Semi-Precision Power
Semi-Precision Power
Semi-Precision Power
Welwyn Components
Wirewound Resistor
Welwyn Components
Wirewound Resistor
Wirewound Resistor
AS Series
AS Series
AS Series
0.25 to 10 watts
0.25 to 10 watts
0.25 to 10 watts
Tolerance down to 0.5%
Tolerance down to 0.5%
Tolerance down to 0.5%
0.1 ohm to 175K ohms
0.1 ohm to 175K ohms
0.1 ohm to 175K ohms
Resistance wire TCR 20 ppm/C
Resistance wire TCR 20 ppm/C
Resistance wire TCR 20 ppm/C
Electrical Data
Electrical Data
Equivalent Power Rating Commercial Range Non-Inductive Range Available Resistance
Equivalent Power Rating Commercial Range Non-Inductive Range Available Resistance
MIL-R-26 (watts) (ohms) (ohms) (ohms)
MIL-R-26 (watts) (ohms) (ohms) (ohms)
Type Style 125C 25C Min. Max. Min. Max. 0.5%, 1% 3%, 5%
Type Style 125C 25C Min. Max. Min. Max. 0.5%, 1% 3%, 5%
1
AS- /4 RW81 0.5 1 0.1 1.0K * * 1-1K 0.1-1K
1
AS- /4 1 RW81 0.5 1 0.1 1.0K * * 1-1K 0.1-1K
AS- /2 0.5 1 0.1 6.0K * * 1-6K 0.1-6K
1
AS- /2 0.5 1 0.1 6.0K * * 1-6K 0.1-6K
AS-1 RW70U 1 2 0.1 7.5K 0.1 3.8K 1-7.5K 0.1-7.5K
AS-1 RW70U 1 2 0.1 7.5K 0.1 3.8K 1-7.5K 0.1-7.5K
AS-1C 1 2 .05 2K * * 1-2K .05-2K
AS-1C 1 2 .05 2K * * 1-2K .05-2K
AS-2 RW-69V/ 2 3 0.1 20K 0.5 10K 1-20K 0.1-20K
AS-2 RW-69V/ 2 3 0.1 20K 0.5 10K 1-20K 0.1-20K
RW79U
RW79U
AS-2B 3 4 0.1 24K 0.5 12K 1-24K 0.1-24K
AS-2B 3 4 0.1 24K 0.5 12K 1-24K 0.1-24K
AS-2C 2 3 0.1 18K 0.2 7.5K 1-18K 0.1-18K
AS-2C 2 3 0.1 18K 0.2 7.5K 1-18K 0.1-18K
AS-3 3 5 0.1 30K 0.5 15K 1-30K 0.1-30K
AS-3 3 5 0.1 30K 0.5 15K 1-30K 0.1-30K
AS-5 RW74U/ 5 7 0.1 60K 0.8 30K 1-60K 0.1-60K
AS-5 RW74U/ 5 7 0.1 60K 0.8 30K 1-60K 0.1-60K
RW67U
RW67U
AS-7 7 9 0.1 90K 1.0 45K 1-90K 0.1-90K
AS-7 7 9 0.1 90K 1.0 45K 1-90K 0.1-90K
AS-10 RW68V/ 10 14 0.1 175K 3.0 50K 1-175K 0.1-175K
AS-10 RW68V/ 10 14 0.1 175K 3.0 50K 1-175K 0.1-175K
RW78U
RW78U
Inductance of AS-1/2 is less than 1H at 1MHz. * Typical inductance of AS-1C <5ohms is <1H.
Inductance To order of AS-1/2 non-inductive is less than types, 1H add at the 1MHz.prefix N. Example: NAS-1, NAS-2C, * etc.Typical Lower inductance values available of AS-1C upon <5ohms request.is <1H.
To order non-inductive types, add the prefix N. Example: NAS-1, NAS-2C, etc. Lower values available upon request.
Physical Data
Physical Data
Dimensions (mm)
Dimensions (mm)
Type A 0.81 B (max) C (max) D (Lead Diameter)
1.50 min.
A
Type A 0.81 B (max) C (max) D (Lead Diameter)
1
AS- /4 6.4 2.4 7.9 0.5 (38.1)
1.50 min.
