How to choose surge protective device SPD manufacturer
8 important points of purchasing pluggable surge protective device from China
We LSP a China manufacturer since 2010, focus our efforts on the development of surge protection and on the production of AC DC PV surge protective devices, strive to serve our customers with high quality products.
If you are an electric appliance importer, agent, distributor, dealer or retailer, when you buy AC and DC or PV SPDs (surge protective devices), you should know 8 important points of purchasing replaceable pluggable surge protective device (SPD) from China
1. Raw material
(1.1) Metal Oxide Varistor – MOV
As a core component of inside SPDs, needless to say, SPD quality mainly depend on varistors quality. Obviously use quality MOV getting more important, there is many famous brand metal oxide varistors for selection such as EPCOS/TDK, Littelfuse, Keko, Varsi …
World famous brand
| Brand | Photo |
| EPCOS/TDK |  |
| Littelfuse |  |
| Keko |  |
| Varsi |  |
| … | … |
Most of China AC&DC surge protective device SPD manufacturer (factory) use China domestic metal oxide varistor (MOV), there is many brand for selection. list some for reference.
| Brand | Photo |
| CJP (Changzhou ChuangJie Lighting Protection Co., Ltd.) |  |
| LKD (Longke Electronic) |  |
| BCTEQ (Dongguan BCTEQ Electroncis Co., Ltd.) |  |
| KVR (Kestar Electronic Co., Ltd.) |  |
| Leytun (Foshan Leytun Electric Co., Ltd.) |  |
| … | … |
After you select a varistor (MOV) brand, how do you know choose the correct MOV voltage? Dont’ worry, let us guide you to choose right varistor.
Let’s see the MOV technical parameters firstly, list as below.
Metal Oxide Varistor (MOV) Technical Parameters
| Model | Performance data TA=+25℃ | Rated value T=+85℃ | ||||||||
| Varistor voltage | Standard tolerance | Limiting voltage at IP (8/20μs) | Capacitance (1kHz) | Max. continuous working voltage (UC) | Energy (2ms) | Discharge current IMAX (8/20μs) | Rated power | |||
| VN (V) | △VN (±%) | VP (V) | IP (A) | C (pF) | VRMS (V) | VDC (V) | WMAX (J) | IMAX (A) | PMAX (W) | |
| CJA34S-121 | 120 | 10 | 200 | 300 | 8000 | 75 | 100 | 230 | 40000 | 1.4 |
| CJA34S-201 | 205 | 10 | 340 | 300 | 7900 | 130 | 170 | 310 | 40000 | 1.4 |
| CJA34S-221 | 220 | 10 | 360 | 300 | 7200 | 140 | 180 | 340 | 40000 | 1.4 |
| CJA34S-241 | 240 | 10 | 395 | 300 | 6600 | 150 | 200 | 360 | 40000 | 1.4 |
| CJA34S-271 | 270 | 10 | 455 | 300 | 5600 | 175 | 225 | 390 | 40000 | 1.4 |
| CJA34S-331 | 330 | 10 | 550 | 300 | 5000 | 210 | 275 | 430 | 40000 | 1.4 |
| CJA34S-361 | 360 | 10 | 595 | 300 | 4400 | 230 | 300 | 460 | 40000 | 1.4 |
| CJA34S-391 | 390 | 10 | 650 | 300 | 4100 | 250 | 320 | 490 | 40000 | 1.4 |
| CJA34S-431 | 430 | 10 | 710 | 300 | 3800 | 275 | 350 | 550 | 40000 | 1.4 |
| CJA34S-471 | 470 | 10 | 775 | 300 | 3400 | 300 | 385 | 600 | 40000 | 1.4 |
| CJA34S-511 | 510 | 10 | 840 | 300 | 3200 | 320 | 410 | 640 | 40000 | 1.4 |
| CJA34S-561 | 560 | 10 | 915 | 300 | 2900 | 350 | 460 | 710 | 40000 | 1.4 |
| CJA34S-621 | 620 | 10 | 1025 | 300 | 2600 | 385 | 505 | 800 | 40000 | 1.4 |
| CJA34S-681 | 680 | 10 | 1120 | 300 | 2400 | 420 | 560 | 910 | 40000 | 1.4 |
| CJA34S-751 | 750 | 10 | 1240 | 300 | 2200 | 460 | 615 | 960 | 40000 | 1.4 |
| CJA34S-781 | 780 | 10 | 1290 | 300 | 2100 | 485 | 640 | 930 | 40000 | 1.4 |
| CJA34S-821 | 820 | 10 | 1355 | 300 | 2000 | 510 | 670 | 940 | 40000 | 1.4 |
