Inrush current limiters
ICLs
B57238
S238
R
25
Ω
22
25
I
max
(0...65
°C)
A
4.0
3.4
No. of
R/T char-
acteristic
1210
1210
B
25/100
K
3265
3265
C
test1)
230 V
µF
700
700
C
test1)
110 V
µF
2800
2800
Param. Param. Ordering code
for R(I)
1)
for R(I)
1)
k
n
1.84
1.42
B57238S0220M000
1.88
1.40
B57238S0250M000
Reliability data
Test
Storage in
dry heat
Standard
IEC
60068-2-2
Test conditions
∆R
25
/R
25
(typical)
< 10%
Remarks
No visible
damage
Storage in damp
heat, steady state
Rapid temperature
cycling
Endurance
Cyclic
endurance
Transient
load
Storage at upper
category temperature
T: 170
°C
t: 1000 h
IEC
Temperature of air: 40
°C
60068-2-78 Relative humidity of air: 93%
Duration: 21 days
IEC
Lower test temperature: 55
°C
60068-2-14 Upper test temperature: 170
°C
Number of cycles: 10
I = I
max
t: 1000 h
I = I
max
, 1000 cycles
On-time = 1 min
Cooling time = 6 min
Capacitance = C
test
Number of cycles: 1000
< 5%
No visible
damage
No visible
damage
No visible
damage
No visible
damage
No visible
damage
< 10%
< 10%
< 10%
< 5%
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 C
test
as well as on the parameters k and n refer to "Application Notes", chapters 2.6 and 2.7.
Please read
Important notes
and
Cautions and warnings
at the end of this document.
Page 3 of 6
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