Precision Metal
Film Resistors
RCP series
Welwyn Components
Precision resistors with
uprated power
Low TCRs over a wide resistance range
Tolerance down to 0.05%
Low noise and negligible voltage coefficient
Express delivery available
Electrical Data
RC55P
Power rating at 70°C
Resistance range
Limiting element voltage
Isolation voltage
TCR (20 to +70°C) & codes
Resistance tolerance (code)
Standard values
Thermal impedance
Ambient temperature range
°C/watt
°C
110
watts
ohms
volts
volts
ppm/°C
%
0.5
5R to 2M
350
500
RC65P
1.0
5R to 2M
500
500
0.05(W), 0.1(B), 0.25(C)
E24, E96 preferred
70
-55 to +155
60
RC70P
1.5
10R to 5M
500
700
See resistance
restrictions
Any value to order
Notes
5(V), 10(T), 15(Y), & 25(D)
Physical Data
Dimensions (mm) and Weight (g)
PCB
mounting
d nom. centres
0.6
0.6
0.8
10.2
12.7
18.4
Min
Bend
Radius
0.6
0.6
1.2
Wt.
nom.
0.24
0.40
1.15
Type
RC55P
RC65P
RC70P
L Max
7.2
10.0
15.5
D Max
2.5
3.7
5.5
f min
30
30
30
d
D
L
f
Construction
Ceramic rods are coated with a metal film and plated steel
caps are force fitted. A helical cut is used to adjust the film to
its final value.
Termination wires are welded to the caps and the resistor is
protected with a specially formulated epoxy coating.
Marking
Type reference, TCR code, resistance value and tolerance
code. The resistance value marking conforms to IEC 62.
Solvent Resistance
The body protection and marking are resistant to all normal
industrial cleaning fluids suitable for printed circuits.
Terminations
Material
Strength
Solderability
Solder-coated copper wire.
The terminations meet the requirements of
IEC 68.2.21
The terminations meet the requirements of
IEC 115-1, Clause 4.17.3.2
General Note
Welwyn Components reserves the right to make changes in product specification without notice or liability.
All information is subject to Welwyn’s own data and is considered accurate at time of going to print.
A subsidiary of
TT electronics plc
02 . 08
© 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
176
Precision Metal
Film Resistors
RCP series
Welwyn Components
Application Notes
Matched Sets and Networks
Welwyn has many years experience in the supply of matched
sets of precision resistors.
Resistors can be supplied matched for tolerance and TCR
down to ±0.02% and ±2ppm/°C, either as separate resistors
or pre-assembled and encapsulated within a plastic box.
The individual resistors within a set or module can be
manufactured with a tolerance of ±0.05% and a TCR of
±5ppm/°C.
Performance Data
RC55P Values 10
≤
100k
Actual Performance
Maximum
Load at rated power : 1000 hrs at 70°C
Dry heat : 1000 hrs at 155°C
Shelf life : 12 months at room temperature
Derating from rated power at 70°C
Short term overload
Climatic
Climatic category
Long term damp heat
Temperature rapid change
Resistance to solder heat
Vibration and bump
Noise (in a decade of frequency)
Voltage coefficient of resistance
∆R
%
∆R
%
∆R
%
∆R
%
µV/V
ppm/V
0.25
0.04
0.02
0.2
0.1
∆R
%
∆R
%
∆R
%
∆R
%
∆R
%
0.10
0.3
0.015
0.5
0.25
55/155/56
0.05
0.02
0.003
0.002
0.03
<1
0.5
0.2
0.06
0.06
1.0
Zero at 155°C
0.005
0.05
Typical
0.03
0.1
0.003
Other Values/Styles
*Actual Performance
Maximum
0.5
1.0
0.1
Zero at 155°C
0.1
0.3
55/155/56
0.1
0.05
0.03
0.02
0.1
<1
0.02
0.1
Typical
0.1
0.15
0.03
*An 0.01 ahm addition to be added to the performance claims of all resistors <10R.
Table of Resistance Restrictions
Tolerance
TCR
ppm/°C
5
10
15
25
RC55P
0.05%
10R to 500k
10R to 1M
10R to 1M
10R to 1M
.1-.25%
10R to 500k
10R to 1M
5R to 1M
5R to 2M
0.05%
10R to 500
10R to 1M
10R to 1M
10R to 1M
RC65P
.1-.25%
10R to 500
10R to 1M
5R to 1M
5R to 2M
0.05%
10R to 750k
10R to 1M
10R to 1M
10R to 1M
RC70P
.1-.25%
10R to 750k
10R to 1M
10R to 2M
10R to 5M
Packaging
The standard method of packaging RC55P resistors is taped in
ammopacks. Taped resistors on reel or loose packed
components can also be supplied by special request. The
standard packaging for RC65P and RC70P resistors is loose in
boxes. By special request the R65P components can also be
supplied taped on reel or in ammopack. In the case of tape
packed components the usable lead length is reduced by the
width of the tape.
© 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
02 . 08
Precision Metal
Film Resistors
RCP series
Welwyn Components
Ordering Procedure
Example: RC55P with TCR of 5ppm/°C at 31.6 kilohms and 0.1% tolerance in an ammo pack
box of up to 1000 pieces -
RC55PV
–
31K6B
I
Type
TCR
V
T
5 ppm/ °C
10 ppm/ °C
Y
D
15 ppm/ °C
25 ppm/ °C
Value (use IEC62 code)
Tolerance (use IEC62 code)
W
B
C
0.05%
0.1%
0.25%
Packing
I
Ammo
Bulk
RC55P, RC65P
RC70P
Up to 1000/box
250/box
Standard
© 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
02 . 08
