PTC thermistors for motor starting
Metallized disks for
low power consumption
Series/Type:
B59553, B59557
Date:
March 2006
EPCOS AG 2006. Reproduction, publication and dissemination of this publication, enclosures hereto and the
information contained therein without EPCOS' prior express consent is prohibited.
Applications
Time delay in turning off the auxiliary winding of single-phase AC motors
Features
Metallization: CrNi (sputtered) + Ag (screen-printed)
Excellent long-term reliability
Suitable for clamp contacting
UL approval to UL 1434 (file number E69802)
RoHS-compatible
Delivery mode
Bulk
Dimensional drawing
General technical data
Switching cycles
N
>100000
Operating temperature range
(V = 0)
T
op
+5/+80
C
Operating temperature range
(V = V
max
)
T
op
+5/+80
C
Motor Starting
Low power consumption
A536 ... A556
Page 2 of 7
Please read Important notes and
Cautions and warnings at the end of this document.
1) Measured at V = V
max
and I = 0.8
I
max
2) PTC clamped between points
3) Measured with PTC thermistor mounted in standard EPCOS motor start housing
Electrical specifications and ordering codes
Type
I
max
A
V
max
V
T
ref
C
t
s
1)
s
V
BD
2)
V
R
R
R
R
(V
PTC
2.5 V)
l
r
3)
mA
Ordering code
V
R
= 120 V
RMS
A536
10
200
135
0.30
> 400
10
20%
11
B59536A0135A020
A546
12
180
135
0.45
> 360
4.70
20%
13
B59546A0135A020
A548
12
200
135
0.30
> 400
6.80
20%
12
B59548A0135A020
V
R
= 230 V
RMS
A550
6
355
135
0.25
> 700
33
20%
6.5
B59550A0135A020
A549
7
320
135
0.30
> 640
22
20%
7
B59549A0135A020
A556
8
300
135
0.35
> 600
15
20%
7.5
B59556A0135A020
Motor Starting
Low power consumption
A536 ... A556
Page 3 of 7
Please read Important notes and
Cautions and warnings at the end of this document.
4) All tests with PTC disk mounted in EPCOS housing
Reliability data
Test
4)
Standard
Test conditions
R
25
/R
25
Electrical endurance,
cycling
IEC 60738-1
Room temperature, V
max;
I
max
Number of cycles: 10 000
< 25%
Electrical endurance,
constant
IEC 60738-1
Storage at V
max
/T
op
Test duration : 1000 h
< 25%
Damp heat
IEC 60738-1
Temperature of air: 40
C
Relative humidity of air: 93%
Duration: 56 days
Test according to IEC 60068-2-78
< 20%
Rapid change
of temperature
IEC 60738-1
T
LCT
=
25
C, T
UCT
= 125
C
Number of cycles: 5
Test duration: 30 min
Test according to IEC 60068-2-14, Test Na
< 20%
Vibration
IEC 60738-1
Frequency: 10 - 55 - 10 Hz
Displacement amplitude: 0.75 mm
Test duration: 3 2 h
Test according to IEC 60028-2-6, Test Fc
< 20%
Bump
IEC 60738-1
Pulse shape: half-sine
Acceleration: 40 g
Pulse duration: 6 ms; 6 4000 pulses
Test according to IEC 60068-2-29
< 20%
Climatic sequence
IEC 60738-1
Dry heat: T
UCT
= 125
C
Test duration: 16 h
Damp heat first cycle
Cold: T
LCT
=
25
C
Test duration: 2 h
Damp heat 5 cycles
Tests performed according to
IEC 60068-2-30
< 25%
Motor Starting
Low power consumption
A536 ... A556
Page 4 of 7
Please read Important notes and
Cautions and warnings at the end of this document.
Cautions and warnings
General
EPCOS thermistors are designed for specific applications and should not be used for purposes
not identified in our specifications, application notes and data books unless otherwise agreed
with EPCOS during the design-in-phase.
Ensure suitability of thermistor through reliability testing during the design-in phase. The
thermistors should be evaluated taking into consideration worst-case conditions.
Storage
Store thermistors only in original packaging. Do not open the package before storage.
Storage conditions in original packaging: storage temperature
25
C ... +45
C, relative
humidity
75% annual mean, maximum 95%, dew precipitation is inadmissible.
Avoid contamination of thermistors surface during storage, handling and processing.
Avoid storage of thermistor in harmful environment with effect on function on long-term
operation (examples given under operation precautions).
Use thermistor within 6 months after delivery.
Handling
PTCs must not be dropped. Chip-offs must not be caused during handling of PTCs.
Components must not be touched with bare hands. Gloves are recommended.
Avoid contamination of thermistor surface during handling.
Soldering
Use rosin-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.
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.
Especially 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.
Motor Starting
Low power consumption
A536 ... A556
Page 5 of 7
Please read Important notes and
Cautions and warnings at the end of this document.
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