© A
BB
ST
OT
Z K
ON
TA
KT
- 1
07
-05-
2002
MCB Tripping – Characteristics
MCB´s Knowhow
ABB STOTZ KONTAKT
© A
BB
ST
OT
Z K
ON
TA
KT
DE
ST
O/X
2 R
H -
2
MCB tripping characteristics
40 I1
40 I2
I3
I4
- 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 I3
- Electromagnetic tripping current rsp. test current: trip at least at I4
General Time / current relationGeneral Time / current relation
1. Thermal tripping
2. Electromagnetic tripping
Basics:Basics:40 40
0,04
120
20
10
64
2
1
20
40
10
4
2
1
0,60,4
0,2
0,1
0,06
0,02
0,011 1,5 2 3 4 5 6 8 10 15 20 30
6
60
I3 I4
I1 I2
Tr i
pp
ing
tim
es
ec
on
ds
min
ute
s
© A
BB
ST
OT
Z K
ON
TA
KT
DE
ST
O/X
2 R
H -
3
MCB tripping characteristics
DC-current increases the magnetic tripping valuesby factor 1,5
40
0,04
120
20
10
64
2
1
20
40
10
4
2
1
0,60,4
0,2
0,1
0,06
0,02
0,011 1,5 2 3 4 5 6 8 10 15 20 30
6
60
AC
DC
Tri
pp
ing
tim
es
ec
on
ds
min
ute
s
Multiple of rated current
Basics:Basics:
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
© A
BB
ST
OT
Z K
ON
TA
KT
DE
ST
O/X
2 R
H -
4
MCB tripping characteristics
"B"-characteristic"B"-characteristic
acc. EN 60898 rsp. IEC 898: standard for acc. EN 60898 rsp. IEC 898: standard for miniature circuit breakers to be used in miniature circuit breakers to be used in residential or similar applicationsresidential or similar applications
40 I1
40 I2
I3
I4
Thermal non tripping: 1,13 x In
Thermal tripping: 1,45 x In
Magnetic non tripping: 3 x In
Magnetic tripping: 5 x In
Applications:•low duty applications without starting or inrush currents
40
0,04
120
20
10
64
2
1
20
40
10
4
2
1
0,60,4
0,2
0,1
0,06
0,02
0,011 1,5 2 3 4 5 6 8 10 15 20 30
6
60
B
40 I1 40 I2
I3 I4
min
ute
ss
ec
on
ds
Tri
pp
ing
tim
e
Multiple of rated current
© A
BB
ST
OT
Z K
ON
TA
KT
DE
ST
O/X
2 R
H -
5
MCB tripping characteristics
““C"-characteristicC"-characteristic
acc. EN 60898 rsp. IEC 898: standard for acc. EN 60898 rsp. IEC 898: standard for miniature circuit breakers to be used in miniature circuit breakers to be used in residential or similar applicationsresidential or similar applications
40 I1
40 I2
I3
I4
Thermal non tripping: 1,13 x In
Thermal tripping: 1,45 x In
Magnetic non tripping: 5 x In
Magnetic tripping: 10 x In
Applications:•low duty applications with medium starting or inrush currents and low loop impendance
40
0,04
120
20
10
64
2
1
20
40
10
4
2
1
0,60,4
0,2
0,1
0,06
0,02
0,011 1,5 2 3 4 5 6 8 10 15 20 30
6
60
C
min
ute
ss
ec
on
ds
Tri
pp
ing
tim
e
Multiple of rated current
© A
BB
ST
OT
Z K
ON
TA
KT
DE
ST
O/X
2 R
H -
6
MCB tripping characteristics
““D"-characteristicD"-characteristic
acc. EN 60898 rsp. IEC 898: standard for acc. EN 60898 rsp. IEC 898: standard for miniature circuit breakers to be used in miniature circuit breakers to be used in residential or similar applicationsresidential or similar applications
40 I1
40 I2
I3
I4
Thermal non tripping: 1,13 x In
Thermal tripping: 1,45 x In
Magnetic non tripping: 10 x In
Magnetic tripping: 20 x In
Applications:•high duty applications with very high starting or inrush currents but low loop impendance
40
0,04
120
20
10
64
2
1
20
40
10
4
2
1
0,60,4
0,2
0,1
0,06
0,02
0,011 1,5 2 3 4 5 6 8 10 15 20 30
6
60
D
min
ute
ss
ec
on
ds
Tri
pp
ing
tim
e
Multiple of rated current
© A
BB
ST
OT
Z K
ON
TA
KT
DE
ST
O/X
2 R
H -
7
MCB tripping characteristics
"B,C;D"-characteristics"B,C;D"-characteristics
acc. EN 60898 rsp. IEC 898: Standard for acc. EN 60898 rsp. IEC 898: Standard for miniature circuit breakers to be used in miniature circuit breakers to be used in residential or similar applications.residential or similar applications.