| CJA34S-911 | 910 | 10 | 1500 | 300 | 1800 | 550 | 745 | 960 | 40000 | 1.4 |
| CJA34S-951 | 950 | 10 | 1500 | 300 | 1700 | 580 | 760 | 1000 | 40000 | 1.4 |
| CJA34S-102 | 1000 | 10 | 1650 | 300 | 1600 | 625 | 825 | 1040 | 40000 | 1.4 |
| CJA34S-112 | 1100 | 10 | 1815 | 300 | 1500 | 680 | 895 | 1100 | 40000 | 1.4 |
| CJA34S-122 | 1200 | 10 | 2000 | 300 | 1300 | 750 | 970 | 1200 | 40000 | 1.4 |
| CJA34S-142 | 1400 | 10 | 2290 | 300 | 1100 | 880 | 1150 | 1300 | 40000 | 1.4 |
| CJA34S-162 | 1600 | 10 | 2550 | 300 | 1000 | 900 | 1200 | 1400 | 40000 | 1.4 |
| CJA34S-182 | 1800 | 10 | 2800 | 300 | 900 | 1000 | 1300 | 1500 | 40000 | 1.4 |
If you want to order SLP40-275/4 (UC=275Vac, IMAX=40kA), please see the table (we remark it red), the column of Max. continuous working voltage (UC) – VRMS (V), find the data 275V, we’ll find model is CJA34S-431.
P.S.
CJ: means CJ brand.
A: means AC
34S: means 34mm square
431: means varistor voltage is 430V
After select metal oxide varistor (MOV), we still need to pay attention to how to place it into SPD housing. there is two method:
A. insulation coated varistor, usually coated with green or blue color for moisture-proof.
B. Some SPDs manufacturer use naked varistor with contactor, it need use epoxy resin to embedment. Need to know epoxy resin is not environmental-friendly, famous SPDs brand do not do that any more.
C. For reduce the cost, some SPDs manufacturer use small varistor to replace 34S varistor, let’s take an example, if you want to purchase quality SPDs, hope the Nominal discharge current (8/20μs) In= 20kA and Maximum discharge current (8/20μs) Imax= 40kA, it should use 34S varistor (34 means 34mm; “S” means square), but they use small varistor such as 20D, 25D, 32D to replace 34S. List these varistors technical data as below:
| Technical data | Discharge current | MOV size | Photo |
| Nominal discharge current (8/20μs) In | 5 kA | 20D 20MM D: diameter |  |
| Maximum discharge current (8/20μs) Imax | 10 kA |
| Technical data | Discharge current | MOV size | Photo |
| Nominal discharge current (8/20μs) In | 10 kA | 25D 25MM D: diameter |  |
| Maximum discharge current (8/20μs) Imax | 20 kA |
| Technical data | Discharge current | MOV size | Photo |
| Nominal discharge current (8/20μs) In | 20 kA | 34S 34MM S: square |  |
| Maximum discharge current (8/20μs) Imax | 40 kA |
| Technical data | Discharge current | MOV size | Photo |
| Nominal discharge current (8/20μs) In | 20 kA | 34S 34MM S: square |  |
| Lightning impulse current (10/350μs) Iimp | 7 kA |
| Technical data | Discharge current | MOV size | Photo |
| Nominal discharge current (8/20μs) In | 20 kA | 48S 48MM |  |
| Lightning impulse current (10/350μs) Iimp | 12,5 kA |
(1.2) When select Gas Discharge Tube GDT for NPE pole, need to pay attention to
| Technical data | Discharge current | GDT size | Photo |
| Nominal discharge current (8/20μs) In | 10 kA | Diameter: 8mm |  |
| Maximum discharge current (8/20μs) Imax | 20 kA |
| Technical data | Discharge current | GDT size | Photo |
| Nominal discharge current (8/20μs) In | 20 kA | Diameter: 16mm |  |
| Maximum discharge current (8/20μs) Imax | 40 kA |
| Technical data | Discharge current | GDT size | Photo |
| Nominal discharge current (8/20μs) In | 20 kA | Diameter: 30mm |  |
| Lightning impulse current (10/350μs) Iimp | 25 kA |
