Metal Oxide Resistors, High Power
WK/WR
Vishay Draloric
www.vishay.com
For technical questions, contact: ff1aresistors@vishay.com
Document Number: 20128
146
Revision: 18-Jul-06
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
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.
Note
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 R
th
STANDARD ELECTRICAL SPECIFICATIONS
MODEL
SIZE
POWER RATING
P
70 C
W
LIMITING ELEMENT
VOLTAGE MAX.
V
TEMPERATURE
COEFFICIENT
ppm/K
TOLERANCE
%
RESISTANCE
RANGE
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)
V
eff
> 500
> 500
> 500
> 500
Thermal Resistance (max)
K/W
140
100
70
60
Insulation Resistance
> 10
9
Voltage Coefficient
1/V
< 10
-7
Thermal Time Constant
s
14
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
R
WK/WR
Metal Oxide Resistors, High Power
Vishay Draloric
Document Number: 20128
For technical questions, contact: ff1aresistors@vishay.com
www.vishay.com
Revision: 18-Jul-06
147
PART NUMBER AND PRODUCT DESCRIPTION WK2-SERIES
PART NUMBER: WK202070C1001FD5
MODEL/SIZE
SPECIAL CHARACTER
TCR
VALUE
TOLERANCE
PACKING
SPECIAL
WK20207
WK80922
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 = *10
0
1 = *10
1
2 = *10
2
3 = *10
3
4 = *10
4
5 = *10
5
6 = *10
6
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
PACKING
1)
WK2
50 ppm/K
100 ppm/K
200 ppm/K
49K9 = 49.9 k
50R1 = 50.1
1K0 = 1.0 k
1 %
2 %
5 %
A2
A5
R5
1) Please refer to table PACKING, page 148
PART NUMBER AND PRODUCT DESCRIPTION WK8-SERIES
PART NUMBER: WK80922001000J5C00
MODEL/SIZE
SPECIAL CHARACTER
TCR
VALUE
TOLERANCE
PACKING
SPECIAL
WK80922
0 = neutral
0 = standard
3 digit value
1 digit multiplier
MULTIPLIER
7 = *10
-3
8 = *10
-2
9 = *10
-1
0 = *10
0
1 = *10
1
2 = *10
2
3 = *10
3
4 = *10
4
5 = *10
5
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
PACKING
1)
WK8
100R = 100
47K = 47 k
2 %
5 %
AC
R1
1) Please refer to table PACKING, page 148.
0
2
1
0
1
F
D
0
K
2
5
W
7
0
0
C
0
9
1
0
0
J
5
0
K
8
C
W
2
0
2
0
WK/WR
Vishay Draloric
Metal Oxide Resistors, High Power
www.vishay.com
For technical questions, contact: ff1aresistors@vishay.com
Document Number: 20128
148
Revision: 18-Jul-06
Taping in acc. with IEC60286-1
D and L measured in acc. with IEC60294
d according to IEC60301
* 9 mm for WR5/WK8
PART NUMBER AND PRODUCT DESCRIPTION WR-SERIES
PART NUMBER: WR404140A1001GDE
MODEL/SIZE
SPECIAL CHARACTER
TCR
VALUE
TOLERANCE
PACKING
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 = *10
0
1 = *10
1
2 = *10
2
3 = *10
3
4 = *10
4
5 = *10
5
6 = *10
5
G = 2 %
J = 5 %
41 = A1 G73
51 = A1 G77
DE = RE G53
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
PACKING
1)
WR4
WR5
1K0 = 1.0 k
50R1 = 50.1
2 %
5 %
A1 (G73)
A1 (G77)
RE (G53)
RE (G73)
RP
1) Please refer to table PACKING, below.
PACKING
MODEL
REEL
BOX
PIECES/REEL
CODE
MIN. ORDER QTY
PACKING UNITS
PIECES/BOX
CODE
MIN. ORDER QTY
PACKING 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
DIMENSIONS
L
1
L
d
D
B
e
6 mm*
MODEL
DIMENSIONS [in millimeters]
D
L
L
1max
B
d
e
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
0
4
1
0
1
G
D
0
R
4
E
W
4
0
1
A
WK/WR
Metal Oxide Resistors, High Power
Vishay Draloric
Document Number: 20128
For technical questions, contact: ff1aresistors@vishay.com
www.vishay.com
Revision: 18-Jul-06
149
120
100
80
60
40
20
0
- 55
0
40
80
120
160 200
240
280 320 360
70 AMBIENT TEMPERATURE IN C
DERATING
%
N
I
R
E
W
O
P
D
E
T
A
R
300
250
200
150
100
50
0
0
1.0
2.0
3.0
4.0
5.0
POWER IN W
TEMPERATURE RISE
C
N
I
E
S
I
R
E
R
U
T
A
R
E
P
M
E
T
WR4
WK2
WK2
WR4
WR5
WK8
WR5
WK8
1000
100
10
1
0.1
WR 5
WR 4
a) P
b)
u 70 C
c)
max
see diagram below
d) ~ 10R
Secondary conditions:
WK 8
]
W
[
P
G
N
I
T
A
R
R
E
W
O
P
WK 2
SQUARE PULSE ti [S]
PULSE RATING P 0
SQUARE PULSE ti [S]
10
WR 5
WR 4
a) P
P
70
permissible constant power at
u = 70 C
b)
u 70 C
c)
max
see diagram below
d) ~ 10R
Secondary conditions:
WK 8
]
W
[
P
G
N
I
T
A
R
R
E
W
O
P
WK 2
PULSE RATING P
P70
10
-5
10
-4
10
0
10
-1
10
0
10
10
1
10
-1
10
-2
10
0
10
-3
10
2
10
-1
10
-5
10
-4
10
-3
10
-2
10
3
NON-LINEARITY
]
B
d
[
3
A
Y
T
I
R
A
E
N
I
L
-
N
O
N
130
120
110
100
90
1K
10K
100K
1M
10M
RESISTANCE VALUE IN
WR4
WR5/WK8
CURRENT NOISE
10
1
0.1
0.01
E
S
I
O
N
T
N
E
R
R
U
C
V
/
V
WR4
10K
100K
1M
10M
RESISTANCE VALUE IN
2000
1000
0
WR 5/WK8
a) P
max.
see Diagrams above
b) See diagrams above
c)
u 70 C
Secondary conditions:
WR 4
]
V
[
X
A
M
E
G
A
T
L
O
V
E
S
L
U
P
MAX. PULSE VOLTAGE
SQUARE PULSE ti [S]
WK 2
10
-5
10
-4
10
-2
10
-3
10
-1
10
10
0
WR5/WK8
WK/WR
Vishay Draloric
Metal Oxide Resistors, High Power
www.vishay.com
For technical questions, contact: ff1aresistors@vishay.com
Document Number: 20128
150
Revision: 18-Jul-06
* Limiting for change of resistance at test
PERFORMANCE
TEST
CONDITIONS OF TEST
REQUIREMENTS*
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
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