B59421A0075A062_1011 Datasheet, PDF (26/32 Pages) EPCOS – PTC thermistors as limit temperature sensors

Sensors
Limit temperature sensors, EIA sizes 0402, 0603 and 0805
Superior series
Do not store SMDs where they are exposed to heat or direct sunlight. Otherwise, the packing ma-
terial may be deformed or SMDs may stick together, causing problems during mounting.
After opening the factory seals, such as polyvinyl-sealed packages, it is recommended to use the
components as soon as possible.
3
Conductive adhesion
An alternative to soldering is the gluing of thermistors with conductive adhesives. The benfit of
this method is that it involves no thermal stress. The adhesives used must be chemically inert and
suitable for the temperatures arising at the surface of the termistor.
4
Clamp contacting
Pressure contacting by springs is required for applications involving frequent switching and high
turn-on powers. Soldering is not allowed for such applications in order to avoid operational failure
in the long term. PTC thermistors for heating and motor starting have metallized surfaces for
clamp contacting.
5
Robustness of terminations
The leads meet the requirements of IEC 60068-2-21. They may not be bent closer than 4 mm
from the solder joint on the thermistor body or from the point at which they leave the
feedthroughs. During bending, any mechanical stress at the outlet of the leads must be removed.
The bending radius should be at least 0.75 mm.
Tensile strength:
Test Ua1:
Leads
∅ ≤ 0.5 mm = 5 N
∅ > 0.5 mm = 10 N
Bending strength: Test Ub:
Two 90°-bends in opposite directions at a weight of 0.25 kg.
Torsional strength: Test Uc: severity 2
The lead is bent by 90° at a distance of 6 to 6.5 mm from the thermistor body.
The bending radius of the leads should be approx. 0.75 mm. Two torsions of
180° each (severity 2).
Please read Cautions and warnings and
Important notes at the end of this document.
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