| Technical data | Discharge current | GDT size | Photo |
| Nominal discharge current (8/20μs) In | 20 kA | Diameter: 30mm |  |
| Lightning impulse current (10/350μs) Iimp | 50 kA |
| Technical data | Discharge current | GDT size | Photo |
| Nominal discharge current (8/20μs) In | 20 kA | Diameter: 30mm |  |
| Lightning impulse current (10/350μs) Iimp | 100 kA |
(1.3) Internal structure design
Too many brand SPDs in market, you’ll see there is mainly two style internal structure design in pluggable modular: Dehn style and OBO style
OBO style:
when huge surge current coming, the width of metal connection part is too narrow, can’t withstand 40kA surge current.
Dehn style:
Thanks to reasonable design, it can withstand the Imax=40kA surge current.
(1.4) Plastic housing
quality material is PA66 or nylon for fire prevention.
(1.5) Metal parts, core metal material should be cooper metal, not steel.
OBO style use steel metal parts:
Dehn style use cooper metal parts:
(1.6) Environmental protection material
Some factory uses epoxy resin to seal. Epoxy resin is smelly and not good for environmental protection and health.
We use insulation coated varistor, don’t need epoxy resin, it is better for environmental protection.
2. Production automation
Metal parts connect with MOV (varistor) should be welding reliably. if manual welding, it easily happen insufficient solder. So automatic welding could keep product quality consistency. https://www.youtube.com/watch?v=RHwNJv8hobE
3. Laboratory and testing
As a SPDs manufacturer, must have a whole set testing equipments to test product whether co mpliance to:
| Standards | Items | Test classification / Test Category |
| IEC61643-11:2011 | AC SPDs | Class I,I+II, II, II+III |
| EN61643-11:2012 | AC SPDs | Type 1, 1+2, 2, 2+3 / T1, T1+T2, T2, T2+T3 |
| IEC61643-31:2018 | PV SPDs | Class I+II, II |
| EN50539-11:2013 | PV SPDs | Type 1+2, Type 2 / T1+T2, T2 |
AC standards and test classification:
| EN 61643-11:2012 | IEC 61643-11:2011 | VDE 0675-6-11:2002 | In (80/20μs) | Imax (8/20μs) | Iimp (10/350μs) | Uoc (1.2/50μs) |
| T1 | Class I | Class B | 25 kA | 65 kA | 25 kA | / |
| T1+T2 | Class I+II | Class B+C | 12.5~20 kA | 50 kA | 7 kA | / |
| 12.5kA | ||||||
| T2 | Class II | Class C | 20 kA | 40kA | / | / |
| T2+T3 (or T3) | Class II+III (or III) | Class C+D (or D) | 10 kA | 20kA | / | 10 kV 6 kV |
PV SPDs standards and test classification:
| EN 50539-11:2013 | IEC 61643-31:2018 | VDE 0675-39-11:2013 | In (80/20μs) | Imax (8/20μs) | Iimp (10/350μs) |
| T1+T2 | Class I+II | Class B+C | 20 kA | 40 kA | 6.25 kA / pole Itotal: 12.5kA |
| T2 | Class II | Class C | 20 kA | 40kA | / |
We have testing equipments list as below:
(1) Surge generator (Imax up to 150kA [8/20μs]; Iimp up to 25kA [10/350μs])
(2) Combination waveform 1.2/50μs impulse voltage & current generator (Uoc: 6kV [1.2/50μs]; Imax 4kA [8/20μs])
(3) Thermal stability tester
4. Workshop management
5. Certificate:
- Material: RoHS
- Management: ISO9001: 2015
- Environmental protection: ISO14001: 2015
- Occupational Health and Safety Assessment: OHSAS18001
- Authoritative product type test report and certificate, such as TUV, CB, CE, EAC, RoHS
https://www.lsp-international.com/tuv-cb-ce-eac-rohs-certificate-for-spd/
IEC 61643-11:2011 / EN 61643-11:2012 International Standard – Are your Surge Protective Devices (SPDs) tested and compliant?
