IEC 60099-4:2004/AMD2:2009
(Amendment)Amendment 2 - Surge arresters - Part 4: Metal-oxide surge arresters without gaps for a.c. systems
Amendment 2 - Surge arresters - Part 4: Metal-oxide surge arresters without gaps for a.c. systems
Amendement 2 - Parafoudres - Partie 4: Parafoudres à oxyde métallique sans éclateurs pour réseaux à courant alternatif
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Standards Content (Sample)
IEC 60099-4
®
Edition 2.0 2009-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
AMENDMENT 2
AMENDEMENT 2
Surge arresters –
Part 4: Metal-oxide surge arresters without gaps for a.c. systems
Parafoudres –
Partie 4: Parafoudres à oxyde métallique sans éclateurs pour réseaux à courant
alternatif
IEC 60099-4:2004/A2:2009
---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
IEC 60099-4
®
Edition 2.0 2009-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
AMENDMENT 2
AMENDEMENT 2
Surge arresters –
Part 4: Metal-oxide surge arresters without gaps for a.c. systems
Parafoudres –
Partie 4: Parafoudres à oxyde métallique sans éclateurs pour réseaux à courant
alternatif
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
M
CODE PRIX
ICS 29.240.10; 29.120.50 ISBN 978-2-88910-056-9
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 3 ----------------------
– 2 – 60099-4 Amend.2 © IEC:2009
FOREWORD
This amendment has been prepared by IEC technical committee 37: Surge arresters.
The text of this amendment is based on the following documents:
FDIS Report on voting
37/354/FDIS 37/357/RVD
Full information on the voting for the approval of this amendment can be found in the report
on voting indicated in the above table.
The committee has decided that the contents of this amendment and the base publication will
remain unchanged until the maintenance result date indicated on the IEC web site under
"http://webstore.iec.ch" in the data related to the specific publication. At this date, the
publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
_____________
Replace definitions 3.66, 3.67 and 3.68 with the following new definitions:
3.66
specified long-term load
SLL
force perpendicular to the longitudinal axis of an arrester, allowed to be continuously applied
during service without causing any mechanical damage to the arrester
3.67
specified short-term load
SSL
greatest force perpendicular to the longitudinal axis of an arrester, allowed to be applied
during service for short periods and for relatively rare events (for example, short-circuit
current loads and extreme wind gusts) without causing any mechanical damage to the
arrester
NOTE SSL does not relate to mechanical strength requirements for seismic loads. See M.2.
3.68
mean breaking load
MBL
the average breaking load for porcelain or cast resin-housed arresters determined from tests
---------------------- Page: 4 ----------------------
60099-4 Amend.2 © IEC:2009 – 3 –
6.14.1 Bending moment
Change NOTE 1 of Subclause 6.14.1 as follows:
NOTE 1 When determining the mechanical load applied to a surge arrester, the user should consider, for
example, wind, ice and electromagnetic forces likely to affect the installation.
Add the following subclause to 6.14:
6.14.4 Mean value of breaking load (MBL)
The MBL shall be ≥ 1,2 times the specified short-term load (SSL) (see 8.9.4).
Replace the existing Subclause 8.9 by the following new Subclause 8.9:
8.9 Test of the bending moment
This test applies to porcelain and cast-resin housed arresters for U > 52 kV. It also applies
m
to porcelain and cast-resin housed arresters for U ≤ 52 kV for which the manufacturer claims
m
cantilever strength.
The complete test procedure is shown by the flow chart in Annex M.
8.9.1 General
This test demonstrates the ability of the arrester to withstand the manufacturer's declared
values for bending loads. Normally, an arrester is not designed for torsional loading. If an
arrester is subjected to torsional loads, a specific test may be necessary by agreement
between manufacturer and user.
The test shall be performed on complete arrester units without internal overpressure. For
single-unit arrester designs, the test shall be performed on the longest unit of the design.
Where an arrester contains more than one unit or where the arrester has different specified
bending moments in both ends, the test shall be performed on the longest unit of each
different specified bending moment, with loads determined according to M.1.
The test shall be performed in two parts that may be done in any order:
– a bending moment test to determine the mean value of breaking load (MBL);
– a static bending moment test with the test load equal to the specified short-term load
(SSL), i.e. the 100 % value of M.3.
