User Manual

RWST
Fixed Wirewound High Power Vitreous Resistors
Electrical Traction Model
Vishay Sfernice
Document Number: 50017 For technical questions, contact: [e-mail]
www.vishay.com
Revision: 23-Oct-06 62
MECHANICAL SPECIFICATIONS
Mechanical Protection Vitreous enamel
Resistive Element Ni-Cr wire
Connections CS supporting collars
AN Collar or B on Request
Average Unit Weight 225 to 2200 g
ENVIRONMENTAL SPECIFICATIONS
Temperature Limits - 55 °C + 450 °C
Climatic Category - 55 °C/+ 200 °C/56 days
NON INDUCTIVE WINDING
For high frequencies, low self induction resistors are available with special windings.
RWSTNI designation.
ELECTRICAL SPECIFICATIONS
Resistance Range
2.7 Ω to 430 kΩ
E12-E24 preferred series values)
Resistance Tolerance
Standard ± 5 %
Power Rating 95 W to 800 W at 25 °C
Temperature Coefficient 75 ppm/°C (typical)
Shelf Life 0.1 % year (typical)
PERFORMANCE
TESTS CONDITIONS REQUIREMENTS
TYPICAL VALUES AND
DRIFTS
Short Time Overload
10 Pr during 5 s
Voltage limited at < 5000 V
2 % or 0.05 Ω 0.5 %
Climatic Sequence - 55 °C + 200°C
2 % or 0.05 Ω
Insulation resistance 100 MΩ
0.5 %
Humidity
(Steady State)
56 days
95 % relative humidity
3 % or 0.05 Ω
Insulation resistance 100 MΩ
0.5 %
Thermal Shock
Load at 100 % Pr followed by cold
temperature exposure at - 55 °C/15’
2 % or 0.05 Ω 0.5 %
Shock
severity 50 A
9 shocks/each side
1 % or 0.05 Ω 0.25 %
Vibration severity 55B 1 % or 0.05 Ω 0.25 %
Terminal Strength AN
B
Traction 40 Ncm
Torque 60 Ncm
1 % or 0.05 Ω 0.5 %
Load Life
90’/30’ cycle
1000 h at Pr 25 °C
5 %
1000 h 1 %
5000 h 2 %
SPECIAL FEATURES
RWST STYLE 25 x 138 25 x 168 30 x 250 40 x 370 50 x 373
Designation NF C 93-214 - RB 25 × 168 RB 30 × 250 - -
Power Rating at 25 °C 95 W 160 W 280 W 500 W 700 W
Maximum Power
Rating at 25 °C P max.
110 W 180 W 320 W 600 W 800 W
Ohmic Range
(E12, E24 series)
2.7 Ω 82 kΩ 2.7 Ω 100 kΩ 4.7 Ω 220 kΩ 8.2 Ω 360 kΩ 12 Ω 430 kΩ
Limiting Element Voltage 1400 V 1900 V 3000 V 4500 V 5000 V
Critical Resistance 18 kΩ 20 kΩ 30 kΩ 36 kΩ 30 kΩ
MODEL AND
STYLE
RWSTNI
25 × 138
RWSTNI
25 × 168
RWSTNI
30 × 250
RWSTNI
40 × 370
RWSTNI
50 × 373
OHMIC RANGE
(E12 SERIES)
22 Ω
2.5 kΩ
22 Ω
4 kΩ
120 Ω
6.8 kΩ
120 Ω
8.2 kΩ
150 Ω
8.2 kΩ