How do I select a proper Prosurge SPD for my application?

Though we try our best to offer an extensive, thorough product presentation on our website, catalogs and other documents, we believe the best way for model selecting is to consult with us with your requirement and then our professional will recommend a suitable model.

What are ANSI/UL 1449 Third Edition Versus IEC 61643-1 – Key Differences In Testing

The following examines a few of the key differences between Underwriters Laboratory’s required test for surge protective devices (SPDs); ANSI/UL 1449 Third Edition and the International Electrotechnical Commission (IEC) required test for SPDs, IEC 61643-1. Short Circuit Current Rating (SCCR): The capacity of current with which the tested SPD can withstand at the terminals where connected, without breaching the enclosure in any way. UL: Tests the full product at twice the nominal voltage to see if entire product is completely offline. The entire product (as shipped) is tested; including metal oxide varistors (MOVs). IEC: Test only looks at the terminals and the physical connections to determine if they are robust enough to handle the fault. MOVs are replaced with a copper block and a manufacturer’s recommended fuse is placed in-line (external to the device). Imax: Per IEC 61643-1 – The crest value of a current through the SPD having an 8/20 waveshape and magnitude according to the test sequence of the class II operating duty test. UL: Does not recognize the need for an Imax test. IEC: An operating duty cycle test is used to ramp up to an Imax point (determined by the manufacturer). This is meant to find “blind points” within the design when subjected to a high level impulse. This is conducted as a life expectancy or robustness test. The fuse needs to withstand Imax, and the test checks thermal stability of the SPD (after each duty cycle impulse bringing the SPD up to its maximum continuous operating voltage MCOV) and its physical condition。 I nominal: The crest value of the current through the SPD having a current waveshape of 8/20. UL: I nominal test is similar to the IEC’s, however, the I nominal results do not link to a Up value (a value used internationally for electrical coordination). Instead, UL uses I nominal to determine a product’s Voltage Protection Rating (VPR). Levels are limited to a maximum of 20 kA. The SPD remains functional after 15 surges. IEC: Does not limit I nominal testing to 20kA, however, the manufacturer’s selected In level is used to get a Up value, a value considered to be the protective performance of the SPD. This value is used for electrical coordination(ratings of building wire, equipment). Therefore the goal of the manufacturer is to try to attain the highest Inominal level with the lowest Up results. Many manufactures opt to only test as high as 20 kA so they will appear to have a low Up. Class versus category UL: UL Type designation is a location designator with a difference to the way I nominal is tested (for device which provides SCCR needs to be included and survive when doing I nominal testing). IEC: Designates certain tests as a class I, II, or III. Class designation between I and II has to do with the impulse applied – Class I; an I imp test (10×350) and a class II – 8 x 20 μs. The IEC designates certain tests as a class I, II, or III and can beconfused with UL’s Type I, II, III, or IV designations. There is some validity to both identifying the product’s approved installation location (UL) and applying a more robust impulse/waveform to those products that will be installed in harsher locations (IEC). Waveforms: A graph of an impulse wave that shows its shape and changes in amplitude with time. UL: Recognizes the 8 x 20 μs waveform. IEC: The IEC incorporates 2 waveforms into their test, the 8 x 20 μs which is used for class II testing to represent surges induced onto power lines. And the 10 x 350 μs waveform which is used for class I testing that represents partial or direct lightning currents (due to building or power line strikes).The IEC also uses other ring wave type waveforms for point of use (class III) tests.

How do I know which is the correct surge protection device that must be installed?

Choosing the right surge arrester(s) is a key factor to guarantee correct protection of the installation. A poorly designed Lightning & Surge protection system may lead to early ageing of the SPD and potential failure of the protective devices in the installation allowing damage to the primary systems up stream, thus defeating the rationale behind the protection being installed Prosurge does not provide a set of rules and guides to support acorrect design of the protection system according to the application. However we follow the IEC and UL lightning and surge protection standards. With this in mind we provide a cascaded system as laid down in the rules of the standard, not the rules of Prosurge. In the field of industrial applications, a standard practice is to install a cascaded protection system based on several coordinated protective devices installed at different stages (LPZ’s). The benefit of this strategy is the fact that it allows a high discharge capacity close to the installation entrance along with a low residual voltage (level of protection) at the main incomer of installation of sensitive equipment. The design of such a protective system is, amongst other factors, based on the assessment of information such as existence of a lightning rod (Lightning Protection System) and type of incoming power supply lines, secondary primary equipment and data systems. The solutions provide protection against either Transient or Permanent (TOV) overvoltages or against both of them (T+P) simultaneously. The final product choice depends on parameters such as: type of installation, type of network disconnection (operation on MCB or RCD), auto reclosing, breaking capacity, etc. Usually you can refer IEC61643- Low-voltage surge protective devices – Part 12:Surge protective devices connected to low-voltage power distribution systems -Selection and application principles

Can lightning destroy the photovoltaic system?

Photovoltaic systems are technologically highly sensitive and a direct lightning strike would definitely destroy it. There is also yet another hazard,as a lightning strike could create surge voltage near the solar power system and these surge voltages can also destroy the system. The inverter is the primary point in need of protection. Usually, inverters will integrate surge-voltage protectors into their inverters. However, since these components only discharge small voltage peaks, you should consider using surge protective devices (SPD) in individual cases.

Are joule ratings a specification used for SPD?

In the past, some manufacturers have used joule ratings in their specifications. They are not considered a good indicator for SPD performance and not recognized by any standard organizations. Prosurge doesn’t support this specification also.

Is “Response Time”a valid specification?

Response time specifications are not supported by any standards organizations overseeing Surge Protective Devices.IEEE C62.62 Standard Test Specification for SPDs specifically mentions it should not be used as a specification.

What are the different power systems in use in the US and what are the protection needs for each?

The US power distribution system is a TN-C-S system. This implies that the Neutral and Ground conductors are bonded at the service entrance of each, and every, facility or separately derived sub-system. This means that the neutral-to-ground (N-G) protection mode within a multi-mode SPD installed at the service entrance panel is basically redundant. Further from this N-G bondpoint, such as in branch distribution panels, the need for this additional mode of protection is more warranted. In addition to the N-G protection mode, some SPDs can include line-to-neutral (L-N) and line-to-line (L-L) protection. On a three phase WYE system, the need for L-L protection is questionable as balanced L-N protection also provides a measure of protection on the L-L conductors. Changes to the 2002 edition of the National Electrical Code® (NEC®) (www.nfpa.org) have precluded the use of SPDs on ungrounded delta power distribution systems. Behind this rather broad statement is the intention that SPDs should not be connected L-G as by so doing these modes of protection are creating pseudo grounds to the floating system. Modes of protection connected L-L are however acceptable.The high-leg delta system is a grounded system and as such allows for protection modes to be connected L-L and L-N or L-G.

How does installation affect the performance of SPDs?

