RWM

www.vishay.com

Vishay Sfernice

Revison: 15-Apr-14

2

Document Number: 50008

THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT

OVERLOAD

Heavy overloads can be endured in the form of short pulses

< 0.1 s. Particular requirements should be submitted to

Vishay Sfernice, specifying peak voltage, cycle and

environmental conditions.

RECOMMENDATIONS FOR USE

Since these components are high dissipation power

resistors, customers are advised to use a high melting point

solder.

For low ohmic values, the measurement becomes critical

and the connecting wires resistance is to be included. The

value is measured at 5 mm from the resistor body.

Group Mounting



In a still atmosphere, a distance between axes equal to five

times the resistor’s diameter is recommended.

Cabinet Mounting

• Unventilated box: Dissipation should be reduced (see

dimensional drawing).

• Forced

ventilation:

If

conditions

are

appropriate,

dissipation may be doubled or even trebled.

• In any case: The surface temperature at the hottest point

should not exceed 450 °C.

These aspects should be considered by the end user.

TECHNICAL SPECIFICATIONS

VISHAY SFERNICE SERIES

AND STYLE

RWM

4 x 10

RWM

4 x 22

RWM

5 x 26

RWM

6 x 22

RWM

8 x 26

RWM

6 x 34

RWM

8 x 34

RWM

8 x 45

RWM

10 x 45

RWM

10 x 64

RWM

10 x 65

Power Rating

at + 70 °C

2.6 W

4.5 W

6 W

6 W

7 W

7 W

9.5 W

9.5 W

21 W

21 W

25.8 W

at + 25 °C

3 W

5 W

7 W

7 W

8 W

8 W

11 W

11 W

25 W

25 W

30 W

With Surface

Temp.



 + 450 °C

5.5 W

7 W

10 W

10 W

10 W

12 W

14 W

20 W

25 W

25 W

30 W

Ohmic Range in Relation to

Tolerance ± 5 % E24 Series

0.1



10 k



0.1



16 k



0.1



27 k



0.1



39 k



0.1



27 k



0.33



36 k



0.33



36 k



0.47



62 k



0.47



62 k



0.68



100 k



0.68



100 k



Qualified Ohmic Range



NF C 83-210

0.1



10 k



0.1



6.8 k



0.15



10 k



0.15



39 k



-

0.33



15 k



-

0.47



33 k



--

-

Limiting Element Voltage

120 V

300 V

350 V

350 V

500 V

500 V

650 V

650 V

800 V

800 V

800 V

Critical Resistance

4.8 k



-

18.8 k

 17.5 k

-

31 k



-38 k



25.6 k

 25.6 k 21.3 k

PERFORMANCE

CECC 40201 - EN 140-201

TYPICAL DRIFTS

TESTS

CONDITIONS

REQUIREMENTS

Short Time Overload

25 °C ambient

± (2 % + 0.1

)

± (0.5 % + 0.05

)

Temperature Cycling



(5 cycles)

- 55 °C + 200 °C

± (1 % + 0.05

)

± (0.5 % + 0.05

)

Humidity (Steady State)

56 days

40 °C ambient - R.H. 95 %

± (5 % + 0.1

)

± (0.5 % + 0.05

)

Terminal Strength

Tensile test: 20 N

2 successive bending

2 full rotations of 180°

± (1 % + 0.05

)

± (0.1 % + 0.05

)

Load Life

90’/30’ cycle

25 °C ambient

± (5 % + 0.1

)

± (1.5 % + 0.05

)

ELECTRICAL SPECIFICATIONS

Tolerance

Standard

± 5 % (NI ± 10 %)

On request

± 1 % and ± 2 % (NI ± 5 %)

Temperature Coefficient

+ 75 ppm/°C typical

Dielectric Withstanding Voltage NF EN140000

Inductance

Non inductive (Ayrton-Perry) winding available