Resistors
Compact Flameproof Power
Compact Flameproof Power
Wirewound Resistors
Wirewound Resistors
WP-S Series
Small size
WP-S Series
for power rating
Enhanced pulse handling capability
Small size for power rating
Flameproof protection
Enhanced pulse handling capability
Flameproof protection
SMD Z-form available
Surface mount ZI-form option
RoHS compliant with Pb-free terminations
RoHS compliant with Pb-free terminations
Welwyn Components
All Pb-free parts comply with EU Directive 2011/65/EU amended by (EU) 2015/863 (RoHS3)
Electrical Data
WP1S
Power rating at 25 °C
5s overload rating at 25ºC
Short pulse performance
Resistance range
Limiting element voltage
TCR
Isolation Voltage
Resistance Tolerance
Standard Values
Thermal Impedance
Ambient temperature range
°C/wat t
°C
140
110
ohms
volts
ppm/° C
v olts
%
250
<20R: 5
≥20R:
1, 2, 5
E24 preferred
90
-55 to +200
82
62
54
R068 to 430R
50
watt s
watts
1
5
WP2S
WP2S / WPP2R
2
10
R05 to 900R
50
<1R: 350
WP25S
2.5
12.5
WP3S
3
15
WP4S
4
20
R01 to 10K
100
500
<R10: 5
<20R: 5
≥R10:
1, 2, 5
≥20R:
1, 2, 5
WP5S
5
25
R015 to 6K8
150
See Pulse Performance graphs
R05 to 900R R01 to 2K2
75
100
≥1R:
200
350
Physical Data
Dimensions (mm) & Weight (g)
Type
L max
D max
f min
d nom
PCB
mount
centres
10.20
12.50
17.50
0.8
20.00
19.00
22.00
1.2
Min
bend
radius
0.6
Wt.
nom
0.22
0.50
0.50
1.10
1.00
1.75
D
WP1S
WP2S
WP25S
WP3S
WP4S
WP5S
6.2
9.0
12.5
14.5
13
16.5
2.8
3.6
4.5
5.2
(Note 1)
5.6
7.0
(Note 2)
(Note 3)
21.20
19.80
17.80
24.55
22.75
23.55
0.6
d
L
f
Note 1: 5.4 for values
≥
0R1 Note 2: 5.8 for values
≥
0R1 Note 3: 7.2 for values
≥
0R1
Construction
A high purity ceramic substrate is assembled with interference fit end caps to which are welded the terminations. The resistive
element is wound on the substrate and welded to the caps. Flameproof silicone cement coating is applied prior to marking with
indelible ink. The components are then leadformed if required and packed.
General
Note
General
Note
Welwyn Components
the right to make changes in product specification
specification without notice or liability.
TT Electronics reserves
reserves the right to make changes in product
without notice or liability.
All information is subject to Welwyn’s own data and is considered accurate at time of going to print.
All information is subject to TT Electronics’ own data and is considered accurate at time of going to print.
BI Technologies IRC Welwyn
A subsidiary of
www.ttelectronics.com/resistors
TT electronics plc
08.10
11.20
©
TT Electronics plc
©
Welwyn Components Limited
· Bedlington, Northumberland NE22 7AA, UK
Telephone: +44 (0) 1670 822181 · Facsimile: +44 (0) 1670 829465 · Email: info@welwyn-tt.com · Website: www.welwyn-tt.com
Resistors
Compact Flameproof Power
Compact Flameproof Power Wirewound Resistors
Wirewound
Flameproof Power
Compact
Resistors
WP-S
Series
WP-S
Series
WP-S Series
Wirewound
WP-S Series
Resistors
Welwyn Components
Welwyn Components
Terminations
Material:
Material:
Strength:
Strength:
Material:
Solderability:
Solderability:
Terminations
Strength:
Solderability:
Hot tin dipped copper wire
Hot tin dipped copper wire
The terminations meet the requirements of IEC 68.2.21
The terminations meet the requirements of IEC 68.2.21
Hot tin dipped
The terminations
copper wire
The terminations meet the requirements of IEC 115-1 Clause 4.17.3.2
meet the requirements of IEC 115-1 Clause 4.17.3.2
Marking
The terminations meet the requirements of IEC 68.2.21
The terminations meet the requirements of IEC 115-1 Clause 4.17.3.2
WP1S, WP2S, WPP2R, WP25S and WP3S resistors R10 and above are marked with four or five colour bands in conformance.