The installation of SPDs is often poorly understood. A good SPD, incorrectly installed, can prove of little benefit in real-life surge conditions. The very high rate-of-change of current, typical of a surge transient, will develop significant volt drops on the leads connecting the SPD to the panel or equipment being protected. This can mean higher than desired voltages reaching the equipment during such a surge condition. Prosurge suggests that measures to counteract this effect include locating the SPD so as to keep interconnecting lead lengths as short as possible, twisting these leads together. Using a heavier gauge AWG cable helps to some extent but this is only a second order effect. It is also important to keep protected and unprotected circuits and leads separate to avoid cross coupling of transient energy.

What is a practical surge rating for service entrance protection?

This is a difficult question and depends on many aspects including – site exposure, regional is okeraunic levels and utility supply. A statistical study of lightning strike probability reveals that the average lightning discharge is between 30 and 40kA, while only 10% of lightning discharges exceed 100kA. Given that a strike to a transmission feeder is likely to share the total current received into anumber of distribution paths, the reality of the surge current entering a facility can be very much less than that of the lightning strike which precipitate it. The ANSI/IEEE C62.41.1-2002 standard seeks to characterize the electrical environment at different locations throughout a facility. It defines the service entrance location as between a B and C environment, meaning that surge currents up to 10kA 8/20 can be experienced in such locations. This said,SPDs located in such environments are often rated above such levels to provide a suitable operating life expectancy, 100kA/phase being typical.

What are surges transients, and temporary over-voltages, and what are their typical characteristics?

Although often used as separate terms in the surge industry, Transients and Surges are the same phenomenon. Transients and Surges can be current, voltage, or both and can have peak values in excess of 10kA or 10kV. They are typically of very short duration (usually >10 µs & <1 ms), with a waveform that has a very rapid rise to the peak and then falls off at a much slower rate. Transients and Surges can be caused by external sources such as lightning or a short circuit, or from internal sources such as Contactor switching, Variable Speed Drives, Capacitor switching, etc. Temporary over voltages (TOVs) are oscillatory phase-to-ground or phase-to-phase over voltages that can last as little as a few seconds or as long as several minutes. Sources of TOV’s include fault reclosing, load switching, ground impedance shifts,single-phase faults and ferroresonance effects to name a few. Due to their potentially high voltage and long duration, TOV’s can be very detrimental to MOV-based SPD’s. An extended TOV can cause permanent damage to an SPD and render the unit inoperable. Note that while UL 1449 (3rd Edition) ensures that the SPD will not create a safety hazard under these conditions, SPDs are not designed to protect against TOVs.

Do SPDs protect against direct lightning strikes?

A direct lighting strike is the most powerful and difficult surge to protect against. Prosurge recommend that Proper grounding and bonding of the electrical system and employing proper surge protection can protect sensitive equipment. A SPD with a higher single surge current rating will perform best against this type of event, if the unit is properly installed and the grounding system is adequate.The maximum single withstand surge current rating is defined in IEEE SPD Standard C62.62.

What is Suppressed Voltage Rating (SVR) and Voltage Protection Rating (VPR)?

SVR was part of an earlier version of UL 1449 Edition and is no longer used in the UL 1449 standard. The SVR was replaced by VPR. VPR is part of the UL 1449 3rd Edition and is the clamping performance data for SPDs. Each SPD mode is subjected to a 6kV/3kA combination surge wave and its measured clamping value is rounded up to the nearest value based on table 63.1 from UL 1449 3rd Edition.

How are SPDs related to UL 96A?

UL 96A is the standard for Lightning Protection systems. For a building to meet UL 96A is must have a Type 1 SPD with a Nominal Discharge Current rating of 20kA installed at the service entrance.

How does a Type 1 SPD compare to a Type 2 SPD?

Some key differences between Type 1 and Type 2 SPDs are: External Overcurrent Protection. Type 2 SPDs may require external overcurrent protection or it may be included within the SPD. Type 1 SPDs generally include overcurrent protection within the SPD or other means to satisfy the requirements of the standard; thus, Type 1 SPDs and Type 2 SPDs that do not require external overcurrent protection devices eliminate the potential for installing an incorrectly rated (mismatched) overcurrent protection device with the SPD. Nominal Discharge Current Ratings. Available Nominal Discharge Current (In) ratings of Type 1 SPDs are 10 kA or 20 kA; whereas, Type 2 SPDs may have 3 kA , 5 kA, 10 kA or 20 kA Nominal Discharge Current ratings. UL 1283 EMI/RFI Filtering. Some UL 1449 Listed SPDs include filter circuits that have been evaluated as a UL 1283 (Standard for Electromagnetic Interference Filters) filter. These are complimentary UL Listed as a UL 1283 filter and a UL 1449 SPD. By definition and the scope of UL 1283, UL 1283 Listed filters are evaluated for load-side applications only, not line-side applications. Consequently, UL will not complimentary list a Type 1 SPD as a UL 1283 Listed filter. However, a Type 1 SPD might include a UL 1283 filter as a Recognized Component within a Listed Type 1 SPD, which has been fully evaluated for lineside usage. Manufacturers of such products generally offer the identical SPD as a Type 2 UL 1449 Listed SPD with complimentary Listing as a UL 1283 Listed filter. Capacitors. Capacitors utilized in Type 1 SPDs may be evaluated for safety differently than in Type 2 SPDs. All capacitors in Type 1 SPD applications are evaluated to UL 810 (Standard for Capacitors). This includes filtering capacitors referenced above in UL 1283 (Standard for Electromagnetic Interference Filters) applications. Capacitors in Type 2 SPDs are evaluated to UL 1414 (Standard for Capacitors and Suppressors for Radio- and Television-Type Appliances) and/or UL 1283 (Standard for Electromagnetic Interference Filters).

What are the UL SPD Type categories and what do they mean?

