Datasheet

PTCCL - 265 V Series
www.vishay.com
Vishay BCcomponents
Revision: 21-Sep-15
3
Document Number: 29087
For technical questions, contact: [e-mail]
THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT
ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc?91000
VOLTAGE DERATING AS A FUNCTION OF AMBIENT TEMPERATURE
MAXIMUM OVERLOAD CURRENT I
ol max.
DERATING AS A FUNCTION OF VOLTAGE
I
ol max.
as stated in the electrical data and ordering information tables, is the maximum overload current that may flow through
the PTC when passing from the low ohmic to high ohmic state at rated voltage.
When other voltages are present after tripping, the I
ol max.
value can be derived from the above I
max.
as a function of voltage
graph. Voltages below V
rated
will allow higher overload currents to pass the PTC.
TYPICAL TRIP-TIME AS A FUNCTION OF TRIP CURRENT RATIO
Trip-Time or Switching Time (t
s
)
To check the trip-time for a specific PTC, refer to the Electrical Data and Ordering Information tables for the value I
nt
. Divide the
overload or trip current by this I
nt
and you realize the factor I
t
/I
nt
. This rule is valid for any ambient temperature between 0 °C
and 70 °C. Adapt the correct non-trip current with the appropriate curve in the Current Deviation as a Function of the Ambient
Temperature graph. The relationship between the It/Int factor and the switching time is a function of the PTC diameter; see the
above graphs.
Example
What will be the trip-time at I
ol
= 0.8 A and T
amb
= 50 °C of a thermistor type PTCCL09H171HBE; 22 Ω; Ø D
max.
= 8.5 mm:
I
nt
from the table: 170 mA at 25 °C
I
nt
: 170 x 0.87 = 148 mA (at 50 °C)
Overload current = 0.8 A; factor I
t
/I
nt
: 0.8/0.148 = 5.40. In the Typical trip-time as a function of trip current ratio graph, at the
8.5 mm line and I
t
/I
nt
= 5.40, the typical trip-time is 3.0 s.
120
100
40
80
60
0
-25-50 0 25 50 75 200
T
amb
(°C)
20
100 125 150 175
V
max.
(%)
100 120 150
200
100
150
80
I
ol max.
(%)
7050400
V
rated
(%)
Curve 1: Ø D
max.
= 20.5 mm
Curve 2: Ø D
max.
= 16.5 mm
Curve 3: Ø D
max.
= 12.5 mm
Curve 4: Ø D
max.
= 10.5 mm
Curve 5: Ø D
max.
= 8.5 mm
Curve 6: Ø D
max.
= 7.0 mm
Curve 7: Ø D
max.
= 5.0 mm
Measured in accordance with
“IEC 60 738”.
10
2
10
1
10
-1
t
s
12 4 6 8 10 12 14 16
I
t
/I
nt
10
3
(7)
(5)
(6)
(3)
(4)
(1)
(2)