Surge Protective Devices Must Meet Standards
IEC 61643-11:2011 / EN 61643-11:2012 Low-voltage surge protective devices – Part 11 Surge protective devices connected to low-voltage power systems – Requirements and test methods
Surge protective devices (SPDs) must provide defined protective functions and performance parameters in order to be suitable for use in corresponding protection concepts. As such, they are developed, tested, and classified according to their own international series of product standards.
Surge protective devices connected to low-voltage power systems are subjected to the requirements and test methods specified by the latest IEC 61643-11:2011 / EN 61643-11:2012 International Standard.
A true mark of quality is a product certification and approval from an independent testing institute. This confirms the fulfillment of the latest state-of-art product standard to ensure highest safety and integrity of the SPDs. The regulatory requirements placed on SPDs often require highly complex tests that only a few testing laboratories in the world are fully capable of carrying out.
How do you know?
The quality and performance of surge protective devices are hard for a customer to assess. Correct functioning can only be tested in suitable laboratories. Besides the external appearance and haptics, only the technical data provided by the manufacturer can provide any guidance. Even more important is a reliable statement from the manufacturer & certification/approval regarding the performance of the SPD and the execution of the tests specified in the respective product standard from series IEC 61643-11:2011 / EN 61643-11:2012
List the certification corresponding to standards
| Standards | Test classification | Certification |
| IEC 61643-11:2011 | Class I,I+II, II, II+III | CB |
| EN 61643-11:2012 | T1, T1+T2, T2, T2+T3 | TUV-mark, KEMA, CE |
| UL 1449 4th | T1, T2, T3, T4, T5 | UL, ETL, cTUVus |
6. Factory registration time and the main product line.
(6.1) Should check manufacturer’s business license, long time focus on lighting and surge protection field, it means the factory is more professional.
(6.2) Main product line. professional supplier should focus on lightning and surge protection field. The product line may include:
A. AC and DC power supply system surge protective devices
B. Data / signal line surge protector
C. RF coaxial surge protection devices
D. Lighting Rod, lightning event counter, earth rod, down conductor etc.
7. Product Warranty
Famous brand such as Dehn, OBO, they provide 5 years warranty. if manufacturer make sure they supply quality product, it should provide 3-5 years warranty.
8. Package
Whatever factory brand or OEM, manufacturer should provide proper stamp (serigraphy), package (carton and box), paper or electronic manual (installation instructions)
How to choose surge protective device SPD manufacturer, These 8 important points of purchasing pluggable surge protective device from China, hope it’s helpful.
We are a family company from and have been supplying surge protection devices (SPD) over the world for more than 10 years. We have our own research & development, production, technical support and testing laboratory as well.
LSP are produced not only for residential and non-residential constructions, but also for industrial applications such as oil pipelines, gas pipelines, photovoltaics, power stations and railways. Our products protect from surge various technologies, machines, appliances and equipment all over the world.
We also develop and manufacture insulation monitoring devices (IMD) for isolated IT power supply networks. We provide a comprehensive, complex A to Z solution for monitoring of insulation status in hospitals, industry and special applications.
We do not pretend that we can do everything, If have any questions and suggestion about SPDs things, our team of skilled technicians will be happy to answer your questions and find the ideal product for you.