Type 1 SPDs (Listed) – Permanently connected, hard-wired SPDs intended for installation between the secondary of the service transformer and the line side of the main service equipment overcurrent protective device, as well as the load side of the main service equipment (i.e. Type 1’s can be installed anywhere within the distribution system). Type 1 SPDs include watt-hour meter socket enclosure type SPDs. Being on the line side of the service disconnect where there are no overcurrent protective devices to protect an SPD, Type 1 SPDs must be listed without the use of an external overcurrent protective device. The Nominal Discharge Current Rating for Type 1 SPDs is either 10kA or 20kA. Type 2 SPDs (Listed) – Permanently connected, hard-wired SPDs intended for installation on the load side of the main service equipment overcurrent protective device. These SPDs may also be installed at the main service equipment, but must be installed on the load side of the main service overcurrent protective device. Type 2 SPDs may or may not require an overcurrent protection device per their NRTL listing. If a specific overcurrent protection is required, the SPD’s NRTL listing file and labeling/instructions are required to note the size and type of overcurrent protective device. Note: In some cases the overcurrent protective device used can impact the nominal discharge rating of the SPD. For example, the SPD may have a 10 kA nominal discharge current rating when protected by a 30 Amp circuit breaker and a 20 kA nominal discharge current rating when protected by a different but specific make and model of overcurrent protection device. The Nominal Discharge Current Rating for Type 2 SPDs is 3 kA, 5 kA, 10 kA, or 20 kA. Type 3 SPDs (Listed) – These SPDs are called, ‘Point of Utilization SPDs’, which are to be installed at a minimum conductor length of 10 meter (30 feet) from the electrical service panel unless they are evaluated at Type 2 SPDs (that is, they receive a Nominal Discharge Current Rating of 3 kA minimum). Typically, these are cord-connected surge strips, direct plug-in SPDs, or receptacle-type SPDs installed at the utilization equipment being protected (i.e. computers, copy machines, etc.). Type 1, 2, 3 Component Assembly SPDs (Component Recognized) – These SPDs are intended to be factory installed into electrical distribution equipment or end-use equipment. These are Recognized Component SPDs evaluated for use in Type 1, 2 or 3 SPD applications. Such component SPDs must pass all the same electrical safety failure tests as listed Type 1, 2 or 3 SPDs. While these SPDs are 100% compliant from a safety failure testing point of view, these Type 1, 2 and 3 component assembly SPDs have conditions of acceptability such as exposed terminals or other mechanical construction that requires them to be installed or housed within a listed assembly to provide protection from exposure to live parts or other requirements. These Type 1, 2 or 3 Recognized Component SPDs should not be confused with ANSI/UL 1449-2006 Type 4 Component Assemblies and Type 5 discrete SPD components that require additional components (possibly safety disconnectors), design and testing in order to be used as a complete surge protective device. Type 4 Component Assembly SPD (Component Recognized) –– These component assemblies consist of one or more Type 5 SPD components together with a disconnector (integral or external) or a means of complying with the limited current tests in UL 1449, Section 39.4. These are incomplete SPD assemblies, which typically are installed in listed end-use products as long as all conditions of acceptability are met. These Type 4 component assemblies are incomplete as an SPD, require further evaluation and are not permitted to be installed in the field as a stand-alone SPD. Often, these devices require additional overcurrent protection. Type 5 SPD (Component Recognized) – Discrete component surge protection devices, such as MOVs that may be mounted on a printed wiring board, connected by its leads or provided within an enclosure with mounting means and wiring terminations. These Type 5 SPD components are incomplete as an SPD, require further evaluation and are not permitted to be installed in the field as a stand-alone SPD. Type 5 SPDs are generally the components used in the design and construction of complete SPDs or other SPD assemblies.

What is the UL Short Circuit Current Rating (SCCR)?

SSCR-Short Circuit Current Rating. The suitability of an SPD for use on an AC power circuit that is capable of delivering not more than a declared rms symmetrical current at a declared voltage during a short circuit condition. SCCR is not the same as AIC (Amp Interrupting Capacity). SCCR is the amount of “available”current that the SPD can be subjected to and safely disconnect from the power source under short circuit conditions. The amount of current “interrupted” by the SPD is typically significantly less than the “available” current. UL 1449 and the National Electric Code (NEC) require the SCCR (Short Circuit Current Rating) to be marked on all SPD units. It is not a surge rating, but the maximum allowable current a SPD can interrupt in the event of failure. The NEC/UL has a requirement that the SPD be tested and labelled with a SCCR equal to, or greater than the available fault current at that point in the system.

What is important when specifying SPD?

When specifying SPD, submit a clear, concise specification detailing the required performance and design features. A minimum specification should include: • UL surge rating • Suppression rating • Short circuit rating • Peak surge current per mode (L-N, L-G, and N-G) • voltage and configuration of electrical service

What is a Surge Protective Device or Surge Arrestor (SPD)?

SPD is a device designed to limit surge energy to electrical equipment. It does this by diverting or limiting surge current. An SPD is wired in parallel to the equipment it is intended to protect. Once the surge voltage exceeds its designed rating it “begins to clamp” and starts to conduct energy directly to the electrical grounding system. An SPD has a very low resistance during this time and “shorts” the energy to ground. Once the surge is over it “opens” up, so it does not trigger upstream circuit breakers.

FAQ - Prosurge

Q: Do SPDs protect against direct lightning strikes?

A direct lighting strike is the most powerful and difficult surge to protect against. Prosurge recommend that Proper grounding and bonding of the electrical system and employing proper surge protection can protect sensitive equipment. A SPD with a higher single surge current rating will perform best against this type of event, if the unit is properly installed and the grounding system is adequate.The maximum single withstand surge current rating is defined in IEEE SPD Standard C62.62.

Kuv yuav ua li cas xaiv Xaiv Tsa SPD rau kuv daim ntawv thov?ntiav2017-10-31T17:34:33+08:00

Kuv yuav ua li cas xaiv Xaiv Tsa SPD rau kuv daim ntawv thov?

Txawm hais tias peb sim ua qhov zoo tshaj plaws los muab cov kev nthuav qhia nthuav dav rau peb lub vev xaib, cov ntawv teev lus thiab lwm cov ntaub ntawv, peb ntseeg tias qhov zoo tshaj plaws rau kev xaiv cov qauv yog tuaj sab laj nrog peb cov lus samfwm thiab ces peb cov neeg yuav pom zoo kom tsim qauv.

Dab tsi yog ANSI / UL 1449 Third Edition Versus IEC 61643-1 - Qhov Tseem Ceeb Hauv Kev Xeemntiav2017-10-31T17:29:56+08:00

Dab tsi yog ANSI / UL 1449 Third Edition Versus IEC 61643-1 - Qhov Tseem Ceeb Hauv Kev Xeem

Cov hauv qab no tshuaj xyuas ob peb qhov sib txawv tseem ceeb ntawm Underwriters Laboratory qhov yuav tsum tau kuaj rau cov khoom siv tiv thaiv kev kub ntxhov (SPDs); ANSI / UL 1449 Thib Peb thiab International Electrotechnical Commission (IEC) xav tau kev xeem rau SPDs, IEC 61643-1.

Short Circuit Current Rating (SCCR): Lub peev xwm ntawm qhov tam sim no uas tau sim SPD tuaj yeem tiv taus ntawm cov terminals uas txuas nrog, yam tsis muaj kev ua txhaum cai ntawm lub qhov rooj.

UL: Ntsuas tag nrho cov khoom ntawm ob zaug lub nominal voltage kom pom tias tag nrho cov khoom yog offline kiag li. Tag nrho cov khoom (raws li xa khoom) raug kuaj; suav nrog hlau oxide varistors (MOVs).

IEC: Kev ntsuam xyuas tsuas yog saib ntawm lub davhlau ya nyob twg thiab lub cev sib txuas los txiav txim siab seb lawv puas muaj peev xwm los daws qhov txhaum. MOVs raug hloov nrog lub thaiv tooj liab thiab cov chaw tsim khoom pom zoo fuse yog muab tso rau hauv kab (sab nraud rau lub cuab yeej).

Imax: Ib IEC 61643-1 - Tus nqi ntawm qhov tam sim no los ntawm SPD muaj 8/20 waveshape thiab magnitude raws li kev xeem ua ntu zus ntawm chav kawm II kev ua haujlwm ua haujlwm.