8.9.2 Sample preparation
One end of the sample shall be firmly fixed to a rigid mounting surface of the test equipment,
and a load shall be applied to the other (free) end of the sample to produce the required
bending moment at the fixed end. The direction of the load shall pass through and be
perpendicular to the longitudinal axis of the arrester. If the arrester is not axi-symmetrical with
respect to its bending strength, the manufacturer shall provide information regarding this non-
symmetric strength, and the load shall be applied in an angular direction that subjects the
weakest part of the arrester to the maximum bending moment.
---------------------- Page: 5 ----------------------
– 4 – 60099-4 Amend.2 © IEC:2009
8.9.3 Test procedure
8.9.3.1 Test procedure to determine mean value of breaking load (MBL)
Three samples shall be tested. If the test to verify the SSL (see 8.9.3.2) is performed first,
then samples from that test may be used for determination of MBL. The test samples need not
contain the internal parts. On each sample, the bending load shall be increased smoothly until
breaking occurs within 30 s to 90 s. “Breaking” includes fracture of the housing and damages
that may occur to fixing device or end fittings.
The mean breaking load, MBL, is calculated as the mean value of the breaking loads for the
test samples.
NOTE Care should be taken because the housing of an arrester can splinter while under load.
8.9.3.2 Test procedure to verify the specified short-term load (SSL)
Three samples shall be tested. The test samples shall contain the internal parts. Prior to the
tests, each test sample shall be subjected to a leakage check (see 9.1 d)) and an internal
partial discharge test (see 9.1 c)). If these tests have been performed as routine tests, they
need not be repeated at this time.
+5
On each sample, the bending load shall be increased smoothly to SSL, tolerance %, within
−0
30 s to 90 s. When the test load is reached, it shall be maintained for 60 s to 90 s. During this
time the deflection shall be measured. Then the load shall be released smoothly and the
residual deflection shall be recorded. The residual deflection shall be measured in the interval
1 min to 10 min after the release of the load.
NOTE 1 Care should be taken because the housing of an arrester may break and splinter while under load.
NOTE 2 Agreement must be made with the manufacturer if it is necessary for any reason to apply a load that is
more than 5 % above SSL.
8.9.4 Test evaluation
The arrester shall have passed the test if
– the mean value of breaking load, MBL, is ≥ 1,2 x SSL;
– for the SSL test
– there is no visible mechanical damage;
– the remaining permanent deflection is ≤ 3 mm or ≤ 10 % (whichever is greater) of
maximum deflection during the test;
– the test samples pass the leakage test in accordance with 9.1 d);
– the internal partial discharge level of the test samples does not exceed the value
specified in 9.1 c);
---------------------- Page: 6 ----------------------
60099-4 Amend.2 © IEC:2009 – 5 –
Replace the existing Subclause 8.10 by the following new Subclause 8.10:
8.10 Environmental tests
These tests apply to porcelain and cast resin-housed arresters.
8.10.1 General
The environmental tests demonstrate by accelerated test procedures that the sealing
mechanism and the exposed metal combinations of the arrester are not impaired by
environmental conditions.
The test shall be performed on complete arrester units of any length.
For arresters with an enclosed gas volume and a separate sealing system, the internal parts
may be omitted.
Arresters whose units differ only in terms of their lengths, and which are otherwise based on
the same design and material, and have the same sealing system in each unit, are considered
to be the same type of arrester.
8.10.2 Sample preparation
Prior to the tests, the test sample shall be subjected to the leakage check of 9.1 d).
8.10.3 Test procedure
The tests specified below shall be performed on one sample in the sequence given.
8.10.3.1 Temperature cycling test
The test shall be performed according to test Nb of IEC 60068-2-14.
The hot period shall be at a temperature of at least +40 °C, but not higher than
+70 °C. The cold period shall be at least 85 K below the value actually applied in the hot
period; however, the lowest temperature in the cold period shall not be lower than –50 °C:
– temperature change gradient: 1 K/min;
– duration of each temperature level: 3 h;
– number of cycles: 10.
8.10.3.2 Salt mist test
The test shall be performed according to Clauses 4 and Subclause 7.6, as applicable, of
IEC 60068-2-11:
– salt solution concentration: 5 % ± 1 % by weight;
– test duration: 96 h.
8.10.4 Test evaluation
The arrester shall have passed the tests if the sample passes the leakage check in
accordance with 9.1 d).