• For low duty installations• Rough leveled features for average applications• Restricted thermal protection, allowing : 1,45 x In • 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“.
I3
I4
40
0,04
120
20
10
64
2
1
20
40
10
4
2
1
0,60,4
0,2
0,1
0,06
0,02
0,011 1,5 2 3 4 5 6 8 10 15 20 30
6
60
DCB
min
ute
ss
ec
on
ds
Tri
pp
ing
tim
e
Multiple of rated current
© A
BB
ST
OT
Z K
ON
TA
KT
DE
ST
O/X
2 R
H -
8
MCB tripping characteristics
““STOTZ“STOTZ“„„Z“„K“characteristicsZ“„K“characteristics
acc. EN 60947-2 rsp. IEC 947-2:acc. EN 60947-2 rsp. IEC 947-2:standard for industrial switchgearstandard for industrial switchgear
„The tailormade solution for commercial and industrial applications“
40
0,04
120
20
10
64
2
1
20
40
10
4
2
1
0,60,4
0,2
0,1
0,06
0,02
0,011 1,5 2 3 4 5 6 8 10 15 20 30
6
60
DCBZ K
min
ute
ss
ec
on
ds
Tri
pp
ing
tim
e
Multiple of rated current
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
© A
BB
ST
OT
Z K
ON
TA
KT
DE
ST
O/X
2 R
H -
9
MCB tripping characteristics
““Z"-characteristicZ"-characteristic
acc. EN 60947-2 rsp. IEC 947-2:acc. EN 60947-2 rsp. IEC 947-2:standard for industrial switchgearstandard for industrial switchgear
40 I1
40 I2
I3
I4
Thermal non tripping: 1,05 x In
Thermal tripping: 1,2 x In
Magnetic non tripping: 2 x In
Magnetic tripping: 3 x In
A sensitive characteristic to protect highly sensitive equipment such as:
•0,14mm2 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
64
2
1
20
40
10
4
2
1
0,60,4
0,2
0,1
0,06
0,02
0,011 1,5 2 3 4 5 6 8 10 15 20 30
6
60
DCBZ
min
ute
ss
ec
on
ds
Tri
pp
ing
tim
e
Multiple of rated current
© A
BB
ST
OT
Z K
ON
TA
KT
DE
ST
O/X
2 R
H -
10
MCB tripping characteristics
40
0,04
120
20
10
64
2
1
20
40
10
4
2
1
0,60,4
0,2
0,1
0,06
0,02
0,011 1,5 2 3 4 5 6 8 10 15 20 30
6
60
DCBK
““K"-characteristicK"-characteristicacc. EN 60947-2 rsp. IEC 947-2:acc. EN 60947-2 rsp. IEC 947-2:standard for industrial switchgearstandard for industrial switchgear
40 I1
40 I2
I3
I4
Thermal non tripping: 1,05 x In
Thermal tripping: 1,2 x In
Magnetic non tripping S270: 8 x In
Magnetic tripping S270:12 x In
Magnetic non tripping S280: 10 x In
Magnetic tripping S280:14 x In
I3
I4
The right choice for high duty applicationwith 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
min
ute
ss
ec
on
ds
Tri
pp
ing
tim
e
Multiple of rated current
© A
BB
ST
OT
Z K
ON
TA
KT
DE
ST
O/X
2 R
H -
11
MCB tripping characteristics