{"id":254961,"date":"2024-10-19T16:51:03","date_gmt":"2024-10-19T16:51:03","guid":{"rendered":"https:\/\/pdfstandards.shop\/product\/uncategorized\/bs-en-60099-42014\/"},"modified":"2024-10-25T12:17:15","modified_gmt":"2024-10-25T12:17:15","slug":"bs-en-60099-42014","status":"publish","type":"product","link":"https:\/\/pdfstandards.shop\/product\/publishers\/bsi\/bs-en-60099-42014\/","title":{"rendered":"BS EN 60099-4:2014"},"content":{"rendered":"

IEC 60099-4:2014 applies to non-linear metal-oxide resistor type surge arresters without spark gaps designed to limit voltage surges on a.c. power circuits with Us above 1 kV. This third edition cancels and replaces the second edition published in 2009. This edition constitutes a technical revision. The numerous changes between the second and third editions are listed in the Foreward of the document. Keywords: testing of gapless metal-oxide surge arresters for a.c.power systems<\/p>\n

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PDF Pages<\/th>\nPDF Title<\/th>\n<\/tr>\n
4<\/td>\nForeword
Endorsement notice <\/td>\n<\/tr>\n
5<\/td>\nAnnex ZA (normative) Normative references to international publications with their corresponding European publications <\/td>\n<\/tr>\n
7<\/td>\nEnglish
CONTENTS <\/td>\n<\/tr>\n
16<\/td>\nINTRODUCTION <\/td>\n<\/tr>\n
17<\/td>\n1 Scope
2 Normative references <\/td>\n<\/tr>\n
18<\/td>\n3 Terms and definitions <\/td>\n<\/tr>\n
28<\/td>\n4 Identification and classification
4.1 Arrester identification
4.2 Arrester classification
Tables
Table 1 \u2013 Arrester classification <\/td>\n<\/tr>\n
29<\/td>\n5 Standard ratings and service conditions
5.1 Standard rated voltages
5.2 Standard rated frequencies
5.3 Standard nominal discharge currents
5.4 Service conditions
5.4.1 Normal service conditions
5.4.2 Abnormal service conditions
Table 2 \u2013 Preferred values of rated voltages <\/td>\n<\/tr>\n
30<\/td>\n6 Requirements
6.1 Insulation withstand
6.2 Reference voltage
6.3 Residual voltages <\/td>\n<\/tr>\n
31<\/td>\n6.4 Internal partial discharges
6.5 Seal leak rate
6.6 Current distribution in a multi-column arrester
6.7 Thermal stability
6.8 Long term stability under continuous operating voltage
6.9 Heat dissipation behaviour of test sample
6.10 Repetitive charge transfer withstand
6.11 Operating duty
6.12 Power-frequency voltage versus time characteristics of an arrester <\/td>\n<\/tr>\n
32<\/td>\n6.13 Short-circuit performance
6.14 Disconnector
6.14.1 Disconnector withstand
6.14.2 Disconnector operation
6.15 Requirements on internal grading components <\/td>\n<\/tr>\n
33<\/td>\n6.16 Mechanical loads
6.16.1 General
6.16.2 Bending moment
6.16.3 Resistance against environmental stresses
6.16.4 Insulating base and mounting bracket
6.16.5 Mean value of breaking load (MBL)
6.16.6 Electromagnetic compatibility
6.17 End of life
6.18 Lightning impulse discharge capability <\/td>\n<\/tr>\n
34<\/td>\n7 General testing procedure
7.1 Measuring equipment and accuracy
7.2 Reference voltage measurements
7.3 Test samples
7.3.1 General <\/td>\n<\/tr>\n
35<\/td>\n7.3.2 Arrester section requirements <\/td>\n<\/tr>\n
36<\/td>\n8 Type tests (design tests)
8.1 General <\/td>\n<\/tr>\n
37<\/td>\n8.2 Insulation withstand tests
8.2.1 General
Table 3 \u2013 Arrester type tests <\/td>\n<\/tr>\n
38<\/td>\n8.2.2 Tests on individual unit housings
8.2.3 Tests on complete arrester assemblies
8.2.4 Ambient air conditions during tests
8.2.5 Wet test procedure <\/td>\n<\/tr>\n
39<\/td>\n8.2.6 Lightning impulse voltage test
8.2.7 Switching impulse voltage test
8.2.8 Power-frequency voltage test <\/td>\n<\/tr>\n
40<\/td>\n8.3 Residual voltage tests
8.3.1 General
