B57238S479M51 EPCOS Inc, B57238S479M51 Datasheet - Page 3

• Manufacturer Part Number: B57238S479M51
• Description: CURRENT LIMITR INRSH 4.7 OHM 20%
• Manufacturer: EPCOS Inc
• Type: NTCr

Specifications of B57238S479M51

• R @ 25°c: 4.7 Ohm
• Current - Steady State Max: 6.6A
• Tolerance: ±20%
• Diameter: 0.629" (16mm)
• Lead Spacing: 0.295" (7.50mm)
• Resistance: 4.7 Ohms
• Termination Style: Radial
• Operating Temperature Range: - 55 C to + 170 C
• Current Rating: 6.6 Amps
• Power Rating: 3.9 W
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• R @ Current: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: B57238S 479M 51; B57238S0479M051

Reliability data
Test
Storage in
dry heat
Storage in damp
heat, steady state
Rapid temperature
cycling
Endurance
Cyclic
endurance
Transient
load
Note
Please read Cautions and warnings and
Important notes at the end of this document.
Inrush current limiters
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.
Standard
IEC
60068-2-2
IEC
60068-2-78
IEC
60068-2-14
Test conditions
Storage at upper
category temperature
T: 170 C
t: 1000 h
Temperature of air: 40 C
Relative humidity of air: 93%
Duration: 21 days
Lower test temperature:
Upper test temperature: 170 C
Number of cycles: 10
I = I
t: 1000 h
I = I
On-time = 1 min
Cooling time = 6 min
Capacitance = C
Number of cycles: 1000
max
max
, 1000 cycles
Page 3 of 15
test
55 C
(typical)
< 10%
< 5%
< 10%
< 10%
< 10%
< 5%
R
25
/R
25
Remarks
No visible
damage
No visible
damage
No visible
damage
No visible
damage
No visible
damage
No visible
damage
B57238
S238