WP1S, WP2S, WPP2R, WP25S and WP3S resistors R10 and above are marked with four or five colour bands in conformance.
with IEC62. below R10 are marked with three bands (two digits indicating value
with
milliohms, and tolerance); there is no multiplier
with IEC62. below R10 are marked with three bands (two digits indicating value in milliohms, and tolerance); there is no multiplier
WP1S, WP2S, WPP2R, WP25S and WP3S resistors R10 and above are marked
in
four or five colour bands in conformance.
band. WP4S and WP5S resistors are legend
three bands (two digits indicating value
value and tolerance.
band. WP4S and WP5S resistors are legend marked with type reference, resistance
in milliohms, and tolerance); there is no multiplier
with IEC62. below R10 are marked with
marked with type reference, resistance value and tolerance.
Marking
Solvent Resistance
Flammability
Flammability
band. WP4S and WP5S resistors are legend marked with type reference, resistance value and tolerance.
The body protection and marking are resistant to all normal industrial cleaning solvents suitable for printed circuits.
The body protection and marking are resistant to all normal industrial cleaning solvents suitable for printed circuits.
The body protection and marking are resistant to all normal industrial cleaning solvents suitable for printed circuits.
Solvent Resistance
The resistor coating will not burn or emit incandescent particles under any condition of applied temperature or power overload.
The resistor coating will not burn or emit incandescent particles under any condition of applied temperature or power overload.
The resistor coating will not burn or emit incandescent particles under any condition of applied temperature or power overload.
Performance Data
Performance Data
Maximum
Maximum
Load at rated power: 1000hrs @ 25°C
Load at
at rated power: 1000hrs @ 25°C
Load
rated power: 1000hrs @ 25°C
Dry heat: 1000hrs @
@ 200°C
Dry heat: 1000hrs @ 200°C
Dry heat: 1000hrs
200°C
Short term overload (5
(5
Pr
Pr for 5s)
Short term overload (5 x Pr for 5s)
Short term overload
x
x
for 5s)
Derratti
at
g
n
ffrrom
m
atted
e
po
po
err
e
@25
2
C
°C
De
er
in g
g
o
ro
rra
rat d
ow e @ 25°
5
ed p w
w r @
°C
D
a n
i
f
m
Climatic
Climatic
Climatic
Climatic category
Climatic category
Climatic category
TRC
Vibration
TRC &
& Vibration
TRC & Vibration
Robustness
solder heat
Robustness &
& solder heat
Robustness & solder heat
Long term damp heat (56 days)
Long term damp heat (56 days)
Long term damp heat (56 days)
∆
R%
∆
R%
∆
R%
∆
R%
∆
R%
∆
R%
∆
R%
∆
R%
∆
R%
∆
R%
∆
R%
∆
R%
∆
R%
∆
R%
∆
R%
∆
R%
∆
R%
∆
R%
∆
R%
∆
R%
∆
R%
5 +0.001Ω
5
5 +0.001Ω
+0.001Ω
5 +0.001Ω
5
5 +0.001Ω
+0.001Ω
5 +0.001Ω
5
5 +0.001Ω
+0.001Ω
Maximum
Typical Change
Typical Change
3
3
3
3
3
3
1
1
1
Ze
Z
o
r
att
a
28
28
C
°C
Zerr
e o
2 80°
0
o a
t
0°C
2
2
2
55/200/56
55/200/56
55/200/56
1
1
1
1
1
1
1
1
1
Typical Change
5 +0.001Ω
5
5 +0.001Ω
+0.001Ω
5 +0.001Ω
5
5 +0.001Ω
+0.001Ω
5 +0.001Ω
5
5 +0.001Ω
+0.001Ω
5 +0.001Ω
5
5 +0.001Ω
+0.001Ω
Pulse Performance
Pulse Performance
The pulse energy capacity limits in the graph below relate to pulses below 100ms duration, low mean power dissipation and at
The pulse energy capacity limits in the graph below relate to pulses below 100ms duration, low mean power dissipation and at
25ºC.
25ºC.
25ºC.
The pulse energy capacity limits in the graph below relate to pulses below 100ms duration, low mean power dissipation and at
WP-S Short Pulse Energy Capacity
WP-S Short Pulse Energy Capacity
100
100
100
WP-S Short Pulse Energy Capacity
Energy (joules)
Energy (joules)
10
10
10
WP5S
1
WP5S
WP5S
WP25S
WP1S
WP2S // WPP2R
WP2S WPP2R
WP4S
1
1
0.1
1
10
100
WP4S
WP4S
WP3S
WP3S
WP2S / WPP2R
WP25S WP3S
WP25S
WP2S / WPP2R
WP1S
WP1S
0.1
0.1
0.1
0.1
0.1
© Welwyn Components Limited
1000
10000
TT Electronics reserves the right to make changes in product specification without notice or liability.
