Metal Oxide Resistors, High Power
WK/WR
Vishay Draloric
www.vishay.com For technical questions, contact: ff1aresistors@vishay.com Document Number: 20128
156 Revision: 14-Sep-07
FEATURES
•Rugged metal oxide film
•Lead (Pb)-free solder contacts
•Pure tin plating provides compatibility with
lead (Pb)-free and lead containing soldering processes
•Compatible with "Restriction of the use of Hazardous
Substances" (RoHS) directive 2002/95/EC (issue 2004)
•High power dissipation in small size (1 W/0207 size to
4 W/0922 size)
•High temperature coating (up to 200 °C), nonflammable
Notes:
• Coating: green
• Marking: WR4 has color code marking does not have a TCR band. WR5 and WK8 are printed marked. For further information see appropriate
catalog or web page.
Notes:
(1) Rated Voltage
(2) For values < 10R the upper limiting temperature is 155 °C. The power rating is correspondingly lower and can be caculated by Rth
STANDARD ELECTRICAL SPECIFICATIONS
MODEL SIZE POWER RATING
P70 °C
W
LIMITING ELEMENT
VOLTAGE MAX.
V≅
TEMPERATURE
COEFFICIENT
ppm/K
TOLERANCE
%
RESISTANCE
RANGE
Ω
E-SERIES
WK2 0207 1.0 500 ± 50 ± 1 4R7 - 1M0 96
WK2 0207 1.0 500 ± 100 ± 2
± 5 1R0 - 1M0
R18 - 10M 48
24
WK2 0207 1.0 500 ± 200 ± 5 0R18 - 10M 24
WR4 0414 2.0 500 ± 200 ± 2
± 5 1R0 - 1M0
R18 - 10M 48
24
WR5 0617 3.0 750 ± 200 ± 2
± 5 1R0 - 100K
R22 - 560K 48
24
WK8 0922 4.0 750 ± 200 ± 2
± 5 1R0 - 68K
R22 - 100K 48
24
TECHNICAL SPECIFICATIONS
PARAMETER UNIT WK2 WR4 WR5 WK8
Rated Dissipation at 70 °C W 1.0 2.0 3.0 4.0
Limiting Element Voltage (1) V≅500 500 750 750
Insulation Voltage (1 min) Veff > 500 > 500 > 500 > 500
Thermal Resistance (max) K/W ≤ 140 ≤ 100 ≤ 70 ≤ 60
Insulation Resistance Ω> 109
Voltage Coefficient 1/V < 10-7
Thermal Time Constant s14 20 35 70
Category Temperature Range (2) °C - 55 to + 200
Terminal Strength, axial N > 60 > 80 > 80 > 80
Failure Rate 10-8/h < 1
Weight g 0.2 0.7 1.5 3.5
P x R
WK/WR
Metal Oxide Resistors, High Power Vishay Draloric
Document Number: 20128 For technical questions, contact: ff1aresistors@vishay.com www.vishay.com
Revision: 14-Sep-07 157
Note:
(1) Please refer to table PACKAGING.
