A circuit is protected by a 20 A type B circuit-breaker to BS EN 60898. The ambient temperature is 20 oC and the circuit is wired in 2.5 mm 2 twin with cpc thermoplastic cable. Calculate the maximum measured Z s. 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.

Circuit-breakers to BS EN 60898-1 may look identical to those complying with BS EN 60947-2 but they are not necessarily inter-changeable. RCD as a term used without any further additional information would revert to the most commonly used general purpose version when quoting tripping times.. Circuit-breakers to BS EN 60947-2 are intended for operation by skilled users and they must be maintained. They are suitable for Pollution Level 3, which includes unheated rooms, boiler rooms, industrial and farming areas.

My topics

Regulation 510.3 of BS 7671 requires that every item of equipment selected and installed must take account of the manufacturer’s instructions.

https://blog.se.com/power-management-metering-monitoring-power-quality/2013/07/16/iec-60947-2-the-all-risk-insurance-for-circuit-breakers/BS EN 60898-1:2019 Electrical accessories. Circuit-breakers for overcurrent protection for household and similar installations Circuit-breakers for a.c. operation

IEC 60947-2 governs circuit breakers (CBs) for industrial applications. They protect electrical power distribution of up to 1000 volts a.c. and 1500 volts d.c. with an entire spectrum of rated currents from 0,5 to 6300A. Utilities and manufacturing facilities often use air circuit breakers (ACBs), molded case circuit breakers (MCCBs), and miniature circuit breakers (MCBs) NAPIT’s Don Holmes looks at the two different circuit-breaker standards, and provides clarification on the differences between them.

Can IEC 60898-1 be used instead of IEC 60947-2?

As mentioned in the blog, MCB manufactured as per IEC 60898 to be used in residential buildings or similar applications. In industrial applications can be used breakers certified as per IEC 60947-2 or IEC 60947-2 and 60898 both. Yes it is safe choice. iC60N 2P @230Vac during the trip has a double break effect (circuit is interrupting in 2 places, per each pole). When testing is carried out at an ambient temperature which is less or greater than 10 oC, the correction factors listed in Table B8 of the OSG or Table A6 of GN 3 should be applied to the maximum Z s values listed. What is the difference between short circuit values mentioned in the 2 standards , Icn values in IEC60898 & Icu value in IEC60947. There is also one observation that Icu values of MCB’s as per IEC60947 are higher than Icn values of MCB as per IEC60898. I am being told by an inspector that we have to use 230Vac when performing permissible earth loop impedance calculations as per BS7671:2018 clause 411.4.4 Zs × Ia ≤ U0 × Cmin.