UL: Tsis lees paub qhov xav tau rau kev xeem Imax.

IEC: Kev ntsuas lub luag haujlwm ua haujlwm yog siv los nce mus txog qhov taw tes Imax (txiav txim siab los ntawm cov chaw tsim khoom). Qhov no txhais tau tias kom pom "cov ntsiab lus dig muag" nyob rau hauv tus qauv tsim thaum raug rau qib siab impulse. Qhov no yog ua raws li lub neej expectancy los yog robustness test. Lub fuse yuav tsum tau tiv thaiv Imax, thiab qhov kev kuaj xyuas thermal stability ntawm SPD (tom qab txhua lub luag hauj lwm lub voj voog impulse coj SPD mus rau nws qhov siab tshaj plaws kev khiav hauj lwm voltage MCOV) thiab nws lub cev mob.

Kuv nominal: Tus nqi crest ntawm qhov tam sim no los ntawm SPD muaj qhov tam sim no waveshape ntawm 8/20.

UL: Kuv qhov kev xeem nominal zoo ib yam li IEC's, txawm li cas los xij, qhov txiaj ntsig kuv nominal tsis txuas rau tus nqi nce (tus nqi siv thoob ntiaj teb rau kev sib koom ua hluav taws xob). Hloov chaw, UL siv I nominal los txiav txim qhov khoom tiv thaiv qhov ntsuas hluav taws xob (VPR). Cov qib raug txwv rau qhov siab tshaj plaws ntawm 20 kA. SPD tseem ua haujlwm tom qab 15 surges.

IEC: Tsis txwv kuv qhov kev sim nominal rau 20kA, txawm li cas los xij, cov chaw tsim khoom xaiv hauv qib yog siv kom tau txais tus nqi nce, tus nqi suav tias yog kev tiv thaiv kev ua haujlwm ntawm SPD. Tus nqi no yog siv rau kev sib koom ua hluav taws xob (kev ntsuas ntawm lub tsev hlau, khoom siv).

Yog li lub hom phiaj ntawm cov chaw tsim khoom yog sim kom ua tiav qhov siab tshaj plaws Inominal theem nrog qhov qis tshaj Up tau. Ntau qhov chaw tsim khoom xaiv tsuas yog ntsuas siab li 20 kA yog li lawv yuav tshwm sim kom muaj qhov qis qis.

Chav kawm tiv tiag

UL: UL hom kev xaiv yog tus tsim qhov chaw nrog qhov sib txawv ntawm txoj kev kuv nominal raug kuaj (rau cov cuab yeej uas muab SCCR yuav tsum tau suav nrog thiab muaj sia nyob thaum ua kuv xeem nominal).

IEC: Tsim qee qhov kev xeem raws li chav kawm I, II, lossis III. Kev xaiv chav kawm ntawm I thiab II yuav tsum ua nrog rau qhov kev xav tau - Chav I; ib qho kev xeem I imp (10 × 350) thiab chav kawm II - 8 x 20 μs.

Lub IEC tau xaiv qee qhov kev ntsuam xyuas ua ib hoob I, II, lossis III thiab tuaj yeem tsim tau UL tus Hom I, II, III, lossis IV. Muaj qee qhov tseem ceeb rau ob qho tib si txheeb xyuas qhov chaw tsim nyog qhov chaw nruab (UL) thiab thov kom muaj kev ruaj siab ntxiv / yawm suab rau cov khoom uas yuav muab tso rau hauv qhov chaw harsher (IEC).

Waveforms: Ib daim duab ntawm lub zog nthwv dej uas qhia nws cov duab thiab kev hloov pauv hauv amplitude nrog lub sijhawm.

UL: Pom qhov 8 x 20 μs waveform.

IEC: Lub IEC suav nrog 2 waveforms rau hauv lawv qhov kev sim, 8 x 20 μs uas yog siv rau hauv chav kawm II kuaj los sawv cev rau kev nce siab hauv cov kab hluav taws xob. Thiab 10 x 350 μs waveform uas yog siv rau hauv chav kawm I kuaj uas sawv cev rau ib feem lossis ncaj qha hluav taws xob tam sim no (vim lub tsev lossis lub zog hluav taws xob tawm tsam).IEC kuj tseem siv lwm lub nplhaib nthwv dej hom waveforms rau kev siv (chav kawm III) kev xeem.

Yuav ua li cas kuv thiaj paub qhov twg yog qhov tseeb surge tiv thaiv ntaus ntawv uas yuav tsum tau ntsia?ntiav2017-10-31T17:28:05+08:00

Yuav ua li cas kuv thiaj paub qhov twg yog qhov tseeb surge tiv thaiv ntaus ntawv uas yuav tsum tau ntsia?

Xaiv txoj cai surge arrester (s) yog ib qho tseem ceeb los lav qhov tseeb kev tiv thaiv ntawm lub installation. Lub teeb pom kev tsis zoo tsim hluav taws xob & Kev tiv thaiv hluav taws xob tuaj yeem ua rau muaj kev laus thaum ntxov ntawm SPD thiab muaj peev xwm ua tsis tiav ntawm cov cuab yeej tiv thaiv hauv kev teeb tsa uas tso cai rau kev puas tsuaj rau thawj cov kab ke nce kwj, yog li kov yeej qhov laj thawj tom qab kev tiv thaiv raug teeb tsa.

Tawm tswv yim tsis muab ib co kev cai thiab cov txheej txheem los txhawb kev tsim kho cov kev tiv thaiv raws li daim ntawv thov. Txawm li cas los xij peb ua raws li IEC thiab UL hluav taws xob thiab kev tiv thaiv kev tiv thaiv. Nrog rau qhov no hauv siab peb muab lub kaw lus cascaded li nteg nyob rau hauv cov kev cai ntawm tus qauv, tsis cov cai ntawm Prosurge.

Hauv daim teb ntawm daim ntaub ntawv siv, ib qho kev xyaum ua haujlwm yog los nruab ib qhov kev tiv thaiv kab ke cascaded raws li ob peb cov kev tiv thaiv kab mob nruab rau hauv ntau theem (LPZ's). Cov txiaj ntsig ntawm qhov no yog qhov tseeb tias nws tso cai rau cov neeg ua haujlwm siab ze ntawm qhov kev nkag ntawm qhov kev nkag teeb nrog nrog qhov seem uas tsis muaj qhov seem (kev tiv thaiv) ntawm lub ntsiab ntawm lub tshuab hluav taws xob.

Tus qauv tsim ntawm qhov kev tiv thaiv no yog, nrog rau lwm yam, raws li kev txheeb xyuas cov ntaub ntawv xws li lub neej muaj hluav taws xob (Lightning Protection System) thiab hom kev xa khoom hluav taws xob, cov khoom siv thib ob thiab cov ntaub ntawv tshuab.