© Welwyn Components Limited
Bedlington, Northumberland NE22 7AA, UK
© Welwyn Components Limited
Bedlington, Northumberland NE22 7AA, UK
All information subject
data and is considered accurate at time of going to print.
Telephone: +44
is
(0) 1670
to TT Electronics’ own
+44 (0) 1670 829465 ·· Email: info@welwyn-tt.com ·· Website: www.welwyn-tt.com
Telephone: +44 (0) 1670 822181 ·· Facsimile: +44 (0) 1670 829465 Email: info@welwyn-tt.com Website: www.welwyn-tt.com
822181 Facsimile:
General Note
(0) 1670 822181 · Facsimile: +44 (0) 1670 829465 · Email: info@welwyn-tt.com · Website: www.welwyn-tt.com
Telephone: +44
BI Technologies
10
Value (ohms)
100
10
100
Value (ohms)
Bedlington, Northumberland NE22
Value (ohms)
7AA, UK
1
1
1000
1000
10000
10000
08.10
IRC Welwyn
08.10
08.10
www.ttelectronics.com/resistors
© TT Electronics plc
11.20
Compact Flameproof Power Wirewound Resistors
Wirewound Resistors
WP-S Series
WP-S Series
Resistors
Flameproof Power
Compact
Welwyn Components
Application Notes
1. If the resistors are to dissipate full rated power, it is recommended that the terminations should not be soldered closer than
4mm from the body.
2. Due to operating temperature limits imposed by some PCB materials, derating may be necessary. An estimate of the
temperature rise to be expected at the center of the body can be calculated using the thermal impedance figures given under
Electrical Data.
3. WP-S resistors can also be supplied with radial, goalpost or lancet pre-formed leads - see
3. WP-S resistors can also be supplied with radial, goalpost or lancet pre-formed leads. WP2S, WP3S, WP4S and WP5S are also
https://www.ttelectronics.com/TTElectronics/media/ProductFiles/Resistors/ApplicationNotes/TN008-resistors-Leadform-Capability.pdf.
available in an SMD format with ZI formed leads and packed in blister tape.
WP2S, WP3S, WP4S and WP5S are also available in an SMD format with ZI formed leads and packed in blister tape - see
For details see https://www.ttelectronics.com/TTElectronics/media/ProductFiles/Resistors/Datasheets/ZI-form.pdf.
https://www.ttelectronics.com/TTElectronics/media/ProductFiles/Resistors/Datasheets/ZI-form.pdf.
Radial
Hairpin
Goalpost
Goalpost
Lancet
Lancet
Z-f
ZI-form
orm
Also a 2W and 3W radial taped version is available as shown below
Radial Taped Dimensions (mm)
Packaging
The standard packaging for
L
WP-S is taped. The critical dimensions are shown in Figure 1. The component wires will not
Component body length
10.0 Max
14.5 Max
protrude beyond the outside edge of the tapes. Taped product is then packed into boxes or onto reels; see Ordering Procedure
Component body diameter
D
4.0 Max
5.2 Max
for details. Alternative packaging is available by request. Pre-formed resistors are supplied loose packed in plastic bags or boxes.
Terminal lead diameter
d
0.8 Nom
Component pitch
Hole pitch
P
Po
P1
P2
F
12.7±0.5
12.7±0.2
3.85±0.3
5.85±0.5
+0.75 -0.34
5
18.0±0.3
9.0±0.25
12.7±1.0
12.7±0.3
3.85±0.7
6.35±1.3
5.0±1.0
18.0±1.0
9.0±0.5
17.0±1.0
23.0 Max
Dimension
Notation
WPP2R*
WP3SR
Dimensions (mm)
Component to hole offset
Lead pitch
Width of backing strip
Position of hole
b
c
Figure 1
WP1S
WP2S
52
52
52
5
5.0
5
WP25S
W
W1
C
WP3S
Diameter of hole
Height to lead form
WP4S
Height from lead form
Height to resistor
Width of adhesive tape
Length of protrusion
67
Do
63
Ho
63
Ho1
Ho2
W0
l
K1
K2
10
4.0±0.3
16.0±0.3
10
WP5S
10
17.0 Max
f1
6
b
f2
6
18.0 Min
15.0±0.5
<2.5
2.0±0.3
3.0±0.5
1.5±0.25
1.0±0.2
--
2.0 Min
Body location f1 - f2 < 1.4mm
Form dimensions
K3
K4
K5
*Although body dimensions differ slightly, WPP2R Performance and Electrical Data are identical to those of WP2S
General Note
TT Electronics reserves the right to make changes in product specification without notice or liability.
