RXE(7) 1/15/99 11:44 AM Page 165
RXE
Selection Guide
and Product Data
This section has two parts:
• A Selection Guide that walks you through the process of
selecting the correct RXE device for a circuit.
• Product Data that outlines electrical characteristics,
physical characteristics, agency recognitions, environmental
specifications, component layouts, tape and reel specifications,
and ordering information for RXE devices.
RXE Selection Guide
Follow these seven steps to select a PolySwitch RXE device for
a circuit:
1. Define the operating parameters for the circuit.
These include:
• Maximum ambient operating temperature
• Normal operating current
• Maximum operating voltage (RXE is 60 V maximum)
• Maximum interrupt current
2. Select the RXE device that accommodates the circuit’s maximum
ambient operating temperature and normal operating current.
3. Compare the RXE device’s maximum operating voltage and
maximum interrupt current with the circuit’s to be sure the circuit
does not exceed the device ratings.
4. Check the RXE device’s time-to-trip to be sure it will protect the
circuit.
5. Verify that the circuit’s ambient operating temperatures are within the
RXE device’s operating temperature range.
6. Verify that the RXE device’s dimensions fit the application’s space
considerations.
7. Independently evaluate and test the suitability and performance
of the RXE device in the application.
®
4
®
TUV Rheinland
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RXE Devices
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RXE
Radial Leaded
1.
Define the circuit’s operating parameters.
Fill in the following information about the circuit:
Maximum ambient operating temperature
Normal operating current
Maximum operating voltage (RXE is 60 V max.)
Maximum interrupt current
________________
________________
________________
________________
2.
Select the PolySwitch RXE device that will accommodate the
circuit’s maximum ambient operating temperature and
mal operating current.
nor-
Look across the top of the table on the next page to find the tempera-
ture that most closely matches the circuit’s maximum ambient operat-
ing temperature. Look down that column to find the value equal to or
greater than the circuit’s normal operating current. Now look to the far
left of that row to find the part number for the RXE device that will best
accommodate the circuit.
The thermal derating curve located on the next page is a normalized
representation of the data in the table located on the same page.
4
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RXE
I
Hold
vs. temperature
Maximum ambient
–40°
–20°
0.16
0.14
0.26
0.23
0.31
0.27
0.39
0.34
0.47
0.41
0.62
0.54
0.78
0.68
1.01
0.88
1.16
1.02
1.40
1.22
1.71
1.50
2.09
1.84
2.48
2.18
2.87
2.52
3.88
3.40
4.65
4.08
5.81
5.10
operating temperatures (°C)
0°
20°
40°
50°
0.12
0.10
0.08
0.07
0.20
0.17
0.14
0.12
0.24
0.20
0.16
0.14
0.30
0.25
0.20
0.18
0.36
0.30
0.24
0.22
0.48
0.40
0.32
0.29
0.60
0.50
0.41
0.36
0.77
0.65
0.53
0.47
0.89
0.75
0.61
0.54
1.07
0.90
0.73
0.65
1.31
1.10
0.89
0.79
1.61
1.35
1.09
0.97
1.90
1.60
1.30
1.15
2.20
1.85
1.50
1.33
2.98
2.50
2.03
1.80
3.57
3.00
2.43
2.16
4.46
3.75
3.04
2.70
Radial Leaded
Part
number
RXE010
RXE017
RXE020
RXE025
RXE030
RXE040
RXE050
RXE065
RXE075
RXE090
RXE110
RXE135
RXE160
RXE185
RXE250
RXE300
RXE375
60°
0.06
0.11
0.13
0.16
0.19
0.25
0.32
0.41
0.47
0.57
0.69
0.85
1.01
1.17
1.58
1.89
2.36
70°
0.05
0.09
0.11
0.14
0.16
0.22
0.27
0.35
0.41
0.49
0.59
0.73
0.86
1.00
1.35
1.62
2.03
85°
0.04
0.07
0.08
0.10
0.12
0.16
0.20
0.26
0.30
0.36
0.44
0.54
0.64
0.74
1.00
1.20
1.50
4
Thermal derating curve
200
Percent of rated hold
and trip current
150
100
50
0
–40
–20
0
20
40
60
80
Device’s ambient temperature (°C)
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RXE Devices
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RXE
Radial Leaded
3.
Compare maximum operating voltages and maximum
interrupt currents.
Look down the first column of the table below to find the part number
you selected in Step 1. Look to the right in that row to find the device’s
maximum operating voltage (V max.) and maximum interrupt current
(I max.).
Compare both ratings with the circuit’s to be sure the circuit’s ratings
do not exceed those of the RXE device.
Maximum device voltages and currents
Part
number
RXE010
RXE017
RXE020
RXE025
RXE030
RXE040
RXE050
RXE065
RXE075
RXE090
RXE110
RXE135
RXE160
RXE185
RXE250
RXE300
RXE375
V max.
(volts)
60
60
60
60
60
60
60
60
60
60
60
60
60
60
60
60
60
I max.*
(amps)
40
40
40
40
40
40
40
40
40
40
40
40
40
40
40
40
40
4
* Devices may withstand higher interrupt current at lower voltages.
Each application will need to be individually qualified.
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RXE
4.
Determine time-to-trip.
Radial Leaded
Time-to-trip is the amount of time it takes for a device to switch to a
high-resistance state once a fault current has been applied across the
device.
Identifying the RXE device’s time-to-trip is important in order to provide
the desired protection capabilities. If the device you choose trips
too fast, undesired or nuisance tripping will occur. If the device trips too
slowly, the components being protected may be damaged before the
device switches to a high-resistance state.
The chart below shows the typical time-to-trip at 20°C for each
PolySwitch RXE device. For example, the chart indicates that the
typical time-to-trip for RXE050 at 5 A is 0.3 second.
On the chart below, find the typical time-to-trip for the RXE device you
selected. If the RXE device’s time-to-trip is too fast or too slow for the
circuit, go back to Step 2 and choose an alternate device.
Typical time-to-trip at 20°C
4
A
=
B
=
C
=
D
=
E
=
F
=
G
=
H
=
I
=
J
=
K
=
L
=
M
=
N
=
O
=
P
=
Q
=
RXE010
RXE017
RXE020
RXE025
RXE030
RXE040
RXE050
RXE065
RXE075
RXE090
RXE110
RXE135
RXE160
RXE185
RXE250
RXE300
RXE375
1000
A
B CDE F G H I J K L M N OPQ
100
10
Time-to-trip (s)
1
0.1
0.01
0.001
0.1
1
Fault current (A)
10
100
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RXE Devices
169