---------------------- Page: 7 ----------------------
– 6 – 60099-4 Amend.2 © IEC:2009
10.6 Requirements
Add the following items to 10.6:
6.14.1 Bending moment – reference to 10.8.9
6.14.3 Insulating base – reference to 10.8.9. Environmental tests do not apply
6.14.4 does not apply
10.8.1 General
Add the following items to 10.8.1:
9) Test of the bending moment – see 10.8.9
10) Environmental tests do not apply
Delete the following item from 10.8.1:
13) Moisture ingress test
10.8.9 Test of the bending moment
Replace the existing Subclause 10.8.9 by the following new Subclause 10.8.9:
10.8.9 Test of the bending moment
This test applies to polymer (except cast-resin) housed arresters (with and without enclosed
gas volume) for U > 52 kV. It also applies to polymer (except cast-resin) housed arresters
m
for U ≤ 52 kV for which the manufacturer claims cantilever strength.
m
Cast-resin housed arresters shall be tested according to 8.9. Arresters that have no declared
cantilever strength shall be submitted to the terminal torque preconditioning according to
10.8.9.3.1.1, the thermal preconditioning according to 10.8.9.3.1.3 and the water immersion
test according to 10.8.9.3.2.
The complete test procedure is shown by the flow chart in Annex M.
10.8.9.1 General
This test demonstrates the ability of the arrester to withstand the manufacturer's declared
values for bending loads. Normally, an arrester is not designed for torsional loading. If an
arrester is subjected to torsional loads, a specific test may be necessary by agreement
between manufacturer and user.
The test shall be performed on complete arrester units with the highest rated voltage of the
unit. For single-unit arrester designs, the test shall be performed on the longest unit with the
highest rated voltage of that unit of the design. Where an arrester contains more than one unit
or where the arrester has different specified bending moments in both ends, the test shall be
performed on the longest unit of each different specified bending moment, with loads
determined according to M.1. However, if the length of the longest unit is greater than
800 mm, a shorter length unit may be used, provided the following requirements are met:
– the length is at least as long as the greater of
– 800 mm
– three times the outside diameter of the housing (excluding the sheds) at the point it
enters the end fittings;
---------------------- Page: 8 ----------------------
60099-4 Amend.2 © IEC:2009 – 7 –
– the unit is one of the normal assortment of units used in the design, and is not specially
made for the test;
– the unit has the highest rated voltage of that unit of the design.
A test in three steps (two steps for arresters for U ≤ 52 kV) shall be performed one after the
m
other on three samples as follows:
– on all three test samples a cyclic test comprising 1000 cycles with the test load equal to
the specified long-term load (SLL);
– on two of the samples a static bending moment test with the test load equal to the
rd
specified short-term load (SSL), i.e. the 100 % value of M.3 and on the 3 sample a
mechanical preconditioning test as per 10.8.9.3.1;
– on all three samples a water immersion test as per 10.8.9.3.2.
+5
Tolerance on specified loads shall be % .
−0
NOTE 1 The cyclic test is not required for arresters for U ≤ 52 kV.
m
NOTE 2 If +5 % is exceeded this should be agreed upon with the manufacturer.
10.8.9.2 Sample preparation
The test samples shall contain the internal parts.
Prior to the test, each test sample shall be subjected to the following tests:
– electrical tests made in the following sequence:
– watt losses measured at U and at an ambient temperature of 20 °C ± 15 K;
c
– internal partial discharge test according to 9.1 c);
– residual voltage test at (0,01 to 1) times the nominal discharge current; the current
wave shape shall be in the range of T /T = (4 to 10)/(10 to 25) μs;
1 2
– leakage tests in accordance with 9.1 d) for arresters with enclosed gas volume and
separate sealing system.
If the partial discharge test according to 9.1 c) and the leakage test according to 9.1 d) have
been performed as routine tests they need not be repeated at this time.
One end of the sample shall be firmly fixed to a rigid mounting surface of the test equipment,
and a load shall be applied to the other (free) end of the sample to produce the required
bending moment at the fixed end. The direction of the load shall pass through and be
perpendicular to the longitudinal axis of the arrester. If the arrester is not axi-symmetrical with
respect to its bending strength, the manufacturer shall provide information regarding this non-
symmetric strength, and the load shall be applied in an angular direction that subjects the
weakest part of the arrester to the maximum bending moment.
10.8.9.3 Test procedure
The test shall be performed on three samples. For arresters for U > 52 kV, the test is
m
performed in three steps. For arresters for U ≤ 52 kV, the test is performed in two steps.
m
---------------------- Page: 9 ----------------------
– 8 – 60099-4 Amend.2 © IEC:2009
a) Arresters for U > 52 kV
m
Step 1:
– Subject all three samples to 1000 cycles of bending moment, each cycle comprising
loading from zero to specified long-term load (SLL) in one direction, followed by loading to
SLL in the opposite direction, then returning to zero load. The cyclic motion shall be
approximately sinusoidal in form, with a frequency in the range 0,01 Hz – 0,5 Hz.