Cov kev daws teebmeem kev tiv thaiv ntawm Transient lossis Permanent (TOV) overvoltages los yog ob leeg ntawm lawv (T + P) ib txhij.

Qhov khoom kawg ntawm kev xaiv nyob ntawm tsis xws li: hom installation, hom kev tshem tawm hauv lub lag luam (kev ua lag luam ntawm MCB los yog RCD), pib rov, txhawm rau, thiab lwm yam.

Feem ntau koj tuaj yeem xa IEC61643- Cov khoom siv tiv thaiv hluav taws xob qis - Ntu 12: Cov khoom tiv thaiv hluav taws xob txuas nrog cov hluav taws xob faib hluav taws xob tsawg-Xaiv thiab cov qauv siv

Ua hluav taws xob ua puas lub photovoltaic system?ntiav2017-10-31T17:26:31+08:00

Ua hluav taws xob ua puas lub photovoltaic system?

Photovoltaic systems yog cov cuabyeej rhiab heev thiab lub sijhawm siv hluavtaws xob twv twv yuav raug rhuav tshem nws. Kuj tseem muaj lwm txoj hauv kev nyab xeeb, raws li lub zog tho tawm tuaj yeem ua kom muaj qhov tsis muaj zog nyob ze ntawm lub hnub ci zog thiab cov kev ua haujlwm tsis txaus siab no kuj ua rau lub cev puas lawm. Tus inverter yog thawj qhov chaw xav tau kev tiv thaiv. Feem ntau, cov neeg hloov rog yuav nkag mus rau cov neeg tiv thaiv kev ruaj ntseg mus rau hauv lawv cov inverters. Txawm li cas los xij, vim cov khoom no tsuas yog tso tawm qhov me me voltage peaks, koj yuav tsum xav txog kev siv cov khoom tiv thaiv kom tsis txhob muaj kev tiv thaiv (SPD) rau hauv tus neeg mob.

Puas yog joule kev siv cov lus qhia siv rau SPD?ntiav2017-10-31T17:25:41+08:00

Puas yog joule kev siv cov lus qhia siv rau SPD?

Nyob rau hauv lub dhau los, ib co manufacturers tau siv joule kev nyob rau hauv lawv cov specifications. Lawv tsis yog ib qho kev qhia zoo rau SPD qhov kev ua tau zoo thiab tsis lees paub los ntawm tej pawg neeg sawv cev. Prosecutory tsis txhawb qhov kev qhia tshwj xeeb no.

Puas yog "Lub Sijhawm Tawm Tsam" ib qhov kev qhia tawm tau?ntiav2017-10-31T17:24:47+08:00

Puas yog "Lub Sijhawm Tawm Tsam" ib qhov kev qhia tawm tau?

Cov lus teb rau lub sijhawm tsis muaj kev txhawb nqa los ntawm tej pawg neeg tswj hwm kev tswj xyuas Cov Kev Tiv Thaiv Cov Ntaus Nqi CEEV THIAJ C62.62 Standard Test rau SPDs tshwj xeeb tshaj tawm hais tias yuav tsum tsis txhob siv raws li cov lus qhia.

Dab tsi yog cov tshuab hluav taws xob sib txawv hauv kev siv hauv Asmeskas thiab dab tsi yog qhov kev tiv thaiv xav tau rau txhua tus?ntiav2017-10-31T17:23:39+08:00

Dab tsi yog cov tshuab hluav taws xob sib txawv hauv kev siv hauv Asmeskas thiab dab tsi yog qhov kev tiv thaiv xav tau rau txhua tus?

Tebchaws Asmeskas fais fab kev lag luam yog lub TN-CS system. Qhov no txhais tau hais tias Cov Neeg Hluav Taws Xob thiab Cov Neeg Tsav Nkeeg sib raug zoo ntawm qhov kev nkag mus nkag ntawm txhua qhov, thiab txhua qhov chaw los yog qhov chaw cais tawm. Qhov no txhais tau hais tias qhov nruab nrab-rau-av (NG) tiv thaiv hom nyob rau hauv ntau hom SPD ntsia rau ntawm qhov kev pab cuam nkag ntawm qhov kev nkag teb chaws yog rov ua dua. Txuas ntxiv los ntawm qhov nyiaj hauv NG, xws li hauv cov chaw faib khoom faib, kev xav tau rau hom kev tiv thaiv ntxiv no muaj ntau dua. Ntxiv rau NG tiv thaiv hom, qee qhov SPDs muaj xws li kab-rau-nruab nrab (LN) thiab kab-rau-kab (LL) tiv thaiv. Nyob rau peb theem WYE system, qhov kev xav tau rau kev tiv thaiv LL yog questionable li balanced LN tiv thaiv kuj muab ib qho kev ntsuas ntawm kev tiv thaiv ntawm cov neeg tsav tsheb LL.
Cov kev hloov rau 2002 tsab ntawm National Electrical Code® (NEC®) (www.nfpa.org) tau siv cov SPDs ntawm cov cuab yeej tawm hauv lub cev uas tsis muaj vaj huam sib luag. Tom qab daim ntawv no nthuav dav yog lub hom phiaj uas SPDs yuav tsum tsis txhob cuam tshuam nrog LG raws li yog li ua cov hom kev tiv thaiv no tsim cov pseudo qhov chaw mus rau hauv lub tshuab floating. Hom kev tiv thaiv ntawm kev tiv thaiv LL tau li cas los xij. Qhov kev sib txuas ntawm cov taw kev siab tshaj plaws yog lub hauv paus thiab raws li kev tso cai rau kev tiv thaiv hom kev txuas nrog LL thiab LN lossis LG.

Yuav ua li cas installation thiaj cuam tshuam rau kev ua haujlwm ntawm SPDs?ntiav2017-10-31T17:19:51+08:00

Yuav ua li cas installation thiaj cuam tshuam rau kev ua haujlwm ntawm SPDs?

Lub installation ntawm SPDs feem ntau tsis zoo to taub. Ib qho zoo SPD, incorrectly ntsia, tuaj yeem ua pov thawj ntawm cov txiaj ntsim kev pab me ntsis hauv lub neej tiag tiag. Qhov siab heev ntawm kev hloov ntawm kev hloov tam sim no, yuav ua rau lub caij ntheev, yuav tsim teeb meem ntawm cov hluav taws xob tsawg los ntawm kev ua txuas nrog SPD rau lub vaj huam sib luag lossis cov khoom siv tiv thaiv. Qhov no tuaj yeem txhais tau siab siab tshaj qhov xav tau ntawm cov khoom hluav taws xob kom ncav cuag lub cuab yeej thaum lub sij hawm zoo li no. Tus txheejtxheem pom tias cov kev ntsuas los cuam tshuam cov txiaj ntsig no suav nrog SPD txhawm rau kom sib txuas kav ntev li ntev li sai tau, kev sib tw ua ke ua ke. Siv lub ntsuas pa AWG ntau dua, tiam sis qhov no tsuas yog qhov kev txiav txim thib ob. Nws yog ib qho tseem ceeb kom tsis txhob muaj kev tiv thaiv thiab tsis muaj kev tiv thaiv thiab ua rau kom tsis txhob hla kev ua haujlwm ntawm lub zog.

