Inrush current limiters
ICLs
B57238
S238
1)
1)
R25 Imax
No. of
B25/100
Ctest
Ctest
Param. Param. Ordering code
(0...65 °C) R/T char-
230 V 110 V for R(I)1) for R(I)1)
Ω
A
4.0
3.4
acteristic
1210
1210
K
3265
3265
µF
700
700
µF
k
n
2800 1.84
2800 1.88
ꢀ1.42
ꢀ1.40
B57238S0220M000
B57238S0250M000
22
25
Reliability data
Test
Standard
IEC
Test conditions
∆R25/R25
(typical)
Remarks
Storage in
dry heat
Storage at upper
< 10%
No visible
damage
60068-2-2 category temperature
T: 170 °C
t: 1000 h
Storage in damp
heat, steady state
IEC
Temperature of air: 40 °C
< 5%
No visible
damage
60068-2-78 Relative humidity of air: 93%
Duration: 21 days
Rapid temperature IEC
Lower test temperature: ꢀ55 °C < 10%
No visible
damage
cycling
60068-2-14 Upper test temperature: 170 °C
Number of cycles: 10
Endurance
I = Imax
t: 1000 h
< 10%
< 10%
No visible
damage
Cyclic
endurance
I = Imax, 1000 cycles
On-time = 1 min
No visible
damage
Cooling time = 6 min
Transient
load
Capacitance = Ctest
Number of cycles: 1000
< 5%
No visible
damage
Cautions and warnings for ICLs
The self-heating of a thermistor during operation depends on the load applied and the applicable
dissipation factor.
When loaded with maximum allowable current/power and the specified dissipation factor is taken
as a basis, the NTC thermistor may reach a mean temperature of up to 250 °C.
The heat developed during operation will also be dissipated through the lead wires. So the
contact areas, too, may become quite hot at maximum load.
When mounting NTC thermistors you have to ensure that there is an adequate distance between
the thermistor and all parts which are sensitive to heat or combustible.
1) For details on the capacitance Ctest as well as on the parameters k and n refer to "Application Notes", chapters 2.6 and 2.7.
Please read Important notes and
Page 3 of 6
Cautions and warnings at the end of this document.
EPCOS [ EPCOS ]
