B57238S250M EPCOS Inc, B57238S250M Datasheet - Page 8

• Manufacturer Part Number: B57238S250M
• Description: Thermistors - NTC 25 Ohms 3.4amps 3265k
• Manufacturer: EPCOS Inc
• Type: NTCr
• Series: B57238r

Specifications of B57238S250M

• Resistance: 25 Ohms
• Tolerance: 20 %
• Termination Style: Radial
• Operating Temperature Range: - 55 C to + 170 C
• Current Rating: 3.4 Amps
• Dimensions: 16 mm Dia. x 7 mm W x 23 mm H
• Lead Spacing: 7.5 mm
• Power Rating: 3.9 W
• Thermistor Type: NTC
• Thermistor Tolerance: ± 20%
• Beta Value (k): 3265K
• Thermistor Case Style: Radial Leaded
• No. Of Pins: 2
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Mounting instructions
1
1.1
Leaded thermistors comply with the solderability requirements specified by CECC.
When soldering, care must be taken that the NTC thermistors are not damaged by excessive
heat. The following maximum temperatures, maximum time spans and minimum distances have
to be observed:
Bath temperature
Soldering time
Distance from thermistor
Under more severe soldering conditions the resistance may change.
Solderability (test to IEC 60068-2-58)
Preconditioning: Immersion into flux F-SW 32.
Evaluation criterion: Wetting of soldering areas 95%.
Solder
SnAg (3.0 ... 4.0), Cu (0.5 ... 0.9)
1.1.1
Preconditioning: Immersion into flux F-SW 32.
Evaluation criterion: Leaching of side edges 1/3.
Solder
SnAg (3.0 ... 4.0), Cu (0.5 ... 0.9)
Please read Cautions and warnings and
Important notes at the end of this document.
Inrush current limiters
ICLs
Soldering
Leaded NTC thermistors
Resistance to soldering heat (test to IEC 60068-2-58)
Dip soldering
max. 260 C
max. 4 s
min. 6 mm
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Bath temperature ( C)
245 3
Bath temperature ( C)
260
Iron soldering
max. 360 C
max. 2 s
min. 6 mm
5
Dwell time (s)
3
Dwell time (s)
10
B57238
S238