This document discusses lightning arresters, including their purpose, types, classification, ratings, and service conditions. It describes three main types of arresters - expulsion, valve, and gapless metal-oxide. Arresters are classified into four classes based on their application and ratings. Standard ratings include nominal discharge current and voltage. Normal service conditions include temperature, radiation, altitude, and frequency ranges, while abnormal conditions require special consideration.

2. Summary
 What is Lightning Arrester.
 Types of Lighting Arrester.
a- Expulsion type
b- Valve type arrester
c- Gapless metal-oxide type
 Classification of Lighting Arrester
a- Station class
b- Intermediate class
c- Distribution class
d- Secondary class
 Identification
 Standard Ratings
 Service Condition
a- Normal Service Condition
b- Abnormal Service Condition

3. What is Lightning Arrester
 Lighting Arrester:- A
device designed to protect
electrical equipment from
high transient voltage and to
limit the duration and
frequency the amplitude of
follow-current.
 Surge arrester are usually
connected the electrical
conductors of a network and
earth though they may

4. Types of Lighting Arrester
Originally, three types of surge
arresters. They are:
1. Expulsion type;
2. Valve type arrester;
3. Gapless metal-oxide type;
Ref-http://www.geindustrial.com/Newsletter/lightning_arresters_guide.pdf

5. Expulsion type
 This type of arrester is also
called ‘protector tube’ and is
commonly used on system
operating at voltages up to
33kV. It essentially consists of
a rod gap AA’ in series with the
protector tube. The upper
electrode of protector tube is
connected to rod gap and the
lower electrode to the earth.
http://www.circuitmaniac.com/2009/03/21/expulsion-type-arrester/

6. Valve Type Arrester
 Valve type
arresters incorporate non
linear resistors and are
extensively used on
systems, operating at high
voltages. It consists of two
assemblies (i) series spark
gaps and (ii) non-linear
resistor discs in series. The
non-linear elements are
connected in series with the

7. Gapless metal-oxide type
 The gapless metal-oxide type
arrester are the most widely used today.
The metal oxide lightning arrester is the
most advanced over-voltage protector. It
is widely used as protective devices
against switching and lightning over
voltages in power electrical systems such
as power transformers
,distributors, generators, compensation
capacitors.

8. Classification of Lighting Arrester
 There are four classifications of surge
arresters.
i. Station class
ii. Intermediate class
iii. Distribution class(heavy, normal and
light duty)
iv. Secondary class
 The station class surge arrester is the
best because of its cost and overall
protective quality and durability. It has

9.  Nominal discharge current-Peak
value of lightning current impulse
which is used to classify an arrester.
 Surge arrester are classified by their
nominal discharge current.
 Station class for 10,000A arresters;
 Intermediate(Series A) for 5,000A
arrester
 Distribution(Series B) for 5,000A
arrester
IS 15086-44-SURGE ARRESTER(Part-1),clause 3.1

10. Identification
 Surge arrester shall be identified by the
following minimum information which
shall appear on the rating
plate(nameplate):
1- Rated Voltage;
2- Rated Frequency
3- Nominal Discharge Current(Specifying
for the 5 000A arrester whether series A
or B, and for the 10 000 A
arrester, whether light or heavy duty)
4- Long-duration discharge class(for 10
000 A heavy duty arrester)
5- Manufacturers name or trademark, type

11. Standard Ratings
 Standard values of rated voltages for
arresters(kV r.m.s.)are specified in
table 2 in equal voltage steps within
specified voltage ranges.
• Standard rated frequencies are 50Hz
and 60Hz
IEC-60099-44_Surge arrester, clause 5.1&2

12. Service Condition
1- Normal service conditions:- Surge
arresters which conform to this standard
shall be suitable for normal operation
under the following normal service
condition;
a- Ambient air temperature within the
ranges of -40 C to +40 C;
b- Solar radiation;
c- Altitude not exceeding 1000m;
d- Frequency of the A.C. power supply not
less than 48 Hz and not exceeding 62 Hz.
e- Wind speed ≤ 34 m/s

13. 2- Abnormal service conditions:-
Surge arrester subjected to other than normal
application or service conditions may required
special consideration in design, manufacture or
application. The use of this standard in case of
abnormal service conditions is subjected to
agreement between the manufacture and the
purchaser. A list of possible abnormal service
condition is given.
 Temperature in excess of +40 C or below -40
C.
 Altitude higher than 1000 m.
 Nominal system frequency below 48Hz or
above 62Hz.
 Unusual transportation or storage.