NOTE Due to the control of the testing machine it may take some cycles to obtain the SLL. The maximum number
of these cycles should be agreed upon with the manufacturer. These cycles should not be included in the
prescribed 1000 cycles.
The maximum deflection during the test and any residual deflection shall be recorded. The
residual deflection shall be measured in the interval 1 min to 10 min after the release of the
load.
Step 2.1:
Subject two of the samples from step 1 to a bending moment test. The bending load shall be
increased smoothly to specified short-term load (SSL) within 30 s to 90 s. When the test load
is reached, it shall be maintained for 60 s to 90 s. During this time the deflection shall be
measured. Then the load shall be released smoothly.
The maximum deflection during the test and residual deflection shall be recorded. The
residual deflection shall be measured within 1 min to 10 min after the release of the load.
Step 2.2:
Subject the third sample from Step 1 to mechanical/thermal preconditioning according to
10.8.9.3.1.
Step 3:
Subject all three samples to the water immersion test according to 10.8.9.3.2.
b) Arresters for U ≤ 52 kV
m
Step 1.1:
Subject two samples to a bending moment test. The bending load shall be increased smoothly
to specified short-term load (SSL) within 30 s to 90 s. When the test load is reached, it shall
be maintained for 60 s to 90 s. During this time the deflection shall be measured. Then the
load shall be released smoothly.
The maximum deflection during the test and any residual deflection shall be recorded. The
residual deflection shall be measured in the interval 1 min to 10 min after the release of the
load.
Step 1.2:
Subject a third sample to mechanical/thermal preconditioning according to 10.8.9.3.1.
Step 2:
Subject all three samples to the water immersion test according to 10.8.9.3.2.
10.8.9.3.1 Mechanical/thermal preconditioning
This preconditioning constitutes part of the test procedure of 10.8.9.3 and shall be performed
on one of the test samples as defined in 10.8.9.3.
---------------------- Page: 10 ----------------------
60099-4 Amend.2 © IEC:2009 – 9 –
10.8.9.3.1.1 Terminal torque preconditioning
The arrester terminal torque specified by the manufacturer shall be applied to the test sample
for a duration of 30 s.
10.8.9.3.1.2 Thermo-mechanical preconditioning
This portion of the test applies only to arresters for which a cantilever strength is declared.
The sample is submitted to the specified long-term load (SLL) in four directions and in thermal
variations as described in Figures 6 and 7.
NOTE If, in particular applications, other loads are dominant, the relevant loads should be applied instead. The
total test time and temperature cycle should remain unchanged.
The thermal variations consist of two 48 h cycles of heating and cooling as described in
Figure 6. The temperature of the hot and cold periods shall be maintained for at least 16 h.
The test shall be conducted in air.
The applied static mechanical load shall be equal to SLL defined by the manufacturer. Its
direction changes every 24 h at any temperature in the transition from hot to cold, or from
cold to hot, as defined in Figure 7.
The test may be interrupted for maintenance for a total duration of 4 h and restarted after
interruption. The cycle then remains valid.
Any residual deflection measured from the initial no-load position shall be reported. The
residual deflection shall be measured within 1 min to 10 min after the release of the load.
10.8.9.3.1.3 Thermal preconditioning
This portion of the test applies only to arresters for which no cantilever strength is declared.
The sample is submitted to the thermal variations as described in Figure 6 without any load
applied.
The thermal variations consist of two 48 h cycles of heating and cooling as described in
Figure 6. The temperature of the hot and cold periods shall be maintained for at least 16 h.
The test shall be conducted in air.
10.8.9.3.2 Water immersion test
3
The test samples shall be kept immersed in a vessel, in boiling deionised water with 1 kg/m
of NaCl, for 42 h.
NOTE 1 The characteristics of the water described above are those measured at the beginning of the test.
NOTE 2 This temperature (boiling water) can be reduced to 80 °C (with a minimum duration of 52 h) by
agreement between the user and the manufacturer, if the manufacturer claims that its sealing material is not able
to withstand the boiling temperature for a duration of 42 h. This value of 52 h can be expanded up to 168 h (i.e.
one week) after agreement between the manufacturer and the user.