All information is subject to TT Electronics’ own data and is considered accurate at time of going to print.
© Welwyn Components Limited
Bedlington, Northumberland NE22 7AA, UK
Telephone: +44 (0) 1670 822181 · Facsimile: +44 (0) 1670 829465 · Email: info@welwyn-tt.com · Website: www.welwyn-tt.com
BI Technologies IRC Welwyn
www.ttelectronics.com/resistors
08.10
© TT Electronics plc
11.20
Compact Flameproof Power Wirewound Resistors
WP-S Series
Resistors
Packaging
The standard packaging for WP-S is taped. The critical dimensions are shown in Figure 1. The component wires will not
protrude beyond the outside edge of the tapes. Taped product is then packed into boxes or onto reels; see Ordering Procedure
for details. Alternative packaging is available by request. Pre-formed resistors are supplied loose packed in plastic bags or boxes.
Dimensions (mm)
WP1S
WP2S
WP25S
WP3S
b
52
52
52
67
c
5
5
5
10
Figure 1
C
WP4S
63
10
Compact Flameproof Power
WP5S
63
10
Wirewound Resistors
f1
6
b
f2
6
WP-S Series
Body location f1 -
Welwyn Components
f2 < 1.4mm
EMC REPLACEMENT
Example: EMC2-33RMI
(EMC2, 33 ohms
in ammo pack box of 2500 pieces -
Example: WP2S at 680 ohms and 5% tolerance
±20%, Pb-free)
Example: WP2S-680RJA25
(WP2S, 680 ohms ±5%, Pb-free)
1
1
Value (use IEC 62 code)
Type
E
M
W
C
P
2
2
-
3
S
WP2S
-
2
3 R
6
–
8
3
M I
0
680R
J
R
4
5
2
3
A
J
2
4
5
A25
Ordering Procedure
Ordering Procedure
WP-S ADDITIONAL
A5
WP1S
5000/box
1500/box
A15
A1
A1
Ammo
WP25S
1
2
3
4
5
IEC
Tolerance (use
1
62 code)
2
3
4
Type
Leadforming
Value
Tolerance
Packing
Type
Value
Tolerance
Termination & Packing
F
EMC2
1%
Blank = Axial
Bedlington, Northumberland NE22 7AA, UK
I
3/4 characters K = ±10%
EMC2 Ammo 2000/box
© Welwyn Components Limited
WP1S Radial characters
1670
= ±1%
Email:
= ±20% WP1S
·
EMC2R Reel 1500/reel
3/4
Facsimile: +44 (0)
=F
829465 ·
MA5
5000/box
R=
R ohms
T15
Telephone: +44 (0) 1670 822181 ·
taped
info@welwyn-tt.com Website: www.welwyn-tt.com
G
2%
WP2S
R = ohms
G = ±2% A25
WP2S
2500/box
Ammo pack
Pb-free
J
5%
WP25S
K = kilohms
J = ±5% A15
WP25S
1500/box
(RoHS)
WP3S
A1 WP3S, WP4S
1000/box
WP4S
T075
WP5S
Tape & reel 750/reel
Packing
WP5S
PB
All sizes
SnPb finish Packing as for Pb-free
08.10
A25
WP2S
2500/box
Example: WPP2R-680RJT15
(WPP2R radially formed & taped, 680 ohms ±5%, Pb-free)
W
P
P
1
Tape
2
WP3S
WP4S
R
-
6
1000/box
0
8
3
750/reel
3
Value
3/4 characters
R = ohms
K = kilohms
1000/box
Standard
R
J
4
4
T
1
5
5
T075
2
WP5S
2
1
Type
WP3S
5
Packing
T15
A2
T1
WPP2R Tape & reel 1500/reel
Ammo pack 2000/box
WP3SR Tape & reel
1000/reel
Leadforming
Tolerance
F = ±1%
G = ±2%
J = ±5%
WPP2 R = Radial taped
General Note
TT Electronics reserves the right to make changes in product specification without notice or liability.
All information is subject to TT Electronics’ own data and is considered accurate at time of going to print.
BI Technologies IRC Welwyn
www.ttelectronics.com/resistors
© TT Electronics plc
11.20
