1. © ABB STOTZ KONTAKT - 1 07-05-2002 ABB MCB Tripping – Characteristics MCB´s Knowhow ABB STOTZ KONTAKT

2. © ABB STOTZ KONTAKT DESTO/X2 RH - 2 ABB MCB tripping characteristics I 1 - Thermal non-tripping current rsp. Low test current - Thermal tripping current rsp. High test current - Electromagnetic non-tripping current rsp. test current: hold surges of I 3 - Electromagnetic tripping current rsp. test current: trip at least at I 4 General Time / current relation 1. Thermal tripping 2. Electromagnetic trippingBasics: 40 0,04 120 20 10 6 4 2 1 20 40 10 4 2 1 0,6 0,4 0,2 0,1 0,06 0,02 0,01 1 1,5 2 3 4 5 6 8 10 15 20 30 6 60 I 3 I 4 I 1 I 2 Tripping time seconds minutes

3. © ABB STOTZ KONTAKT DESTO/X2 RH - 3 ABB MCB tripping characteristics DC-current increases the magnetic tripping values by factor 1,5Basics: Magnetic tripping: AC, 100 Hz= factor 1.1 AC, 200 Hz= factor 1.2 AC, 400 Hz= factor 1.5 DC= factor 1.5 Thermal tripping is not dependent on frequency

4. © ABB STOTZ KONTAKT DESTO/X2 RH - 4 ABB MCB tripping characteristics "B"-characteristic acc. EN 60898 rsp. IEC 898: standard for miniature circuit breakers to be used in residential or similar applications Thermal non tripping: 1,13 x I n Thermal tripping:1,45 x I n Magnetic non tripping:3 x I n Magnetic tripping:5 x I n Applications: low duty applications without starting or inrush currents 40 0,04 120 20 10 6 4 2 1 20 40 10 4 2 1 0,6 0,4 0,2 0,1 0,06 0,02 0,01 1 1,5 2 3 4 5 6 8 10 15 20 30 6 60 B minutes seconds Tripping time Multiple of rated current

5. © ABB STOTZ KONTAKT DESTO/X2 RH - 5 ABB MCB tripping characteristics “C"-characteristic acc. EN 60898 rsp. IEC 898: standard for miniature circuit breakers to be used in residential or similar applications Thermal non tripping: 1,13 x I n Thermal tripping:1,45 x I n Magnetic non tripping:5 x I n Magnetic tripping:10 x I n Applications: low duty applications with medium starting or inrush currents and low loop impendance 40 0,04 120 20 10 6 4 2 1 20 40 10 4 2 1 0,6 0,4 0,2 0,1 0,06 0,02 0,01 1 1,5 2 3 4 5 6 8 10 15 20 30 6 60 C minutes seconds Tripping time Multiple of rated current

6. © ABB STOTZ KONTAKT DESTO/X2 RH - 6 ABB MCB tripping characteristics “D"-characteristic acc. EN 60898 rsp. IEC 898: standard for miniature circuit breakers to be used in residential or similar applications Thermal non tripping: 1,13 x I n Thermal tripping:1,45 x I n Magnetic non tripping:10 x I n Magnetic tripping:20 x I n Applications: high duty applications with very high starting or inrush currents but low loop impendance 40 0,04 120 20 10 6 4 2 1 20 40 10 4 2 1 0,6 0,4 0,2 0,1 0,06 0,02 0,01 1 1,5 2 3 4 5 6 8 10 15 20 30 6 60 D minutes seconds Tripping time Multiple of rated current

7. © ABB STOTZ KONTAKT DESTO/X2 RH - 7 ABB MCB tripping characteristics "B,C;D"-characteristics acc. EN 60898 rsp. IEC 898: Standard for miniature circuit breakers to be used in residential or similar applications. For low duty installations Rough leveled features for average applications Restricted thermal protection, allowing : 1,45 x I n Extreme high of „D“ characteristic may lead to delayed tripping time, damaging conductors and equipment Using „D“, low loop impedances, meaning larger cross sections of conductors is a „must“. 40 0,04 120 20 10 6 4 2 1 20 40 10 4 2 1 0,6 0,4 0,2 0,1 0,06 0,02 0,01 1 1,5 2 3 4 5 6 8 10 15 20 30 6 60 DC B minutes seconds Tripping time Multiple of rated current

8. © ABB STOTZ KONTAKT DESTO/X2 RH - 8 ABB MCB tripping characteristics “STOTZ“„Z“„K“characteristics acc. EN 60947-2 rsp. IEC 947-2: standard for industrial switchgear „The tailormade solution for commercial and industrial applications“ Compared to tripping characteristics „B“,“C“, „D“ the STOTZ characteristics „K“ and „Z“ offer a higher degree of protection. This means a higher degree of safety in both, planning and operation

9. © ABB STOTZ KONTAKT DESTO/X2 RH - 9 ABB MCB tripping characteristics “Z"-characteristic acc. EN 60947-2 rsp. IEC 947-2: standard for industrial switchgear Thermal non tripping: 1,05 x I n Thermal tripping:1,2 x I n Magnetic non tripping:2 x I n Magnetic tripping:3 x I n A sensitive characteristic to protect highly sensitive equipment such as: 0,14mm 2 cable sets applications with limit switches reed contacts in burglar alarm systems sensor technology actuators in bus systems printed boards with its semiconductors 40 0,04 120 20 10 6 4 2 1 20 40 10 4 2 1 0,6 0,4 0,2 0,1 0,06 0,02 0,01 1 1,5 2 3 4 5 6 8 10 15 20 30 6 60 DC B Z minutes seconds Tripping time Multiple of rated current

10. © ABB STOTZ KONTAKT DESTO/X2 RH - 10 ABB MCB tripping characteristics 40 0,04 120 20 10 6 4 2 1 20 40 10 4 2 1 0,6 0,4 0,2 0,1 0,06 0,02 0,01 1 1,5 2 3 4 5 6 8 10 15 20 30 6 60 DC B K “K"-characteristic acc. EN 60947-2 rsp. IEC 947-2: standard for industrial switchgear Thermal non tripping: 1,05 x I n Thermal tripping:1,2 x I n Magnetic non tripping S270:8 x I n Magnetic tripping S270:12 x I n Magnetic non tripping S280:10 x I n Magnetic tripping S280:14 x I n The right choice for high duty application with high starting or inrush currents: Motors, fan sets Power supply units: i.e 24V DC supply for intelligent building automation systems Charging sets; i.e for electrical forklift trucks Extra low voltage lamps, high performance tools, electronic ballasts Welding- and control power transformer minutes seconds Tripping time Multiple of rated current

11. © ABB STOTZ KONTAKT DESTO/X2 RH - 11 ABB MCB tripping characteristics