8.3.2 Steep current impulse residual voltage test <\/td>\n<\/tr>\n
41<\/td>\n8.3.3 Lightning impulse residual voltage test
8.3.4 Switching impulse residual voltage test
8.4 Test to verify long term stability under continuous operating voltage
8.4.1 General <\/td>\n<\/tr>\n
42<\/td>\n8.4.2 MO resistor elements stressed below Uref <\/td>\n<\/tr>\n
43<\/td>\n8.4.3 Test procedure for MO resistor elements stressed at or above Uref
Figures
Figure 1 \u2013 Illustration of power losses versus time during long term stability test <\/td>\n<\/tr>\n
46<\/td>\n8.5 Test to verify the repetitive charge transfer rating, Qrs
8.5.1 General <\/td>\n<\/tr>\n
47<\/td>\n8.5.2 Test procedure
Figure 2 \u2013 Test procedure to verify the repetitive charge transfer rating, Qrs <\/td>\n<\/tr>\n
48<\/td>\n8.5.3 Test evaluation
8.5.4 Rated values of repetitive charge transfer rating, Qrs <\/td>\n<\/tr>\n
49<\/td>\n8.6 Heat dissipation behaviour of test sample
8.6.1 General
8.6.2 Arrester section requirements
8.6.3 Procedure to verify thermal equivalency between complete arresterand arrester section
8.7 Operating duty test
8.7.1 General <\/td>\n<\/tr>\n
50<\/td>\n8.7.2 Test procedure <\/td>\n<\/tr>\n
51<\/td>\nFigure 3 \u2013 Test procedure to verify the thermal energy rating, Wth, and the thermal charge transfer rating, Qth, respectively <\/td>\n<\/tr>\n
52<\/td>\nTable 4 \u2013 Requirements for high current impulses <\/td>\n<\/tr>\n
53<\/td>\n8.7.3 Rated thermal energy and charge values, Wth and Qth <\/td>\n<\/tr>\n
54<\/td>\n8.8 Power-frequency voltage-versus-time test
8.8.1 General
Table 5 \u2013 Rated values of thermal charge transfer rating, Qth <\/td>\n<\/tr>\n
55<\/td>\n8.8.2 Test samples
Figure 4 \u2013 Test procedure to verify the power frequency versus time characteristic (TOV test) <\/td>\n<\/tr>\n
56<\/td>\n8.8.3 Initial measurements
8.8.4 Test procedure <\/td>\n<\/tr>\n
57<\/td>\n8.8.5 Test evaluation
8.9 Tests of arrester disconnector
8.9.1 General
8.9.2 Operating withstand test <\/td>\n<\/tr>\n
58<\/td>\n8.9.3 Disconnector operation <\/td>\n<\/tr>\n
59<\/td>\n8.9.4 Mechanical tests <\/td>\n<\/tr>\n
60<\/td>\n8.9.5 Temperature cycling and seal pumping test
8.10 Short-circuit tests
8.10.1 General <\/td>\n<\/tr>\n
61<\/td>\n8.10.2 Preparation of the test samples <\/td>\n<\/tr>\n
63<\/td>\nTable 6 \u2013 Test requirements for porcelain housed arresters <\/td>\n<\/tr>\n
64<\/td>\nFigure 5 \u2013 Examples of arrester units
Figure 6 \u2013 Examples of fuse wire locations for \u201cDesign A\u201c arresters <\/td>\n<\/tr>\n
65<\/td>\n8.10.3 Mounting of the test sample
Figure 7 \u2013 Examples of fuse wire locations for \u201cDesign B\u201c arresters
Figure 8 \u2013 Short-circuit test setup for porcelain-housed arresters <\/td>\n<\/tr>\n
66<\/td>\n8.10.4 High-current short-circuit tests <\/td>\n<\/tr>\n
67<\/td>\nTable 7 \u2013 Required currents for short-circuit tests <\/td>\n<\/tr>\n
69<\/td>\n8.10.5 Low-current short-circuit test
8.10.6 Evaluation of test results
8.11 Test of the bending moment
8.11.1 General
8.11.2 Overview <\/td>\n<\/tr>\n
70<\/td>\n8.11.3 Sample preparation
8.11.4 Test procedure
8.11.5 Test evaluation <\/td>\n<\/tr>\n
71<\/td>\n8.11.6 Test on insulating base and mounting bracket
8.12 Environmental tests
8.12.1 General
8.12.2 Sample preparation
8.12.3 Test procedure <\/td>\n<\/tr>\n
72<\/td>\n8.12.4 Test evaluation
8.13 Seal leak rate test
8.13.1 General
8.13.2 Sample preparation
8.13.3 Test procedure
8.13.4 Test evaluation
8.14 Radio interference voltage (RIV) test <\/td>\n<\/tr>\n
74<\/td>\n8.15 Test to verify the dielectric withstand of internal components
8.15.1 General
8.15.2 Test procedure
8.15.3 Test evaluation
8.16 Test of internal grading components
