MRA

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Vishay Mills

Revision: 02-May-12

2

Document Number: 31801

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

DIMENSIONS in inches [millimeters]

MATERIAL SPECIFICATIONS

Element: Copper-nickel alloy or nickel-chrome alloy,

depending on resistance value

Core: Ceramic: Alumina

Coating: Special high temperature silicone

Standard Terminals: Tinned copper

End Caps: Copper alloy

Part Marking: MILLS, model, value, tolerance, date code

DERATING

MODEL

DIMENSIONS in inches [millimeters]

L

± 0.062 [1.57]

D

± 0.031 [0.79]

LD

± 0.002 [0.051]

MRA-05

0.562 [14.27]

0.650 [16.51]

0.167 [4.24]

0.032 [0.813]

MRA-10

0.875 [22.22]

0.975 [24.76]

0.312 [7.92]

0.040 [1.016]

MRA-12

1.188 [30.18]

1.280 [32.51]

0.312 [7.92]

0.040 [1.016]

1.50 [38.10]

min.

L

D

LD

AMBIENT TEMPERATURE IN °C

120

100

80

60

40

20

0

25

- 65

- 50

250

50

350

0

150

Characteristic U

Characteristic V

PERFORMANCE

TEST

CONDITIONS OF TEST

TEST LIMITS

(CHARACTERISTIC U)

(CHARACTERISTIC V)

Dielectric Withstanding

Voltage

± (0.1 % + 0.05

) R

± (0.1 % + 0.05

) R

High Frequency

Vibration

Frequency varied 10 Hz to 2000 Hz, 20 g peak,

2 directions 6 h each

± (0.1 % + 0.05

) R

± (0.2 % + 0.05

) R

High Temperature

Exposure

250 h at + 250 °C for U Characteristic,

+ 350 °C for V Characteristic

± (0.5 % + 0.05

) R

± (4.0 % + 0.05

) R

Load Life

2000 h at rated power, + 25 °C, 1.5 h “ON”, 0.5 h “OFF”

± (0.5 % + 0.05

) R

± (3.0 % + 0.05

) R

Low Temperature

Storage

- 65 °C for 24 h

± (0.2 % + 0.05

) R

± (2.0 % + 0.05

) R

Moisture Resistance

MIL-STD 202 Method 106

± (0.2 % + 0.05

) R

± (2.0 % + 0.05

) R

Shock, Specified Pulse

MIL-STD 202 Method 213, 100 g’s for 6 ms, 10 shocks

± (0.1 % + 0.05

) R

± (0.2 % + 0.05

) R

Thermal Shock

Rated power applied until thermally stable,

then 15 min at - 55 °C

± (0.2 % + 0.05

) R

± (2.0 % + 0.05

) R

Short Time Overload

5 x rated power (5 W smaller),

10 x rated power (7 W and larger) for 5 s

± (0.2 % + 0.05

) R

± (2.0 % + 0.05

) R

Terminal Strength

5 s to 10 s 10 pound pull test;

torsion test - 3 alternating directions, 360 ° each

± (0.1 % + 0.05

) R

± (1.0 % + 0.05

) R