General Purpose
Wirewound Resistors
SPP Series
Welwyn Components
•
•
•
•
0R1 to 2K4 ohms
Positive high TC’s upon request
Weldable and solderable magnetic leads
Lower ranges available - contact factory
Electrical Data
Type
Resistance range
Standard Tolerance
ohms
±%
SPP-1
0R1 - 1K2*
5, 10
1 @ 85°C
0.75 @ 105°C
Power Rating
watts
0.5 @ 125°C
Derating to 0 @ 160°C
Load Life Stability
Max. Continuous Working Voltage
Min. Insulation Resistance - Dry
Min. Insulation Resistance - Wet
Min. Dielectric Withstanding Voltage
Current Noise
Temperature Rise at Rated Load, 25°C Ambient
Approx. 150°C
watts
1 @ 85°C ± 10%
SPP-2
0R1 - 2K4
5, 10
2 @ 85°C
1 @ 140°C
-
-
2 @ 85°C ± 10%
√PR
10,000 megohm
100 megohm
600 volts RMS
Negligible
Approx. 200°C
Approx. 225°C
SPP-3
0R1 - 2K4
5, 10
3 @ 85°C
2 @ 145°C
1 @ 190°C
-
3 @ 85°C ± 10%
Note: Unless specified otherwise standard test centres are 1
3
/
4
inches.
Physical Data
Dimensions (inches)
Type
SPP-1
SPP-2
SPP-3
A max
0.400
0.570
0.570
B max
0.148
0.170
0.170
C±0.002
0.032
0.032
0.032
1.125 min
B
C
A
max.
Fuse/Pulse Applications
SPP resistors normally fuse in less than one minute with five
to ten times rated wattage depending on the range. By
modifying the windings, using a different wire size or type,
they can be made to fuse much faster.
On the other hand, by using larger wire diameters and higher
melt temperature alloys they can handle from five to fifty
times overloads of film resistors depending on the range.
General Note
Welwyn Components reserves the right to make changes in product specification without notice or liability.
All information is subject to Welwyn’s own data and is considered accurate at time of going to print.
A subsidiary of
TT electronics plc
Issue B · 03.02
© Welwyn Components Limited
· Bedlington, Northumberland NE22 7AA, UK
Telephone: +44 (0) 1670 822181 · Facsimile: +44 (0) 1670 829465 · Email: info@welwyn-tt.com · Website: www.welwyn-tt.com
97
General Purpose
Wirewound Resistors
SPP Series
Welwyn Components
Performance Data
Maximum Limits
Temperature Coefficient
SPP-1
SPP-2
SPP-3
Thermal Shock
Low Shock
Short Time Overload
Commercial Short Time Overload
Resistance to Solder Immersion
Solderability
Moisture Resistance
Life Test
Test Method
±600/°C 0.10Ω-0.91Ω
±300/°C 1.0Ω-1200Ω
±600/°C 0.10Ω-0.91Ω
±300/°C 1.0Ω-2400Ω
±600/°C 0.10Ω-0.91Ω
±600/°C 1.0Ω-2400Ω
±5%
±5%
±5%
±5%
±3%
95% minimum coverage
±5%
±5%
EIA Specification RS-344
Power Derating:
100
Percent Rated Power
SPP-3
SPP-1, 2
Temperature Rise:
Temperature Rise (°C)
300
200
100
SPP-1
0
0
20
40
60
80
100
SPP-3
SPP-2
80
60
40
20
0
0
50
100
150
200
250
300
Ambient Temperature (°C)
Percent Rated Power
Ordering Procedure
Example: SPP1 at 100 ohms and 5% tolerance tape packed on a reel
–
SPP1
–
100RJ
I
Type
Value (use IEC62 code)
Tolerance (use IEC62 code)
J
5%
K
10%
Packing
I
Tape
Standard
© Welwyn Components Limited
Bedlington, Northumberland NE22 7AA, UK
Telephone: +44 (0) 1670 822181 · Facsimile: +44 (0) 1670 829465 · Email: info@welwyn-tt.com · Website: www.welwyn-tt.com
98
Issue B · 03.02