Dab tsi yog qhov kev nqis tes ua qhov nce siab rau kev pab tiv thaiv kev nkag mus?ntiav2017-10-31T17:17:34+08:00

Dab tsi yog qhov kev nqis tes ua qhov nce siab rau kev pab tiv thaiv kev nkag mus?

Qhov no yog ib lo lus nug nyuaj thiab nyob ntawm ntau yam xws li - qhov chaw raug, thaj chaw nruab nrab ntawm lub regional thiab cov khoom siv hluav taws xob. Ib qho kev kawm ntawm kev tawm dag zog thim tshwm tawm tias qhov nruab nrab xob laim tawm ntawm 30 thiab 40kA, tsuas yog 10% ntawm xob laim tshaj 100kA. Muab hais tias qhov kev tawm tsam mus rau kev sib faib khoom noj yog qhov yuav tsum tau faib tag nrho tam sim no tau txais kev pom zoo ntawm kev faib tawm, qhov tseeb ntawm kev cia siab tam sim no nkag mus rau hauv qhov chaw yuav muaj tsawg dua li qhov kev tsim hluav taws xob uas tsuj nws.

ANSI/IEEE C62.41.1-2002 tus qauv nrhiav kom pom cov hluav taws xob ib puag ncig ntawm qhov chaw sib txawv thoob plaws hauv ib lub chaw. Nws txhais tau hais tias qhov kev pabcuam nkag mus rau qhov chaw nyob nruab nrab ntawm B thiab C ib puag ncig, txhais tau hais tias qhov hluav taws xob nce mus txog 10kA 8/20 tuaj yeem ntsib hauv qhov chaw zoo li no. Qhov no hais tias, SPDs nyob rau hauv xws li ib puag ncig yog feem ntau nyob rau saum toj no theem los muab ib tug tsim nyog lub neej expectancy, 100kA / theem yog ib txwm.

Dab tsi yog surges transients, thiab ib ntus tshaj-voltages, thiab dab tsi yog lawv cov yam ntxwv?ntiav2017-10-31T17:16:14+08:00

Dab tsi yog surges transients, thiab ib ntus tshaj-voltages, thiab dab tsi yog lawv cov yam ntxwv?

Txawm hais tias feem ntau siv los ua cov lus sib cais nyob rau hauv kev lag luam surge, Hloov thiab surges yog qhov tshwm sim zoo ib yam. Cov neeg hloov pauv thiab kub siab tuaj yeem yog qhov tam sim no, voltage, lossis ob qho tib si thiab tuaj yeem muaj cov txiaj ntsig siab kawg hauv kev dhau 10kA lossis 10kV. Lawv feem ntau yog lub sijhawm luv heev (feem ntau> 10 µs & <1 ms), nrog nthwv dej uas muaj qhov nrawm nrawm mus rau qhov kawg thiab tom qab ntawd ntog tawm ntawm ntau qeeb qeeb. Cov neeg hla thiab kev nce siab tuaj yeem tshwm sim los ntawm cov khoom siv sab nraud xws li xob laim lossis luv Circuit Court, lossis los ntawm qhov chaw sab hauv xws li Tus Tawm Hloov Txuas, Tus Cuam Tshuam Ceev, Capacitor hloov, thiab lwm yam.

Ib ntus ntev zog (TOVs) yog cov oscillatory theem-rau-hauv av los yog theem-rau-theem dhau voltages uas yuav kav ntev li ob peb feeb lossis ntev li ob peb feeb. Cov chaw ntawm TOV muaj xws li kev rov qab raug teeb meem, kev thauj khoom hloov, kev hloov hauv av, kev ua yuam sij ib theem thiab cov teeb meem ferroresonance rau cov npe me ntsis. Vim tias lawv muaj qhov siab tshaj qhov muaj zog thiab ntev ntev, TOV's yuav ua rau muaj kev puas tsuaj rau MOV-based SPD's. Tus mob TOV ntev tuaj yeem ua rau kev puas tsuaj mus tas li rau SPD thiab muab lub tsev ua haujlwm tsis raug. Nco ntsoov tias thaum UL 1449 (3rd Edition) xyuas kom meej tias SPD yuav tsis tsim kev nyab xeeb rau hauv cov xwm txheej no, SPDs tsis tsim los tiv thaiv TOVs.

Ua SPDs tiv thaiv kev siv hluav taws xob ncaj qha?ntiav2017-10-31T17:13:42+08:00

Ua SPDs tiv thaiv kev siv hluav taws xob ncaj qha?

Lub teeb pom kev ncaj qha yog qhov tseem ceeb tshaj plaws thiab tsis muaj kev tiv thaiv. Tawm tswv yim pom zoo tias Kev sib haum thiab kev sib txuas ntawm lub qhov hluav taws xob thiab kev tiv thaiv kom muaj kev tiv thaiv zoo tuaj yeem tiv thaiv cov khoom siv cuab yeej. Lub SPD uas muaj ntau tshaj qhov kev ntsuam xyuas tam sim no yuav ua qhov zoo tshaj plaws tiv thaiv hom kev tshwm sim no, yog hais tias lub tsev raug txhim kho thiab qhov av zoo tsim nyog.Qhov siab tshaj plaws uas tsis muaj kev tiv thaiv tam sim no sau tseg hauv IEEE SPD Standard C62.62.

Dab tsi yog Suppressed Voltage Rating (SVR) thiab Voltage Protection Rating (VPR)?ntiav2017-10-31T17:10:31+08:00

Dab tsi yog Suppressed Voltage Rating (SVR) thiab Voltage Protection Rating (VPR)?

SVR yog ib feem ntawm ib qho kev ua ntej UL 1449 tsab thiab tsis siv nyob hauv UL 1449 txuj. Lub SVR tau hloov los ntawm VPR.

VPR yog ib feem ntawm UL 1449 3rd Edition thiab yog qhov clamping performance data rau SPDs. Txhua SPD hom yog raug 6kV / 3kA ua ke tshuav nthwv dej thiab nws cov ntsuas clamping yog sib npaug mus rau qhov nqi uas ze tshaj plaws raws li cov lus 63.1 ntawm UL 1449 3rd Edition.

Cov SPDs muaj feem rau UL 96A li cas?ntiav2017-10-31T17:05:54+08:00

Cov SPDs muaj feem rau UL 96A li cas?

UL 96A yog tus qauv rau xob tshuab. Rau ib lub tsev mus ntsib UL 96A yuav tsum muaj ib hom 1 SPD nrog lub Nominal Discharge Tam sim no kev ntsuam xyuas ntawm 20kA ntsia ntawm qhov kev pab nkag.

Ib hom 1 SPD piv rau ib hom 2 SPD li cas?ntiav2017-10-31T17:01:51+08:00

Ib hom 1 SPD piv rau ib hom 2 SPD li cas?

