Square D KQ B 32 AMP MCB 240 v BS60898 10B132 A 10Ka CIRCUIT BREAKER

Product Information

Are AC MCB’s able to be used for DC applications? If so, What is it about the Ac rated MCB’s that makes this possible? My thinking is that by nature AC signals reverse polarity each cycle and therefore it would not matter which way the MCB was wired. In any case you should pay attention on technical characteristics of devices like: Icu, Ics, Ue, Uimp, pollution degree, ect. Oftentimes users confuse the standards – particularly “prescribers” e.g., those people who draw up specifications in invitations to tender. Utility procurement managers can also get things wrong. As to how they mix up the standards, I can’t say for certain. But happen it does.

Circuit-breakers to BS EN 60898-1 are safe and easy to use, even after many years without maintenance. They are suitable for Pollution Level 2 and their classifications and applications are shown in Tables 1a, and 1b.

My topics

Cmin is something of a nonsense distraction which was recently introduced. In reality it has little bearing upon Zs outcomes and I have never understood why it was included as a correction factor other than to serve to get us to install larger cables. I cs is expressed as a percentage ratio of I cu and gives the maximum short-circuit current a cb can break three times and still function in normal service. Or take the tripping characteristics: IEC 60898-1 clearly describes B, C, and D curves with ratio to rated current, while in IEC 60947-2 the instantaneous tripping release may be adjustable according to the need of the user, or pre-defined by the manufacturer, with ±20% tolerance. This is the reason why manufacturers additionally provide a wide scope of different curves: K, Z, MA.

According to these standards any manufacturers could provide life time warranty. Aging of Plastic covers, degradation of Bi-metals / Springs & No calibration for a long time as if it a life time product. Manufacturers warn against installing circuit- breakers of one manufacturer as replacements for cbs of another manufacturer, without the necessary verification of performance. Many ABB fuses require more tripping current (Ia) to operate in 0.2 seconds compared to a 0.4 second trip.Dear Mostafa, in IEC 898-1 it is mainly used definition of Icn (rated (nominal) breaking capacity) but not Icu (ultimate breaking capacity) and it makes the difference.

Shall any where mention on BS or IEC that we need to do Field Trip Test for each MCB’s type B,C,D .We are using SCHNEIDER MCB,s and the project is for housing. A cb designed for Pollution Level 2 conditions would not be suitable for harsh outdoor or humid applications that require Pollution Level 3. We have MCCB NSX 250H with Micrologic 2.2 trip unit installed in our utility station. We would like to connect 440V HPU with star-delta starter, inrush/peak start up current is abt. 448A, FLA is abt. 198A (HPU motor has it’s own overload protection). Is this breaker fit for purpose along with Micrologic 2.2 trip unit? What will be be approximate short-time delay timing for 448A inrush?

Many more differences between IEC 60898-1 and IEC 60947-2?

BS EN 60898-1:2019 Electrical accessories. Circuit-breakers for overcurrent protection for household and similar installations Circuit-breakers for a.c. operation In the product catalog you can find that range 5SY4 is only certified per EN60898-1 and EN60947-2. Unfortunately I found no value for Icu there. It has Icn=10kA only. I do not have example of the breaker to comment this point. Icu is given only for range 5SY8. There will be circumstances where a designer has specified requirements which are particular to an electrical installation. Hello Vlad, our customer need 10kAIC circuit breaker for Lighting / C.O. loads. Is it safe to offer the iC60n where it is 20kAIC at 230Vac,2P @ 947-2 standard and 6kAIC @ 898-1 standard?

No. Consequences can be serious if residential CBs are used instead of industrial ones. An MCB designed for indoor, pollution degree 2 conditions would be inadequate for harsh, outdoor applications that require pollution degree 3. Assemblies such as distribution boards are validated with specific circuit-breakers installed and these cbs are usually from the same manufacturer as the distribution board. Where cbs made by a different manufacturer are to be installed, verification will have to be undertaken by the manufacturer of the distribution board to BS EN 61439-2 or BS EN 61439-3. Fitting unverified devices will invalidate any verification and the warranty. How comes BS 88 and bs1361 fuses have two tables for 0.4s and 5S but 60898 fuses have one which covers both. The most suitable solution is for MCBs that are certified by both IEC standards since their performance meets requirements for use in residential installations and is high enough for use in industry and infrastructure applications. Due to the high level of protection performance of these CBs, they should be used at least for the incoming electrical switchboards in buildings applications. Appliance for MCB’s to standards in different applications of useI work for the utility in South Africa and am researching the use of MCB’s at the PUC between the utility and an IPP. Two requirements that ensure reliability of circuit- breakers are the ultimate breaking capacity (I cu) and service breaking capacity (I cs).