design of the
filter. Ferrite cored inductors, which are
much smaller than non-saturating air-cored
inductors required in MOV based surge
reduction filters have been used in the
CRITEC SRF.

The combination of TSG and TD technology
provides the benefits of high surge capability,
low let through voltage and considerably
reduced dv/dt. This applies to both surge
performance and over-voltage withstand from
short and long duration high-energy surges.

TD technology has been developed
specifically for abnormal over-voltage
conditions that may occur on sites with
poor voltage regulation, or due to wiring or
distribution faults. TD and TSG technologies
feature an extremely high over-voltage
withstand. This eliminates heat build up that
can occur with standard technologies when
the protection devices start to clamp on the
peak of each abnormal mains cycle.

Traditional MOV technology is not suitable in
applications where sustained over-voltage
conditions can be experienced. The range of
CRITEC TSG-SRFs, with a higher abnormal
over-voltage withstand, are preferred in these
environments.

The use of ferrite-cored inductors is possible
because the let-through voltage from a TSG
remains high for only a few microseconds
(μs). In comparison, the let-through voltage
from a MOV based device remains at
anywhere between 600V and 1000V for the
duration of the surge. This time can range
from 30μs to 400μs and above for longer
tail pulses and determines how much energy
the inductor has to store before reaching
saturation and becoming ineffective.

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Installation Cautions

3. INSTALLATION CAUTIONS

CAUTIONS:

• Transient protection devices are usually
rated to protect against non-repetitive
pulses from sources such as direct or
induced lightning energy.

• They are not designed to provide
protection against repeated cyclic
anomalies such as those caused by
motor speed control notching (variable
speed controls, etc.).

• SRFs are not designed to provide
protection against sustained over-voltage
conditions where the supply voltage
exceeds, for an extended period of time,
the nominal rating of the protection
equipment (continuous over-voltages

from poorly regulated generators or
distribution systems, for example).

• Smaller power generation equipment does
not always conform to the same standards
of voltage regulation that is in place for
mains power reticulation. A large number
of smaller or cheaper generators have a
voltage waveform that approximates
240Vrms (often poorly regulated), but
more importantly, which often contains
significant higher order harmonics and
may exhibit a peak voltage on each
half cycle far in excess of the normal
340V (peak). Such machines are usually
capacitive excitation induction generators,
as opposed to synchronous generators.
The problem is usually increased when
the generator is lightly loaded.

Figure 1. Seek specialist advice with the above installations.

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Installation Cautions

• Harmonic voltages may also be present in
distribution systems that do not feature
generators. This is normally where non­linear loads are used, such as UPSs, recti­fiers, switch-mode power supplies and
motor speed controls. The harmonic volt­ages may have peak voltages in excess of
the protective clamping voltages, causing
problems such as excessive heat build up.
Because the harmonic waveforms contain
higher order frequencies, capacitive leak­age currents may increase to above
prescribed limits and shorten the life of
the SRF. It should be noted that in sites
with large harmonic voltage distortion, the
SRF capacitance may dramatically affect
the power factor.

• Seek the manufacturer’s advice before
installing any SRF into a circuit which
features a total harmonic voltage ratio
above 5%.

• With large transients, significant energy
may be passed by the SRF diverters back
to the source or to earth. This may, under
some circumstances, cause upstream earth
leakage circuit breakers or residual current
devices (ELCBs & RCDs) to nuisance trip.
Where possible, these devices should be
installed after the SRF in order to reduce
this possibility.

By-pass switches are not recommended

•

to be used with SRFs

the protection offered. The connection of
the by-pass switch compromises the input
to output separation requirement by
bringing the SRF input and output wiring
into close proximity at the switch. Due
to the high reliability of the SRF and,
provided that spare fuses are on hand (for
SRFs of 125A and larger), it is deemed to
be unnecessary to provide a means by
which to bypass the SRF. If these situations
cannot be avoided, contact your local

®

office to assess the possibility of a

ERICO
special design.

as they compromise

• Transient protection devices often have
minimum requirements for upstream
fusing to ensure proper operation. See
Section 6.1 for fusing requirements.

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Identify the Distribution System

4. IDENTIFY THE DISTRIBUTION
SYSTEM

A number of different power distribution
systems are employed in various countries
around the world. It is important to identify
the distribution system in use prior to installa­tion of the SRF, and confirm that the SRF is
the model recommended by the manufactur­er for that distribution system.

To identify the distribution system in use,
consult reputable and knowledgeable sources
such as:

• The local power supply authority

• Local electrical engineers

• Applicable regulatory bodies or standards

associations

Alternatively, confirm the type of distribution
system used by personal inspection. By visual­ly tracing the neutral and earthing conductors
from the load equipment or sub-distribution
point back to the point of entry (and perhaps
to the supply transformer), the type of distri­bution system should be identifiable with the
aid of the following diagrams (Figures 2-6).

These are prescribed in local regulations and
describe the relationship between the source,
exposed or conductive parts of the installa­tion and earth. Amongst these, the TN-C,
TN-S, TN-C-S and TT systems are most
commonly encountered. Note that supplies
such as those used in industry and mining
may often use a different distribution system
to that of the local supply authority.

Figure 2. TN-C system: In this system, the neutral and protective earth conductor combine in a single
conductor throughout. All exposed conductive parts are connected to the PEN conductor.

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Identify the Distribution System

* *

Figure 3. TN-S system: In this system, a separate neutral and protective earth conductor are run
throughout. The protective PE conductor can be the metallic sheath of the power distribution cable or a
separate conductor. All exposed conductive parts of the installation are connected to this PE conductor.

Figure 4. TN-C-S system: In this system, a separate neutral and protective earth functions combine in a
single PEN conductor. This system is also known as a Multiple Earthed (MEN) system and the protective
conductor is referred to as the combined neutral earth (CNE) conductor. The supply PEN conductor is
earthed at a number of points throughout the network and generally as close to the consumer’s point
of entry as possible. All exposed conductive parts are connected to the CNE conductor.

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