Qee qhov tseem ceeb sib txawv ntawm hom 1 thiab Hom 2 SPDs yog:

Sab nraud Overcurrent Protection. Hom 2 SPDs tuaj yeem xav tau sab nraud overcurrent
kev tiv thaiv lossis nws tuaj yeem suav nrog hauv SPD. Hom 1 SPDs feem ntau suav nrog
Kev tiv thaiv overcurrent hauv SPD lossis lwm yam txhais tau tias kom ua tau raws li qhov yuav tsum tau ua
ntawm tus qauv; Yog li, Hom 1 SPDs thiab Hom 2 SPDs uas tsis xav tau sab nraud
cov cuab yeej tiv thaiv overcurrent tshem tawm cov peev xwm rau kev txhim kho qhov tsis raug
rated (mismatched) overcurrent tiv thaiv ntaus ntawv nrog SPD.
Nominal Discharge Current Ratings. Muaj Nominal Discharge Current (In)
Kev ntsuas ntawm Hom 1 SPDs yog 10 kA lossis 20 kA; whereas, Hom 2 SPDs yuav muaj 3
kA, 5 kA, 10 kA lossis 20 kA Nominal Discharge Current ratings.
UL 1283 EMI / RFI lim. Qee qhov UL 1449 Sau SPDs suav nrog cov lim dej
uas tau raug soj ntsuam raws li UL 1283 (Standard for Electromagnetic Interference
Filter) cov. Cov no yog pub dawb UL Sau npe raws li UL 1283 lim thiab UL
1449 PAB. Los ntawm cov ntsiab lus thiab cov peev txheej ntawm UL 1283, UL 1283 Cov ntawv teev npe yog
ntsuas rau load-sab daim ntawv thov nkaus xwb, tsis yog kab-sab daim ntawv thov.
Yog li ntawd, UL yuav tsis pub sau npe rau Hom 1 SPD raws li UL 1283 Sau
lim. Txawm li cas los xij, Hom 1 SPD tuaj yeem suav nrog UL 1283 lim raws li Kev Pom Zoo
Cov khoom siv nyob rau hauv Daim Ntawv Teev Npe 1 SPD, uas tau raug soj ntsuam tag nrho rau kab
kev siv. Cov neeg tsim khoom ntawm cov khoom zoo li no feem ntau muab cov SPD zoo ib yam li ib
Hom 2 UL 1449 Sau SPD nrog Daim Ntawv Teev Npe pub dawb raws li UL 1283 Sau
lim.
Capacitors. Capacitors siv hauv Hom 1 SPDs tuaj yeem raug soj ntsuam rau kev nyab xeeb
txawv ntawm hom 2 SPDs. Tag nrho cov capacitors hauv hom 1 SPD daim ntawv thov yog
Kev ntsuas rau UL 810 (Standard for Capacitors). Qhov no suav nrog filtering capacitor
hais saum toj no hauv UL 1283 (Standard for Electromagnetic Interference Filters)
daim ntawv thov. Capacitors hauv Hom 2 SPDs raug soj ntsuam rau UL 1414 (Standard for
Capacitors thiab Suppressors rau Xov Tooj Cua- thiab TV-Type Appliances) thiab/los yog
UL 1283 (Standard for Electromagnetic Interference Filters).

UL SPD Hom Pawg yog dab tsi thiab lawv txhais li cas?ntiav2017-10-31T16:58:48+08:00

UL SPD Hom Pawg yog dab tsi thiab lawv txhais li cas?

Hom 1 SPDs (Sau npe) - Txuas mus tas li, nyuaj-wired SPDs npaj rau
installation ntawm theem nrab ntawm qhov kev pab cuam transformer thiab kab sab ntawm lub ntsiab
cov khoom siv kev pabcuam overcurrent tiv thaiv ntaus ntawv, nrog rau lub load sab ntawm lub ntsiab
cov khoom siv (xws li Hom 1's tuaj yeem ntsia tau rau txhua qhov chaw hauv kev faib khoom
system). Hom 1 SPDs suav nrog watt-teev meter socket enclosure hom SPDs. Ua rau ntawm
kab sab ntawm cov kev pab cuam disconnect qhov twg tsis muaj overcurrent tiv thaiv pab kiag li lawm
tiv thaiv ib qho SPD, Hom 1 SPDs yuav tsum tau teev tseg yam tsis muaj kev siv sab nraud overcurrent
ntaus ntawv tiv thaiv. Qhov Nominal Discharge Current Rating rau Hom 1 SPDs yog ob qho tib si
10kA lossis 20kA.

Hom 2 SPDs (Sau npe) - Txuas mus tas li, nyuaj-wired SPDs npaj rau
installation ntawm lub load sab ntawm lub ntsiab kev pab cuam khoom overcurrent tiv thaiv ntaus ntawv.
Cov SPDs no kuj yuav raug ntsia rau ntawm cov khoom siv tseem ceeb, tab sis yuav tsum tau muab tso rau
lub load sab ntawm lub ntsiab kev pab cuam overcurrent tiv thaiv ntaus ntawv. Hom 2 SPDs tej zaum yuav los yog tej zaum
tsis tas yuav muaj cov cuab yeej tiv thaiv overcurrent rau lawv cov npe NRTL. Yog ib qho tshwj xeeb
Kev tiv thaiv overcurrent yog yuav tsum tau, SPD's NRTL cov ntaub ntawv teev npe thiab sau npe / cov lus qhia
yuav tsum nco ntsoov qhov loj thiab hom ntawm overcurrent tiv thaiv ntaus ntawv. Lus Cim: Hauv qee qhov
rooj plaub uas siv cov khoom siv tiv thaiv overcurrent tuaj yeem cuam tshuam rau qhov kev ntsuas nominal tawm ntawm
lub SPD. Piv txwv li, SPD yuav muaj 10 kA nominal tso tawm tam sim no ntsuas
thaum tiv thaiv los ntawm 30 Amp Circuit Court breaker thiab 20 kA nominal tawm tam sim no
ntsuam xyuas thaum tiv thaiv los ntawm qhov sib txawv tab sis tshwj xeeb ua thiab qauv ntawm overcurrent
ntaus ntawv tiv thaiv. Qhov Nominal Discharge Tam Sim No Rating rau Hom 2 SPDs yog 3 kA, 5
10 kA, 20 kA.

Hom 3 SPDs (Lus Sau) - Cov SPDs no hu ua, 'Point of Utilization SPDs', uas yog rau
raug ntsia ntawm qhov tsawg kawg nkaus tus neeg xyuas pib qhov ntev ntawm 10 meter (30 ko taw) los ntawm cov hluav taws xob
pab pawg tshwj tsis yog lawv raug soj ntsuam ntawm Hom 2 SPDs (uas yog, lawv tau txais Nominal
Tawm tam sim no ntsuas ntawm 3 kA yam tsawg kawg nkaus). Feem ntau, cov no yog cov kab txuas txuas txuas
strips, direct plug-in SPDs, los yog receptacle-type SPDs ntsia ntawm cov khoom siv
raug tiv thaiv (xws li khoos phis tawj, tshuab luam ntawv, thiab lwm yam).