A
1
D B
AS- /4 1 6.4 2.4 7.9 0.5 (38.1)
AS- /2 7.9 2.4 9.5 0.5
D B
1
AS- /2 7.9 2.4 9.5 0.5
AS-1 9.3 3.2 10.9 0.5 0.64
C
AS-1 9.3 3.2 10.9 0.5 0.64
AS-1C 6.5 2.9 7.7 0.64 0.8 C
Please note lead length dimension change on the following
AS-1C 6.5 2.9 7.7 0.64 0.8
AS-2 12.2 6.3 15.2 0.8
two items only:
Please note lead length dimension change on the following
AS-2 12.2 6.3 15.2 0.8
AS-2B 13.7 5.6 16.6 0.8 AS-2B 33.0mm (min)
two items only:
AS-2C 33.0mm (min)
AS-2B 13.7 5.6 16.6 0.8 AS-2B 33.0mm (min)
AS-2C 11.0 4.0 15.1 0.8
AS-2C 33.0mm Note: (min)
AS-2C 11.0 4.0 15.1 0.8
AS-3 17.5 7.2 20.6 1.0
Coating and marking is resistant to normal freon
Note:
degreasing.
AS-3 17.5 7.2 20.6 1.0
Coating and marking is resistant to normal freon
AS-5 22.2 8.8 24.9 1.0
Consult factory for special requirements.
degreasing.
AS-5 22.2 8.8 24.9 1.0
AS-7 31.8 8.8 35.0 1.0
AS marking available in Alpha Numeric or Colourbanding -
Consult factory for special requirements.
identification available.
AS-7 31.8 8.8 35.0 1.0
AS marking available in Alpha Numeric or Colourbanding -
AS-10 46.0 9.8 49.2 1.0
identification available.
AS-10 46.0 9.8 49.2 1.0
* Leads are solder plated. AS-1C leads are copper. All others are 40% conductivity copper sheathed steel.
* Leads are solder plated. AS-1C leads are copper. All others are 40% conductivity copper sheathed steel.
General Note
Welwyn Components reserves the right to make changes in product specification without notice or liability.
General Note
General Note
All information is subject to Welwyns own data and is considered accurate at time of going to print. A subsidiary of
Welwyn Components reserves the right to make changes in product specification without notice or liability.
TT electronics reserves the right to make changes in product specification without notice or liability.
TT electronics plc
All information is subject to Welwyns own data and is considered accurate at time of going to print. A subsidiary of
All information is subject to TT electronics own data and is considered accurate at time of going to print.
Welwyn Components Limited Bedlington, Northumberland NE22 7AA, UK
TT electronics plc
www.bitechnologies.com www.irctt.com www.welwyn-tt.com
Telephone: +44 (0) 1670 822181 Facsimile: +44 (0) 1670 829465 Email: info@welwyn-tt.com Website: www.welwyn-tt.com Issue D 03.06
Welwyn Components Limited Bedlington, Northumberland NE22 7AA, UK
TT electrTelephone: +44 onics plc(0) 1670 822181 Facsimile: +44 (0) 1670 829465 Email: info@welwyn-tt.com Website: www.welwyn-tt.com Issue D 03.06
91
10. 11
91Semi-Precision Power
Semi-Precision Power
Wirewound Resistor
Wirewound Resistor
AS Series
Welwyn Components
AS Series
Power Derating Temperature Rise @ 25C
275
200
AS-7, 10
250
AS-1/4, 1/2, 1, 1C
AS-2A, 2C
175
AS-3, AS-5
AS-3, 2
200
AS-2B
150 AS-2A, 2C
AS-2C
AS-5, 10
150
AS-1/2
125
AS-2B
100
100
AS-1/4
AS-7
50
75
25
0
25 75 125 175 225 275 0 40 80 120 160 200
Ambient Temperature (C) Percent of 25C Power Rating
Temperature Rise @ 125C Selected Pulse-Handling Capability @ 125C
275
14
AS-7, 10
AS-2A
12
250
AS-3, AS-5 AS-3
AS-2
AS-2B
AS-2
10
AS-2A, 2C
AS-1/2
8
200 AS-2B
6
AS-2C
AS-1/4
4
AS-1
150
2
AS-1/2
AS-1/4
0
125
0 40 80 120 160 200 0.1 0.2 0.5 1 2 5 10
Resistance (ohms)
Percent of 125C Power Rating
Environmental Testing at 25C
Test Condition Max R
Load Life 1000 hours 1.0%
Moisture Resistance 1.0%
Temperature Cycle 0.5%
Short Time Overload 0.5%
Low Temperature Operation 0.5%
Solder Heat 0.25%
Shock 0.5%
Vibration 0.5%
General Note
TT electronics reserves the right to make changes in product specification without notice or liability.
All information is subject to TT electronics own data and is considered accurate at time of going to print.
www.bitechnologies.com www.irctt.com www.welwyn-tt.com
Welwyn Components Limited Bedlington, Northumberland NE22 7AA, UK
TT electrTelephone: +44onics plc (0) 1670 822181 Facsimile: +44 (0) 1670 829465 Email: info@welwyn-tt.com Website: www.welwyn-tt.com Issue D 03.06
10. 11
92
Hot Spot Temperature (C) Percent of 125C Power Rating
Hot Spot Temperature (C)
Energy (watts-second)