PART NUMBER AND PRODUCT DESCRIPTION WK2-SERIES
PART NUMBER: WK202070C1001FD500
MODEL/SIZE SPECIAL CHARACTER TCR VALUE TOLERANCE PACKAGING SPECIAL
WK20207 0 = neutral C = ± 50 ppm/K
B = ± 100 ppm/K
A = ± 200 ppm/K
3 digit value
1 digit multiplier
MULTIPLIER
7 = *10-3
8 = *10-2
9 = *10-1
0 = *100
1 = *101
2 = *102
3 = *103
4 = *104
5 = *105
6 = *106
F = ± 1 %
G = ± 2 %
J = ± 5 %
22 = A2
25 = A5
D5 = R5
up to 2 digits
00 = standard
PRODUCT DESCRIPTION: WK2 50 1K0 1 % R5
WK2 50 1K0 1 % R5
MODEL TCR RESISTANCE VALUE TOLERANCE PACKAGING (1)
WK2 ± 50 ppm/K
± 100 ppm/K
± 200 ppm/K
49K9 = 49.9 kΩ
50R1 = 50.1 Ω
1K0 = 1.0 kΩ
± 1 %
± 2 %
± 5 %
A2
A5
R5
PART NUMBER AND PRODUCT DESCRIPTION WK8-SERIES
PART NUMBER: WK80922001000J5C00
MODEL/SIZE SPECIAL CHARACTER TCR VALUE TOLERANCE PACKAGING SPECIAL
WK80922 0 = neutral 0 = standard 3 digit value
1 digit multiplier
MULTIPLIER
7 = *10-3
8 = *10-2
9 = *10-1
0 = *100
1 = *101
2 = *102
3 = *103
4 = *104
5 = *105
G = ± 2 %
J = ± 5 % 5C = AC
G1 = R1 up to 2 digits
00 = standard
PRODUCT DESCRIPTION: WK8 100R 5 % AC
WK8 100R 5 % AC
MODEL RESISTANCE VALUE TOLERANCE PACKAGING (1)
WK8 100R = 100 Ω
47K = 47 kΩ
± 2 %
± 5 % AC
R1
02 10 1FD0K2 5W 700 C
09 10 0J50K8 CW 202 0
WK/WR
Vishay Draloric Metal Oxide Resistors, High Power
www.vishay.com For technical questions, contact: ff1aresistors@vishay.com Document Number: 20128
158 Revision: 14-Sep-07
Note:
(1) Please refer to table PACKAGING.
• The PART NUMBER shown above is to facilitate the unified part numbering system for ordering products.
DIMENSIONS
Notes:
(1) 9 mm for WR5/WK8
• Taping in acc. with IEC60286-1
• D and L measured in acc. with IEC60294
• d according to IEC60301
PART NUMBER AND PRODUCT DESCRIPTION WR-SERIES
PART NUMBER: WR404140A1001GFE00
MODEL/SIZE SPECIAL CHARACTER TCR VALUE TOLERANCE PACKAGING SPECIAL
WR40414
WR50617 0 = neutral A = ± 200 ppm/K 3 digit value
1 digit multiplier
MULTIPLIER
7 = *10-3
8 = *10-2
9 = *10-1
0 = *100
1 = *101
2 = *102
3 = *103
4 = *104
5 = *105
6 = *105
G = ± 2 %
J = ± 5 % 41 = A1 G73
51 = A1 G77
FE = RE G73
GP = RP
up to 2 digits
00 = standard
PRODUCT DESCRIPTION: WR4 1K0 2 % RE
WR4 1K0 2 % RE
MODEL RESISTANCE VALUE TOLERANCE PACKAGING (1)
WR4
WR5 1K0 = 1.0 kΩ
51R0 = 51.0 Ω
± 2 %
± 5 % A1 (G73)
A1 (G77)
RE (G73)
RP
PACKAGING
MODEL
REEL BOX
PIECES/REEL CODE MIN. ORDER QTY
PACKAGING UNITS PIECES/BOX CODE MIN. ORDER QTY
PACKAGING UNITS
WK2 5000 R5 1 5000
2000
A5
A2
1
1
WR4 2500 RE 2 1000 A1 2
WR5 1500 RP 2 1000 A1 2
WK8 1000 R1 2 500 AC 2
L1
Ld
D
B
e
6 mm (1)
MODEL
DIMENSIONS [in millimeters]
DLL
1max Bde
WK2 2.5 - 0.5 6.3 - 0.5 8.0 53 ± 1 0.6 7.5
WR4 4.1 - 0.5 12.0 - 1.5 16.0 73 ± 1 0.8 15.0
WR5 6.0 - 0.5 16.5 - 1.5 20.0 77 ± 1 0.8 17.5
WK8 9.0 - 0.5 20.0 - 1.5 24.0 77 ± 1 0.8 22.5
