Mounting
Electrode must not be scratched before/during/after the mounting process.
Contacts and housing used for assembly with thermistor have to be clean before mounting. Es-
pecially grease or oil must be removed.
When PTC thermistors are encapsulated with sealing material, the precautions given in chapter
"Mounting instructions", "Sealing and potting" must be observed.
When the thermistor is mounted, there must not be any foreign body between the electrode of
the thermistor and the clamping contact.
The minimum force of the clamping contacts pressing against the PTC must be 10 N.
During operation, the thermistor’s surface temperature can be very high. Ensure that adjacent
components are placed at a sufficient distance from the thermistor to allow for proper cooling at
the thermistors.
Ensure that adjacent materials are designed for operation at temperatures comparable to the
surface temperature of thermistor. Be sure that surrounding parts and materials can withstand
this temperature.
Avoid contamination of thermistor surface during processing.
Operation
Use thermistors only within the specified temperature operating range.
Use thermistors only within the specified voltage and current ranges.
Environmental conditions must not harm the thermistors. Use thermistors only in normal at-
mospheric conditions. Avoid use in deoxidizing gases (chlorine gas, hydrogen sulfide gas, am-
monia gas, sulfuric acid gas etc), corrosive agents, humid or salty conditions. Contact with any
liquids and solvents should be prevented.
Be sure to provide an appropriate fail-safe function to prevent secondary product damage
caused by abnormal function (e.g. use VDR for limitation of overvoltage condition).
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Important notes at the end of this document.
Symbols and terms
A Area
C
th
Heat capacity
f Frequency
I Current
I
max
Maximum current
I
R
Rated current
I
PTC
PTC current
I
r
Residual currrent
I
r,oil
Residual currrent in oil (for level sensors)
I
r,air
Residual currrent in air (for level sensors)
I
RMS
Root-mean-square value of current
I
S
Switching current
I
Smax
Maximum switching current
LCT Lower category temperature
N Number (integer)
N
c
Operating cycles at V
max
, charging of capacitor
N
f
Switching cycles at V
max
, failure mode
P Power
P
25
Maximum power at 25 °C
P
el
Electrical power
P
diss
Dissipation power
R
G
Generator internal resistance
R
min
Minimum resistance
R
R
Rated resistance
R
R
Tolerance of R
R
R
P
Parallel resistance
R
PTC
PTC resistance
R
ref
Reference resistance
R
S
Series resistance
R
25
Resistance at 25 °C
R
25,match
Resistance matching per reel/ packing unit at 25 °C
R
25
Tolerance of R
25
T Temperature
t Time
T
A
Ambient temperature
t
a
Thermal threshold time
T
C
Ferroelectric Curie temperature
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Important notes at the end of this document.
t
E
Settling time (for level sensors)
T
R
Rated temperature
T
sense
Sensing temperature
T
op
Operating temperature
T
PTC
PTC temperature
t
R
Response time
T
ref
Reference temperature
T
Rmin
Temperature at minimum resistance
t
S
Switching time
T
surf
Surface temperature
UCT Upper category temperature
V or V
el
Voltage (with subscript only for distinction from volume)
V
RMS
Root-mean-square value of voltage
V
BD
Breakdown voltage
V
ins
Insulation test voltage
V
link,max
Maximum link voltage
V
max
Maximum operating voltage
V
max,dyn
Maximum dynamic (short-time) operating voltage
V
meas
Measuring voltage
V
meas,max
Maximum measuring voltage
V
R
Rated voltage
V
PTC
Voltage drop across a PTC thermistor
α Temperature coefficient
Tolerance, change
δ
th
Dissipation factor
τ
th
Thermal cooling time constant
λ Failure rate
Lead spacing (in mm)
Abbreviations / Notes
Surface-mount devices
* To be replaced by a number in ordering codes, type designations etc.
+ To be replaced by a letter
All dimensions are given in mm.
The commas used in numerical values denote decimal points.
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Important notes at the end of this document.

B59184B1120A151

Mfr. #:
Manufacturer:
EPCOS / TDK
Description:
THERMISTOR PTC 50 OHM 15% DISC
Lifecycle:
New from this manufacturer.
Delivery:
DHL FedEx Ups TNT EMS
Payment:
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