8.16.1 Test to verify long term stability under continuous operating voltage <\/td>\n<\/tr>\n
75<\/td>\n8.16.2 Thermal cyclic test <\/td>\n<\/tr>\n
76<\/td>\n9 Routine tests and acceptance tests
9.1 Routine tests <\/td>\n<\/tr>\n
77<\/td>\n9.2 Acceptance tests
9.2.1 Standard acceptance tests <\/td>\n<\/tr>\n
78<\/td>\n9.2.2 Special thermal stability test
10 Test requirements on polymer-housed surge arresters
10.1 Scope
10.2 Normative references
10.3 Terms and definitions
10.4 Identification and classification
10.5 Standard ratings and service conditions
10.6 Requirements <\/td>\n<\/tr>\n
79<\/td>\n10.7 General testing procedure
10.8 Type tests (design tests)
10.8.1 General
10.8.2 Insulation withstand tests
10.8.3 Residual voltage tests <\/td>\n<\/tr>\n
80<\/td>\n10.8.4 Test to verify long term stability under continuous operating voltage
10.8.5 Test to verify the repetitive charge transfer rating, Qrs
10.8.6 Heat dissipation behaviour of test sample
10.8.7 Operating duty tests
10.8.8 Power frequency voltage-versus-time test <\/td>\n<\/tr>\n
81<\/td>\n10.8.9 Tests of arrester disconnector
10.8.10 Short-circuit tests <\/td>\n<\/tr>\n
83<\/td>\nTable 8 \u2013 Test requirements for polymer-housed arresters <\/td>\n<\/tr>\n
84<\/td>\nFigure 9 \u2013 Short-circuit test setup for polymer-housed arresters <\/td>\n<\/tr>\n
86<\/td>\nFigure 10 \u2013 Example of a test circuit for re-applying pre-failing circuit immediately before applying the short-circuit test current <\/td>\n<\/tr>\n
87<\/td>\n10.8.11 Test of the bending moment <\/td>\n<\/tr>\n
90<\/td>\nFigure 11 \u2013 Thermomechanical test <\/td>\n<\/tr>\n
91<\/td>\nFigure 12 \u2013 Example of the test arrangement for the thermomechanical test and direction of the cantilever load <\/td>\n<\/tr>\n
92<\/td>\nFigure 13 \u2013 Water immersion <\/td>\n<\/tr>\n
94<\/td>\n10.8.12 Environmental tests
10.8.13 Seal leak rate test
10.8.14 Radio interference voltage (RIV) test
10.8.15 Test to verify the dielectric withstand of internal components
10.8.16 Test of internal grading components
10.8.17 Weather ageing test <\/td>\n<\/tr>\n
96<\/td>\n10.9 Routine tests
11 Test requirements on gas-insulated metal enclosed arresters (GIS-arresters)
11.1 Scope
11.2 Normative references
11.3 Terms and definitions
11.4 Identification and classification <\/td>\n<\/tr>\n
97<\/td>\n11.5 Standard ratings and service conditions
11.6 Requirements
11.6.1 Withstand voltages <\/td>\n<\/tr>\n
98<\/td>\nTable 9 \u2013 10\u00a0kA and 20\u00a0kA three\u2013phase GIS\u2013arresters \u2013 Required withstand voltages <\/td>\n<\/tr>\n
99<\/td>\nTable 10 \u2013 2,5\u00a0kA and 5\u00a0kA three \u2013 phase \u2013 GIS arresters \u2013 Required withstand voltages <\/td>\n<\/tr>\n
100<\/td>\n11.7 General testing procedures
11.8 Type tests (design tests)
11.8.1 General
11.8.2 Insulation withstand tests <\/td>\n<\/tr>\n
103<\/td>\n11.8.3 Residual voltage tests
11.8.4 Test to verify long term stability under continuous operating voltage
11.8.5 Test to verify the repetitive charge transfer rating, Qrs
11.8.6 Heat dissipation behaviour of test sample
11.8.7 Operating duty tests
11.8.8 Power frequency voltage-versus-time test
11.8.9 Tests of arrester disconnector
11.8.10 Short-circuit tests
11.8.11 Test of the bending moment <\/td>\n<\/tr>\n
104<\/td>\n11.8.12 Environmental tests
11.8.13 Seal leak rate test
11.8.14 Radio interference voltage (RIV) test
11.8.15 Test to verify the dielectric withstand of internal components
11.8.16 Test of internal grading components
11.9 Routine tests
11.10 Test after erection on site
12 Separable and dead-front arresters
12.1 Scope <\/td>\n<\/tr>\n
105<\/td>\n12.2 Normative references
12.3 Terms and definitions