04 10 1GF0R4 EW 401 A
WK/WR
Metal Oxide Resistors, High Power Vishay Draloric
Document Number: 20128 For technical questions, contact: ff1aresistors@vishay.com www.vishay.com
Revision: 14-Sep-07 159
120
100
80
60
40
20
0- 55 0 40 80 120 160 200 240 280 320 360
70 AMBIENT TEMPERATURE IN °C
DERATING
%
NI
REWOP
D
ET
A
R
300
250
200
150
100
50
00 1.0 2.0 3.0 4.0 5.0
POWER IN W
TEMPERATURE RISE
C
°
N
I ESIR
E
R
UT
A
RE
P
M
E
T
WR4WK2
WK2
WR4
WR5
WK8
WR5
WK8
1000
100
10
1
0.1
WR 5
WR 4
WK 8
WK 2
10
WR 5
WR 4
WK 8
WK 2
10-5 10-4
100
10-1 10010
101
10-1
10-2 100
10-3
102
10-1
10-5 10-4 10-3 10-2
103
]W[
P
GNITAR REWOP
]
W[
GNIT
A
R REWOP
PULSE RATING O
Secondary Conditions:
a) ϑ
b)ϑu≤ 70 °C
c) ÛMAX see diagram below
d) ~ 10R
Secondary Conditions:
a) ≤ 70 (permissible constant
power at ϑu = 70 °C)
b)ϑu≤ 70 °C
c) ÛMAX see diagram below
d) ~ 10R
P
SQUARE PULSE i [s]
t
SQUARE PULSE i [s]
t
P
PULSE RATING ≤ 70
PP
P
PP
NON-LINEARITY
]Bd[ 3A YTIRAENIL-NON
130
120
110
100
90
1K 10K 100K 1M 10M
RESISTANCE VALUE IN
WR4
WR5/WK8
CURRENT NOISE
10
1
0.1
0.01
ESION TNE
R
RU
CµV/V
WR4
10K 100K 1M 10M
RESISTANCE VALUE IN
2000
1000
0
WR 5/WK8
WR 4
MAX. PULSE VOLTAGE
WK 2
10-5 10-4 10-2
10-3 10-1 10
100
WR5/WK8
Ω
Ω
Secondary Conditions:
a) MAX see diagram below
b) See diagram below
c)
ϑu ≤ 70 °C
P
Û
MAX
[V]
EGATL
O
V
E
SL
U
P
–
SQUARE PULSE i [s]
t
WK/WR
Vishay Draloric Metal Oxide Resistors, High Power
www.vishay.com For technical questions, contact: ff1aresistors@vishay.com Document Number: 20128
160 Revision: 14-Sep-07
Note:
(1) Limiting for change of resistance at test
PERFORMANCE
TEST CONDITIONS OF TEST REQUIREMENTS (1)
Rated Dissipation at 70 °C
IEC 60115-1 4.25.1 1000 hours at 70 °C 1.5 hours “ON”, 0.5 hours “OFF” WK2 = ± 1.5 %
WK4/8 = ± 2.0 %
WR4/5 = ± 5.0 %
Endurance at UCT
IEC 60115-1 4.25.3 1000 hours at 155 °C without load ≤ ± 1 %
Overload Test
IEC 60115-1 4.13 Short time overload 5 seconds at 2.5 x rated voltage or ≤ ± twice the limiting
element voltage ≤ ± 0.25 %
Thermal Shock
IEC 60115-1 4.19, IEC 60068-2-14 Rapid change between upper and lower category temperature ≤ ± 0.25 %
Climatic Sequence
IEC 60115-1 4.23 Dry heat, damp heat cycle, cold, low air pressure ≤ ± 0.5 %
Damp Heat Steady State
IEC 60115-1 4.24, IEC 60068-2-3 56 days at 40 °C and 93 % relative humidity ≤ ± 1.5 %
Resistance to Soldering Heat
IEC 60115-1 4.18, IEC 60068-2-20 10 seconds at 260 °C solder bath temperature ≤ ± 0.25 %
Robustness of Terminations
IEC 60115-1 4.16 Tensile, bending and torsion ≤ ± 0.25 %
Vibration
IEC 60115-1 4.22 0.75 mm or 10 g, 10 Hz - 500 Hz 6 hours ≤ ± 0.25 %
APPLICABLE SPECIFICATIONS
• CECC 40000
• EN 140000 IEC 60115-1
Document Number: 91000 www.vishay.com
Revision: 18-Jul-08 1
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