Hom 1, 2, 3 Component Assembly SPDs (Component Recognized) - Cov SPDs no yog
npaj rau lub Hoobkas ntsia rau hauv cov khoom siv hluav taws xob xa hluav taws xob lossis kev siv kawg
khoom siv. Cov no yog Cov Khoom Pom Zoo SPDs tau soj ntsuam rau siv hauv Hom 1, 2 lossis 3
Kev siv SPD. Xws li cov khoom siv SPDs yuav tsum dhau txhua yam kev nyab xeeb hluav taws xob tsis ua haujlwm
kev ntsuam xyuas raws li teev hom 1, 2 lossis 3 SPDs. Thaum cov SPDs no yog 100% ua raws li kev nyab xeeb
tsis ua hauj lwm kev soj ntsuam taw tes ntawm view, cov hom 1, 2 thiab 3 tivthaiv sib dhos SPDs muaj
tej yam kev mob ntawm kev lees txais xws li raug terminals lossis lwm yam kev tsim kho tshuab
uas xav kom lawv yuav tsum tau nruab los yog tsev nyob rau hauv ib tug sau los ua ke los muab kev tiv thaiv
los ntawm kev kis mus rau qhov chaw nyob lossis lwm yam kev xav tau. Cov Hom 1, 2 lossis 3 Pom tau
Cov khoom siv SPDs yuav tsum tsis txhob tsis meej pem nrog ANSI / UL 1449-2006 Hom 4 Cheebtsam
Kev sib dhos thiab Hom 5 discrete SPD cov khoom uas xav tau cov khoom siv ntxiv
(tejzaum nws muaj kev nyab xeeb disconnectors), tsim thiab kuaj thiaj li yuav siv tau raws li kev ua tiav
ntaus ntawv tiv thaiv.

Hom 4 Component Assembly SPD (Cov Khoom Pom Zoo) –– Cov khoom siv no
Cov rooj sib txoos muaj xws li ib lossis ntau hom 5 SPD cov khoom ua ke nrog lub disconnector
(ib qho lossis sab nraud) lossis ib txoj hauv kev ua raws li cov kev ntsuas tam sim no hauv UL 1449,
Nqe 39.4. Cov no yog cov tsis tiav SPD cov rooj sib txoos, uas feem ntau yog ntsia rau hauv
teev cov khoom siv kawg nkaus yog tias ntev li tag nrho cov kev mob ntawm kev pom zoo tau ntsib. Cov hom 4
kev sibtham sibtham tsis tiav raws li SPD, yuav tsum muaj kev tshuaj xyuas ntxiv thiab tsis muaj
tso cai rau muab ntsia hauv teb raws li SPD sawv ntsug. Feem ntau, cov cuab yeej no yuav tsum tau
ntxiv kev tiv thaiv kev tiv thaiv.

Hom 5 SPD (Cov Khoom Pom Zoo) - Cov khoom siv tsis sib haum xeeb tiv thaiv kev tiv thaiv,
xws li MOVs uas tej zaum yuav mounted rau ib tug luam thaiv board, txuas los ntawm nws cov coj los yog
muab nyob rau hauv ib lub enclosure nrog mounting txhais tau tias thiab wiring terminations. Cov Hom
5 SPD cov khoom tsis tiav raws li SPD, xav tau kev soj ntsuam ntxiv thiab tsis yog
tso cai rau nruab rau hauv daim teb ua ib leeg SPD. Hom 5 SPDs feem ntau yog cov
cov khoom siv hauv kev tsim thiab tsim ua tiav SPDs lossis lwm yam SPD
sibtham.

Tus UL Luv luv Circuit Court tam sim no (SCCR) yog dab tsi?ntiav2017-10-31T16:52:02+08:00

Tus UL Luv luv Circuit Court tam sim no (SCCR) yog dab tsi?

SSCR-Short Circuit Current Rating. Qhov tsim nyog ntawm SPD rau kev siv ntawm AC lub zog hluav taws xob uas muaj peev xwm xa tsis tau ntau tshaj li qhov tshaj tawm rms symmetrical tam sim no ntawm qhov tshaj tawm voltage thaum lub sij hawm luv luv Circuit Court. SCCR tsis zoo ib yam li AIC (Amp Interrupting Capacity). SCCR yog tus nqi ntawm "muaj" tam sim no uas SPD tuaj yeem raug thiab cuam tshuam tsis zoo los ntawm lub zog hluav taws xob nyob rau hauv cov xwm txheej luv luv. Tus nqi tam sim no "kev cuam tshuam" los ntawm SPD feem ntau tsawg dua li "muaj" tam sim no.

UL 1449 thiab National Electric Code (NEC) yuav tsum muaj SCCR (Short Circuit Short Current) uas cim rau tag nrho SPD units. Nws tsis yog qhov kev ntaus nqi, tab sis qhov siab tshaj plaws tam sim no tus SPD tuaj yeem cuam tshuam thaum tsis ua hauj lwm. Lub NEC / UL muaj qhov yuav tsum tau ua kom SPD raug kuaj thiab sau nrog SCCR sib npaug los yog ntau tshaj qhov muaj qhov txhaum tam sim no ntawm qhov kev taw qhia hauv lub cev.

Dab tsi yog qhov tseem ceeb thaum qhia SPD?ntiav2017-10-31T16:31:39+08:00

Dab tsi yog qhov tseem ceeb thaum qhia SPD?

Thaum qhia tus SPD, xa qhov tseeb meej, meej meej meej txog qhov ua kom tau thiab tsim cov qauv. Cov lus qhia yam tsawg yuav tsum muaj:

• Kev ntsuam xyuas UL

• Kev ntsuam xyuas hluav taws

• Qhov ntsuas xyuas luv luv

• Peak surge tam sim no ib hom (LN, LG, thiab NG)

• qhov hluav taws xob thiab kev tsim hluav taws xob

Dab tsi yog Surge Protective Device lossis Surge Arrestor (SPD)?ntiav2017-10-31T16:30:05+08:00

Dab tsi yog Surge Protective Device lossis Surge Arrestor (SPD)?

SPD yog ib qho cuab yeej tsim los txwv kom tsis muaj zog mus rau kev siv hluav taws xob. Nws ua qhov no los ntawm kev faib tawm los yog tsis muaj kev cia siab tam sim no. Ib qho SPD wired li thaum uas tig mus rau cov khoom siv los pab tiv thaiv. Thaum qhov kev poob siab tshaj qhov siab tshaj nws qhov ntsuas tau tsim nws "pib clamp" thiab pib ua lub zog ncaj qha mus rau qhov hluav taws xob grounding system. Ib qho SPD muaj kev tsis txaus siab thaum lub sij hawm no thiab "luv" lub zog rau hauv av. Thaum tus surge tshaj nws "qhib", ces nws tsis ua rau cov ntes tawg ntws tawg.