Temperature measurement
Probe assemblies
B57500M
M500
Applications
Air sensor for air conditioning
(not for use in evaporators)
Features
Thermistor with epoxy resin encapsulation
PVC-insulated wires (black) with tinned
ends, AWG 26, T
max
= 105
°C
Options
Alternative resistance ratings, rated
temperatures, resistance tolerances and
wire lengths, AWG 22 or AWG 24 available
on request.
Delivery mode
Bulk
Dimensional drawing
Dimensions in mm
General technical data
Climatic category
Max. power
Resistance tolerance
Rated temperature
Dissipation factor
Thermal cooling time constant
Heat capacity
Insulation resistance
Test voltage
(IEC 60068-1)
(at 25
°C)
30/100/56
60
±3
25
approx. 3
approx. 20
approx. 60
> 100
1.25
(in air)
(in air)
(V = 100 V DC)
(t = 1 s)
P
25
∆R
R
/R
R
T
R
δ
th
τ
c
C
th
R
ins
V
test
mW
%
°C
mW/K
s
mJ/K
MΩ
kV AC
Electrical specification and ordering codes
R
25
Ω
10 k
Note
Only for use in dry environmental conditions.
No. of R/T
characteristic
8016
B
25/100
K
3988
±0.5%
Ordering code
B57500M0103A005
Please read
Cautions and warnings
and
Important notes
at the end of this document.
Page 2 of 9
Temperature measurement
Probe assemblies
B57500M
M500
Reliability data
Test
Storage in
dry heat
Standard
IEC
60068-2-2
Test conditions
∆R
25
/R
25
(typical)
< 2%
Remarks
No visible
damage
Storage at upper
category temperature
T: 100
°C
t: 1000 h
Storage in damp
IEC
Temperature of air: 40
°C
heat, steady state
60068-2-78 Relative humidity of air: 93%
Duration: 56 days
Storage in coldness
Storage at lower
category temperature
T: 30
°C
t: 1000 h
Rapid temperature IEC
Lower test temperature: 30
°C
cycling (in air)
60068-2-14 Upper test temperature: 100
°C
Time to change from lower to
upper temperature: <30 s
Number of cycles: 1000
Medium: air
Vibration
IEC
Frequency range: 5 to 500 Hz
resistance
60068-2-6
Amplitude: 7.5 mm, 2
g
Duration: 3 x 8 h
Long-term stability
Temperature: 100
°C
(empirical value)
t: 10000 h
Voltage proof test
1250 V AC,
1s
Insulation test
The sensors are placed in a
vessel containing metallic balls of
1 mm diameter (with total
immersed head). The applied
voltage is 100 V DC.
Note
< 2%
No visible
damage
No visible
damage
< 2%
< 2%
No visible
damage
< 3%
No visible
damage
No visible
damage
No flashover
Above
100 MΩ
< 3%
Contact of NTC thermistors with any liquids and solvents shall be prevented. It must be
ensured that no water enters the NTC thermistors (e.g. through plug terminals).
Avoid dewing and condensation unless thermistor is specified for these conditions.
Please read
Cautions and warnings
and
Important notes
at the end of this document.
Page 3 of 9
Temperature measurement
Probe assemblies
B57500M
M500
Cautions and warnings
See "Important notes".
Storage
Store thermistors only in original packaging. Do not open the package prior to storage.
Storage conditions in original packaging: storage temperature 25
°C
... +45
°C,
relative
humidity
≤75%
annual mean, <95% maximum 30 days per annum, dew precipitation is
inadmissible.
Do not store thermistors where they are exposed to heat or direct sunlight. Otherwise, the
packing material may be deformed or components may stick together, causing problems during
mounting.
Avoid contamination of thermistor surface during storage, handling and processing.
Avoid storage of thermistors in harmful environments like corrosive gases (SO
x
, Cl etc).
Use the components as soon as possible after opening the factory seals, i.e. the
polyvinyl-sealed packages.
Solder thermistors within the time specified after shipment from EPCOS.
For leaded components this is 24 months, for SMD components with nickel barrier termination
12 months, for SMD components with AgPd termination 6 months.
Handling
NTC thermistors must not be dropped. Chip-offs or any other damage must not be caused
during handling of NTCs.
Do not touch components with bare hands. Gloves are recommended.
Avoid contamination of thermistor surface during handling.
Washing processes may damage the product due to the possible static or cyclic mechanical
loads (e.g. ultrasonic cleaning). They may cause cracks to develop on the product and its parts,
which might lead to reduced reliability or lifetime.
Bending / twisting leads
A lead (wire) may be bent at a minimum distance of twice the wire’s diameter plus 4 mm from
the component head or housing. When bending ensure the wire is mechanically relieved at the
component head or housing. The bending radius should be at least 0.75 mm.
Twisting (torsion) by 180° of a lead bent by 90° is permissible at 6 mm from the bottom of the
thermistor body.
Soldering
Use resin-type flux or non-activated flux.
Insufficient preheating may cause ceramic cracks.
Rapid cooling by dipping in solvent is not recommended.
Complete removal of flux is recommended.
Please read
Cautions and warnings
and
Important notes
at the end of this document.
Page 5 of 9