General Note
IRC reserves the right to make changes in product specification without notice or liability.
All information is subject to IRC’s own data and is considered accurate at time of going to print. A subsidiary of
TT electronics plc
• 4222 South Staples Street • Corpus Christi Texas 78411 USA
Wire and Film Technologies Division
Telephone: 361 992 7900 • Facsimile: 361 992 3377 • Website: www.irctt.com
Legend mark or color code
depending on size
Solder coated
copper wire
Flameproof protection
Power Metal Film
Resistor
MF-S Series
• Flameproof protection
• Small size for power rating
• Range of 4 sizes: 0.5 watt to 3 watt at 70°C
Electrical Data
IRC
Type
Power
Rating
@ 70°C
(watts)
Resistance
Range
(ohms)
Limiting
Element
Voltage
(volts)
TCR
(ppm/°C)
Isolation
Voltage
(volts)
Resistance
Tolerance
(%)
Standard
Values
Thermal
Impedance
(°C/watt)
Operating
Temperature
Range
(°C)
MF1/2S 0.5
0.1 - 1M
350
150
500 ≤1Ω: 5, 10
>1Ω: 1, 2, 5
E24
Preferred
140
-55 to 235
MF1S 1.0 110
MF2S 2.0
0.1 - 470K <1Ω: 350
≥10Ω: 150
80
MF3S 3.0 700 60
Characteristic Maximum
Loaded at Rated Power: 1000 hrs at 70°C 5
Shelf Life: 12 months at room temperature 1
Derating from Rated Power at 70°C zero at 155°C
Climatic 1
Climatic Category 40/125/56
Temperature Rapid Change 0..5
Resistance to Solder heat 0.5
Environmental Data
MF-S Series Issue October 2008 Sheet 1 of 3
• 4222 South Staples Street • Corpus Christi Texas 78411 USA
Wire and Film Technologies Division
Telephone: 361 992 7900 • Facsimile: 361 992 3377 • Website: www.irctt.com
Physical Data
Power Metal Film
Resistor
Lf
D
d
Dimensions (Inches and (mm)) & Weight (g)
IRC
Type L max D max f min d nom
PCB
Mounting
Centers
Min Bend
Radius Wt. nom
MF1/2S 0.244
(6.2)
0.090
(2.3)
0.039
(21.0)
0.024
(0.6)
0.402
(10.2)
0.024
(0.6) 0.3
MF1S 0.354
(9.0)
0.134
(3.4)
0.772
(19.6)
0.031
(0.8)
0.500
(12.7)
0.047
(1.2) 0.5
MF2S 0.492
(12.5)
0.165
(4.2)
0.700
(17.8)
0.031
(0.8)
0.724
(18.4)
0.047
(1.2) 0.9
MF3S 0.571
(14.5)
0.201
(5.1)
0.937
(23.8)
0.031
(0.8)
0.799
(20.3)
0.047
(1.2) 1.1
Construction
The resistance element is a precisely controlled thin film
of metal alloy on a high purity ceramic core, protected
by a cement coating applied so that terminations remain
completely clear.
This permits a well defined body length, (clean lead to
clean lead dimension L).
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
MF Series resistors are color coded with 4 bands. IEC 62
colors are used.
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 incandescant particles under
any condition of applied temperature or power overload.
MF-S Series Issue October 2008 Sheet 2 of 3
• 4222 South Staples Street • Corpus Christi Texas 78411 USA
Wire and Film Technologies Division
Telephone: 361 992 7900 • Facsimile: 361 992 3377 • Website: www.irctt.com
Power Metal Film
Resistor
Application Notes
1. If the resistors are to dissipate full rate power, it
is recommended that the terminations should not be
soldered closer than 4mm from the body.
2. Due to operating temperature limitations imposed
by some pcb materials, derating may be necessary. An
estimate of the temperature rise to be expected can be
calculated using the thermal impedance figures given
under Electrical Data.
3. Lead formed resistors can also be supplied. Standard
options of Lancet, Radial, and Goalpost forming are
shown in lead Form Information section.
Type b c
MF1/2S 52 5
MF1S 52 5
MF2S 52 5
MF3S 67 10
Packaging
The preferred method of packaging is taped and ammo packed.
See figure 1 for critical dimensions.
Alternative packaging is available by special request.
Type Code MF1/2S MF1S MF2S MF3S
MF1/2S R 5000 2500 2500 1000
MF1S A 5000 2500 2500 N/A
MF2S A 2000 1000 1000 N/A
Sample Part No.
IRC Type
MF1/2S, MF1S, MF2S, MF3S
Value
(Use IEC 62 code)
Tolerance
(Use IEC 62 code)
J = 5%, K = 10%
Packaging Details
R = Reel, A = Ammo
Ordering Data
MF2S 6802 J R
MF-S Series Issue October 2008 Sheet 2 of 3
b
f1
c
66
f2
Body location: f1 - f2 ≤ 1.4mm