12.4 Identification and classification
12.5 Standard ratings and service conditions
12.6 Requirements <\/td>\n<\/tr>\n
106<\/td>\n12.7 General testing procedure
12.8 Type tests (design tests)
12.8.1 General
12.8.2 Insulation withstand tests <\/td>\n<\/tr>\n
107<\/td>\nFigure 14 \u2013 Test set-up for insulation withstand test of unscreened separable arresters
Table 11 \u2013 Insulation withstand test voltages for unscreened separable arresters <\/td>\n<\/tr>\n
108<\/td>\n12.8.3 Residual voltage tests
12.8.4 Test to verify long term stability under continuous operating voltage
Table 12 \u2013 Insulation withstand test voltages for dead-front arresters or separable arresters in a screened\/shielded housing <\/td>\n<\/tr>\n
109<\/td>\n12.8.5 Test to verify the repetitive charge transfer rating, Qrs
12.8.6 Heat dissipation behaviour of test sample
12.8.7 Operating duty tests <\/td>\n<\/tr>\n
110<\/td>\n12.8.8 Power-frequency voltage versus time test
12.8.9 Tests of disconnector
12.8.10 Short-circuit test <\/td>\n<\/tr>\n
111<\/td>\n12.8.11 Test of the bending moment
12.8.12 Environmental tests
12.8.13 Seal leak rate test
12.8.14 Radio interference voltage (RIV) test <\/td>\n<\/tr>\n
112<\/td>\n12.8.15 Test to verify the dielectric withstand of internal components
12.8.16 Test of internal grading components
12.8.17 Internal partial discharge test
12.9 Routine tests and acceptance tests
13 Liquid-immersed arresters
13.1 Scope
Table 13 \u2013 Partial discharge test values for separable and dead-front arresters <\/td>\n<\/tr>\n
113<\/td>\n13.2 Normative references
13.3 Terms and definitions
13.4 Identification and classification
13.5 Standard ratings and service conditions
13.6 Requirements <\/td>\n<\/tr>\n
114<\/td>\n13.7 General testing procedure
13.8 Type tests (design tests)
13.8.1 General
13.8.2 Insulation withstand tests
13.8.3 Residual voltage tests <\/td>\n<\/tr>\n
115<\/td>\n13.8.4 Test to verify long term stability under continuous operating voltage
13.8.5 Test to verify the repetitive charge transfer rating, Qrs <\/td>\n<\/tr>\n
116<\/td>\n13.8.6 Heat dissipation behaviour of test sample
13.8.7 Operating duty tests
13.8.8 Power frequency voltage-versus-time test
13.8.9 Tests of arrester disconnector
13.8.10 Short-circuit tests <\/td>\n<\/tr>\n
118<\/td>\n13.8.11 Test of the bending moment
13.8.12 Environmental tests <\/td>\n<\/tr>\n
119<\/td>\n13.8.13 Seal leak rate test
13.8.14 Radio interference voltage (RIV) test
13.8.15 Test to verify the dielectric withstand of internal components
13.8.16 Test of internal grading components
13.9 Routine tests and acceptance tests <\/td>\n<\/tr>\n
120<\/td>\nAnnex A (normative) Abnormal service conditions <\/td>\n<\/tr>\n
121<\/td>\nAnnex B (normative) Test to verify thermal equivalency between complete arrester and arrester section <\/td>\n<\/tr>\n
123<\/td>\nAnnex C (normative) Artificial pollution test with respect to the thermal stress on porcelain housed multi-unit metal-oxide surge arresters
C.1 Glossary
C.1.1 Measured quantities
C.1.2 Calculated quantities <\/td>\n<\/tr>\n
124<\/td>\nC.2 General <\/td>\n<\/tr>\n
126<\/td>\nFigure C.1 \u2013 Flow-chart showing the procedure for determining the preheating of a test sample <\/td>\n<\/tr>\n
127<\/td>\nC.3 Classification of site severity
C.4 Preliminary heating test: measurement of the thermal time constant \u03c4
\nand calculation of \u03b2
Table C.1 \u2013 Mean external charge for different pollution severities <\/td>\n<\/tr>\n
128<\/td>\nC.5 Verification of the need to perform the pollution tests
C.6 General requirements for the pollution test
C.6.1 Test sample <\/td>\n<\/tr>\n
129<\/td>\nC.6.2 Testing plant