At the end of the boiling, the arrester shall remain in the vessel until the water cools to
approximately 50 °C and shall be maintained in the water at this temperature until verification
tests can be performed. The arrester shall be removed from the water and cooled to ambient
temperature for not longer than three thermal time constants of the sample (as derived from
the cooling curves of Annex B). The 50 °C holding temperature is necessary only if it is
necessary to delay the verification tests after the end of the water immersion test as shown in
Figure 8. Evaluation tests shall be made within the time specified in 10.8.9.4. After removing
the sample from the water it may be washed with tap water.
---------------------- Page: 11 ----------------------
– 10 – 60099-4 Amend.2 © IEC:2009
10.8.9.4 Test evaluation
Tests according to 10.8.9.2 shall be repeated on each test sample.
The arrester shall have passed the test if the following is demonstrated:
a) Arresters for U > 52 kV
m
After step 2:
– there is no visible damage;
– the slope of the force-deflection curve remains positive up to the SSL value except for dips
not exceeding 5 % of SSL magnitude. The sampling rate of digital measuring equipment
-1
shall be at least 10 s . The cut-off frequency of the measuring equipment shall be not less
than 5 Hz.
Maximum deflection during step 1 and 2 and any remaining permanent deflection after the
test shall be reported.
After step 3:
within 8 h after cooling as defined in Figure 8:
– the increase in watt losses, measured at U and at an ambient temperature that does not
c
deviate by more than 3 K from the initial measurements, is not more than the greater of
20 mW/kV of U (measured at U ) or 20 %;
c c
– the internal partial discharge measured at 1,05 times U does not exceed 10 pC;
c
at any time after the above watt losses and partial discharge measurements:
– for arresters with enclosed gas volume and separate sealing system, the samples pass
the leakage test in accordance with 9.1 d);
– the residual voltage measured on the complete sample at the same current value and
wave shape as the initial measurement is not more than 5 % different from the initial
measurement;
– the difference in voltage between two successive impulses at nominal discharge current
does not exceed 2 %, and the oscillograms of voltage and current do not reveal any
partial or full breakdown of the test sample. The current wave shape shall be in the range
of T /T = (4 to 10)/(10 to 25) μs, and the impulses shall be administered 50-60 s apart.
1 2
NOTE In case of extra long arresters where the blocks can be dismantled this part of the evaluation test can be
performed on individual blocks or stacks of blocks. If the blocks cannot be dismantled a possible procedure would
be to drill a hole in the arrester insulation to make contact with the internal stack at a metal spacer and in this way
be able to test shorter arrester sections.
– the change in reference voltage measured before and after the two residual voltage tests
does not exceed 2 %.
b) Arresters for U ≤ 52 kV
m
After step 1:
– there is no visible damage;
– for step 1.1, the slope of the force-deflection curve remains positive up to the SSL value
except for dips not exceeding 5 % of SSL magnitude. The sampling rate of digital
–1
measuring equipment shall be at least 10 s . The cut-off frequency of the measuring
equipment shall be not less than 5 Hz.
Maximum deflection during step 1 and any remaining permanent deflection after the test shall
be reported.
---------------------- Page: 12 ----------------------
60099-4 Amend.2 © IEC:2009 – 11 –
After step 2:
within 8 h after cooling as defined in Figure 8:
– the increase in watt losses, measured at U and at an ambient temperature that does not
c
deviate by more than 3 K from the initial measurements, is not more than the greater of
20 mW/kV of U (measured at U ) or 20 %;
c c
– the internal partial discharge measured at 1,05 times U does not exceed 10 pC;
c
at any time after the above watt losses and partial discharge measurements:
– for arresters with enclosed gas volume and separate sealing system, the samples pass
the leakage test in accordance with 9.1 d);
– the residual voltage measured at the same current value and wave shape as the initial
measurement is not more than 5 % different from the initial measurement;
– the difference in voltage between two successive impulses at nominal discharge current
does not exceed 2 %, and the oscillograms of voltage and current do not reveal any
partial or full breakdown of the test sample. The current wave shape shall be in the range
of T /T = (4 to 10)/(10 to 25) µs and the impulses shall be administered 50-60 s apart.
1 2
– the change in reference voltage measured before and after the two residual voltage tests
does not exceed 2 %.
NOTE In case of extra long arresters where the blocks can be dismantled, the residual voltage test can be
performed on individual blocks or stacks of blocks. If the blocks cannot be dismantled, a possible procedure would
be to drill a hole in the arrester insulation to make contact with the internal stack at a metal spacer and in this way
be able to test shorter arrester sections.
Delete Subclause 10.8.10.
Delete Subcl
...
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