B57820 EPCOS AG, B57820 Datasheet - Page 7

• Manufacturer Part Number: B57820
• Description: Ntc Thermistors For Temperature Measurement
• Manufacturer: EPCOS AG

Bending strength: Test Ub:
Torsional strength: Test Uc: severity 2
When subjecting leads to mechanical stress, the following should be observed:
Tensile stress on leads
During mounting and operation tensile forces on the leads are to be avoided.
Bending of leads
Bending of the leads directly on the thermistor body is not permissible.
A lead may be bent at a minimum distance of twice the wire's diameter +2 mm from the solder
joint on the thermistor body. During bending the wire must be mechanically relieved at its outlet.
The bending radius should be at least 0.75 mm.
Twisting of leads
The twisting (torsion) by 180 of a lead bent by 90 is permissible at 6 mm from the bottom of the
thermistor body.
4
When thermistors are sealed, potted or overmolded, there must be no mechanical stress caused
by thermal expansion during the production process (curing / overmolding process) and during
later operation. The upper category temperature of the thermistor must not be exceeded. Ensure
that the materials used (sealing / potting compound and plastic material) are chemically neutral.
5
If cleaning is necessary, mild cleaning agents such as ethyl alcohol and cleaning gasoline are
recommended. Cleaning agents based on water are not allowed. Ultrasonic cleaning methods are
permissible.
6
In order to maintain their solderability, thermistors must be stored in a non-corrosive atmosphere.
Humidity, temperature and container materials are critical factors.
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, use the SMDs as soon as possible.
Please read Cautions and warnings and
Important notes at the end of this document.
Temperature measurement and compensation
Leadless NTCs
Sealing and potting
Cleaning
Storage
Two 90 -bends in opposite directions at a weight of 0.25 kg.
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).
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B57820M
M820