C.6.3 Measuring devices and measuring procedures
Table C.2 \u2013 Characteristic of the sample used for the pollution test
Table C.3 \u2013 Requirements for the device used for the measurement of the charge <\/td>\n<\/tr>\n
130<\/td>\nTable C.4 \u2013 Requirements for the device used for the measurement of the temperature <\/td>\n<\/tr>\n
131<\/td>\nC.6.4 Test preparation
C.7 Test procedures
C.7.1 Slurry method <\/td>\n<\/tr>\n
133<\/td>\nC.7.2 Salt fog method <\/td>\n<\/tr>\n
134<\/td>\nC.8 Evaluation of test results
C.8.1 Calculation of Kie <\/td>\n<\/tr>\n
135<\/td>\nC.8.2 Calculation of the expected temperature rise \u0394Tz in service
C.8.3 Preparation for the operating duty test
C.9 Example <\/td>\n<\/tr>\n
136<\/td>\nC.9.1 Preliminary heating test
C.9.2 Verification of the need to perform the pollution test
C.9.3 Salt fog tests
Table C.5 \u2013 Calculated values of \u0394Tz max for the selected example <\/td>\n<\/tr>\n
137<\/td>\nC.9.4 Calculation performed after five test cycles
Table C.6 \u2013 Results of the salt fog test for the selected example <\/td>\n<\/tr>\n
138<\/td>\nC.9.5 Calculation performed after 10 test cycles
Table C.7 \u2013 Calculated values of \u0394Tz and of TOD after 5 cycles for the selected example
Table C.8 \u2013 Calculated values of \u0394Tz and of TOD after 10 cycles for the selected example <\/td>\n<\/tr>\n
139<\/td>\nAnnex D (informative) Typical information given with enquiries and tenders
D.1 Information given with enquiry
D.1.1 System data
D.1.2 Service conditions
D.1.3 Arrester duty <\/td>\n<\/tr>\n
140<\/td>\nD.1.4 Characteristics of arrester
D.1.5 Additional equipment and fittings
D.1.6 Any special abnormal conditions
D.2 Information given with tender <\/td>\n<\/tr>\n
141<\/td>\nAnnex E (informative) Ageing test procedure \u2013 Arrhenius law \u2013 Problems with higher temperatures
Table E.1 \u2013 Minimum demonstrated lifetime prediction
Table E.2 \u2013 Relationship between test durations at 115 oC and equivalent time at upper limit of ambient temperature <\/td>\n<\/tr>\n
143<\/td>\nAnnex F (informative) Guide for the determination of the voltage distribution along metal-oxide surge arresters
F.1 General
F.2 Modelling of the surge arrester <\/td>\n<\/tr>\n
144<\/td>\nF.3 Modelling of the boundary conditions
F.4 Calculation procedure
F.4.1 Capacitive representation of the MO resistor column <\/td>\n<\/tr>\n
145<\/td>\nF.4.2 Capacitive and resistive representation of the MO resistor column
F.4.3 Determination of Uct
F.5 Example calculations <\/td>\n<\/tr>\n
146<\/td>\nF.5.1 Modelling of the arrester and the boundary conditions
F.5.2 Resistive effects of the metal-oxide MO resistors
F.5.3 Results and conclusions from electric field calculations <\/td>\n<\/tr>\n
147<\/td>\nFigure F.1 \u2013 Typical three-phase arrester installation
Table F.1 \u2013 Results from example calculations <\/td>\n<\/tr>\n
148<\/td>\nFigure F.2 \u2013 Simplified multi-stage equivalent circuit of an arrester <\/td>\n<\/tr>\n
149<\/td>\nFigure F.3 \u2013 Geometry of arrester model <\/td>\n<\/tr>\n
150<\/td>\nFigure F.4 \u2013 Example of voltage-current characteristic of MO resistors at +20 \u00b0C in the leakage current region
Figure F.5 \u2013 Calculated voltage stress along the MO resistor column in case B <\/td>\n<\/tr>\n
151<\/td>\nAnnex G (normative) Mechanical considerations
G.1 Test of bending moment
Figure G.1 \u2013 Bending moment \u2013 multi-unit surge arrester <\/td>\n<\/tr>\n
152<\/td>\nG.2 Seismic test
G.3 Definition of mechanical loads <\/td>\n<\/tr>\n
153<\/td>\nG.4 Definition of seal leak rate
Figure G.2 \u2013 Definition of mechanical loads <\/td>\n<\/tr>\n
154<\/td>\nG.5 Calculation of wind-bending-moment
