2500 Datasheet, PDF (1/1 Pages) Welwyn Components Limited – Low Value Metal Film Resistors

Low Value
Metal Film Resistors
2500 Series
• ^{Resistance values down to 0.025 ohms}
• ^{Low inductance}
• ^{Tolerances down to 1%}
• ^{Flameproof protection}
Welwyn Components
Electrical Data
Power rating at 25°C
Power rating at 70°C
Resistance range
Isolation voltage
TCR (+20° to 70°C)
Resistance tolerance
Thermal impedance
Values
Operating temperature range
watts
watts
ohms
volts
ppm/°C
%
°C/watt
°C
2504
2.0
1.5
0R025 to 1
700
See Figure 1
1, 2, 5, 10
65
E24
-55 to +150
Notes
Measured at 6mm from caps
Physical Data
Dimensions (mm) & weight (g)
PCB
Min.
mounting bend Wt.
Type
L Max D Max f min d nom centres radius nom
2504
14.5
5.3
23.8
0.8
20.3
1.2
1.1
dD
L
f
Construction
The metal film is deposited on a high purity ceramic rod. End
caps are force fitted and termination wires welded to the
caps. The resistive film is then adjusted to the required value;
finally the cement protection is applied to the resistor body
and marked with indelible ink.
Terminations
Material
Solder-coated copper wire.
Strength
The terminations meet the requirements of
IEC 68.2.21
Solderability The terminations meet the requirements of
IEC 115-1, Clause 4.17.3.2
Marking
Values below R10 are colour coded with 3 bands. Values R10
and above are marked with 4 bands. IEC 62 colours are used.
Solvent Resistance
The body protection and marking are resistant to all normal
industrial cleaning fluids suitable for printed circuits.
Flammability
The resistors will not burn or emit incandescent particles
under any condition of applied temperature or power
overload.
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.
© Welwyn Components Limited · Bedlington, Northumberland NE22 7AA, UK
Telephone: [phone] · Facsimile: [phone] · Email: [e-mail] · Website: www.welwyn-tt.com
A subsidiary of
TT electronics plc
Issue B · 03.02
155