Fusible Nickel

Film Resistors

FN Series

FN4

Power rating at 70°C

watts

0.4

Resistance range

ohms

0R1 to 20R

TCR

ppm/°C

See Figure 1

Resistance tolerance*

%

5, 10, 20

Standard values

E24 preferred

Thermal impedance

°C/watt

215

Ambient temperature range

°C

-55 to 155

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.

Telephone: +44 (0) 1670 822181 · Facsimile: +44 (0) 1670 829465 · Email: info@welwyn-tt.com · Website: www.welwyn-tt.com

* Below 1R, 10 and 20% only.

Electrical Data

Issue B · 03.02

A subsidiary of

TT electronics plc

Welwyn Components

168

Construction

The nickel 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 adjusted to the required value by a

helical cut; finally the flame retardant lacquer protection is

applied to the resistor body and the resistor is marked with an

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

Resistors are colour coded with five bands. Four of the bands

are used to indicate value and tolerance, with IEC 62 colours

being used. A fifth black band denotes constant current

fusibility.

Solvent Resistance

The body protection and marking are resistant to all normal

industrial cleaning solvents suitable for printed circuits.

Flammability

The resistors will not burn or emit encandescent particles

under any condition of applied temperature or power

overload.

Dimensions (mm) & Weight (g)

PCB

Min.

mounting

bend

Wt.

Type

L Max

D Max

f min

d nom

centres

radius

nom

FN4

6.2

2.5

21.0

0.6

10.2

0.6

0.3

Physical Data

L

D

f

d