Figure G.3 \u2013 Surge arrester unit <\/td>\n<\/tr>\n
155<\/td>\nG.6 Procedures of tests of bending moment for porcelain\/cast resin and polymer-housed arresters
Figure G.4 \u2013 Surge-arrester dimensions <\/td>\n<\/tr>\n
156<\/td>\nFigure G.5 \u2013 Flow chart of bending moment test procedures <\/td>\n<\/tr>\n
157<\/td>\nAnnex H (normative) Test procedure to determine the lightning impulse discharge capability
H.1 General
H.2 Selection of test samples <\/td>\n<\/tr>\n
158<\/td>\nH.3 Test procedure
H.4 Test parameters for the lightning impulse discharge capability test
H.5 Measurements during the lightning impulse discharge capability test
H.6 Rated lightning impulse discharge capability <\/td>\n<\/tr>\n
159<\/td>\nH.7 List of rated energy values
H.8 List of rated charge values <\/td>\n<\/tr>\n
160<\/td>\nAnnex I (normative) Determination of the start temperature in tests including verification of thermal stability <\/td>\n<\/tr>\n
161<\/td>\nAnnex J (normative) Determination of the average temperature of a multi-unit high-voltage arrester <\/td>\n<\/tr>\n
162<\/td>\nFigure J.1 \u2013 Determination of average temperature in case of arrester units of same rated voltages
Figure J.2 \u2013 Determination of average temperature in case of arrester units of different rated voltages <\/td>\n<\/tr>\n
163<\/td>\nAnnex K (informative) Example calculation of test parameters for the operating duty test (8.7) according to the requirements of 7.3 <\/td>\n<\/tr>\n
164<\/td>\nAnnex L (informative) Comparison of the old energy classification system based on line discharge classes and the new classification system based on thermal energy ratings for operating duty tests and repetitive charge transfer ratings for repetitive single event energies
Table L.1 \u2013 Peak currents for switching impulse residual voltage test <\/td>\n<\/tr>\n
165<\/td>\nFigure L.1 \u2013 Specific energy in kJ per\u00a0kV rating dependant on the ratio of switching impulse residual voltage (Ua) to the r.m.s. value of the rated voltage Ur of the arrester
Table L.2 \u2013 Parameters for the line discharge test on 20\u00a0000\u00a0A and 10\u00a0000\u00a0A arresters <\/td>\n<\/tr>\n
167<\/td>\nTable L.3 \u2013 Comparison of the classification system accordingto IEC\u00a060099-4:2009 (Ed.2.2) and to IEC\u00a060099-4:2014 (Ed.3.0) <\/td>\n<\/tr>\n
170<\/td>\nBibliography <\/td>\n<\/tr>\n<\/table>\n","protected":false},"excerpt":{"rendered":"

Surge arresters – Metal-oxide surge arresters without gaps for a.c. systems<\/b><\/p>\n\n\n\n\n
Published By<\/td>\nPublication Date<\/td>\nNumber of Pages<\/td>\n<\/tr>\n
BSI<\/b><\/a><\/td>\n2014<\/td>\n172<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n","protected":false},"featured_media":254966,"template":"","meta":{"rank_math_lock_modified_date":false,"ep_exclude_from_search":false},"product_cat":[511,2641],"product_tag":[],"class_list":{"0":"post-254961","1":"product","2":"type-product","3":"status-publish","4":"has-post-thumbnail","6":"product_cat-29-120-50","7":"product_cat-bsi","9":"first","10":"instock","11":"sold-individually","12":"shipping-taxable","13":"purchasable","14":"product-type-simple"},"_links":{"self":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product\/254961","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/types\/product"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/media\/254966"}],"wp:attachment":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/media?parent=254961"}],"wp:term":[{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product_cat?post=254961"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product_tag?post=254961"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}