How do you identify a fusible resistor? (wg. Watts Electronics) In WWF (wire wound fusible) series, resistors up to 5W, the resistance value is colour coded with 3 bands plus a tolerance band. An additional white band indicates that the resistor is fusible. For resistors 6W and above, the value is printed on the resistor. Jak rozpoznać rezystor bezpiecznikowy? W serii WWF, rezystory do 5W, wartość rezystancji jest kodowana kolorami za pomocą 3 pasków plus pasek tolerancji. Dodatkowy biały pasek oznacza, że rezystor jest bezpiecznikowy. Dla rezystorów 6W i wyższych wartość jest wydrukowana na rezystorze. https://obrazki.elektroda.pl/6397189300_1637578344_thumb.jpg Link Inne firmy też znakują białym paskiem np. PPC, choć to tylko jedno z rozwiązań: 1115199 Ponieważ, przy oznaczaniu tolerancji (ostatni pasek) przy 5 paskowym kodowaniu nie występuje biały, więc część producentów wybrała ten kolor do oznaczania fusible fixed resistor. Myślę, że gdyby się wszyscy tak umówili, to sprawa byłaby od dawna oczywista i łatwa do identyfikacji. Biały pasek na końcu powinien zagościć na stałe jako znamię identyfikujące rezystory bezpiecznikowe. Jeszcze jakiś tekst: 1115208 Training: Link
Phoenix Passive Components
FUSIBLE RESISTOR - NFR25H
FEATURES
• Metal film technology
• Suitable for protection of circuit boards and designs
• Overload protection without risk of fire
• Defined interruption behavior (fusing time)
• Wide range of overload currents
• Flame retardant lacquer
• High stability, reliability and uniformity
characteristics
• Various forming styles available
• Various packing and taping configurations
•
MARKET SEGMENTS AND APPLICATIONS
INDUSTRY SECTOR
APPLICATION SEGMENT
END-USER EQUIPMENT
Controls
Power supplies
Power system control
Central heating controls
Telecom
Data Communication
Line protection resistor
Power supplies
Modems
Consumer
Sound & Vision
Amplifiers
TV
VCR
Industrial
NFR25H
PHOENIX DO BRASIL LTDA
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Phoenix Passive Components
TECHNOLOGY
A homogeneous film of metal alloy is deposited on a high-grade ceramic body. After a helical groove has
been cut in the resistive layer, tinned connecting wires of electrolytic copper are welded to the end-caps. The
resistors are coated with a gray flame retardant lacquer, which provides electrical, mechanical and climatic
protection. The encapsulation is resistant to all cleaning solvents in accordance with MIL-STD-202, method
215 and IEC 60068-2-45.
QUICK REFERENCE DATA
NFR25H ± 5%
(E24 series)
DESCRIPTION
Cu-lead
0.22 Ω - 15 KΩ
Resistance range
Maximum dissipation at Tamb = 70 °C
0.5 W
Thermal resistance (Rth)
150 K/W
Limiting voltage (DC or RMS)
350 V
Rated voltage (1)
Pn x R
Temperature coefficient:
0.22 Ω ≤ R ≤ 4.7 Ω
4.7 Ω & lt; R ≤ 15 kΩ
±200ppm/°C
±100ppm/°C
Climatic category (IEC 60068)
55/155/56
Basic specifications
IEC 60115 - 1 and 60115 - 2
Stability ∆R/Rmax after:
Load
±1% + 0.05 Ω
Climatic tests
±1% + 0.05 Ω
±0.25% + 0.05 Ω
Resistance to soldering heat
(1) Maximum rated voltage is the limiting voltage
NFR25H
PHOENIX DO BRASIL LTDA
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Phoenix Passive Components
MECHANICAL DATA
AXIAL STYLE
Fig. 1
Table 1. Mechanical data.
PRODUCT
A
L1
max
L2
max
∅D
max
B1 - B2max
∅d
S
WEIGHT
gr/100 pcs
NFR25H
52.0 + 1.5 / - 0.0
(2.05 + 0.06 / - 0.00)
6.5
(0.26)
7.5
(0.30)
2.5
(0.10)
1.2
(0.05)
0.58 ±0.05
(0.023 ±0.002)
5.0 ±0.1
(0.20 ±0.01)
22.0
Dimensions unless specified in mm (inches)
MOUNTING
The resistors are suitable for processing on automatic insertion equipment, cutting and bending machines. A
radial taped version economizes space on the PCB. The double kink style offers great advantages for
manual insertion improving the mounting stability for the customer. They have a real snap in function to fix
the resistor in PCB without weakening the connecting leads.
NFR25H
PHOENIX DO BRASIL LTDA
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Phoenix Passive Components
ELECTRICAL CHARACTERISTICS
DERATING
The power that the resistor can dissipate depends on the operating temperature.
Fig. 2. Maximum dissipation (Pmax) in percentage of rated power as a function of ambient temperature (Tamb)
APPLICATION INFORMATION
Hot spot
Solder spot
Fig. 3. Hot spot temperature rise (∆T) as a
function of dissipated power.
Fig. 4. Temperature rise (∆T) at the lead (solder
spot) as a function of dissipated power at various
lead lengths after mounting
Note: The maximum permissible hot spot temperature is 155 °C
NFR25H
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Phoenix Passive Components
FUSING CHARACTERISTIC
The resistors will fuse without the risk of fire and within an indicated range of overload. Fusing means that
resistive value of the resistor increases at least 100 times; see Figs. 5 and 6.
The fusing characteristic is measured under constant voltage.
This graph is based on measured data witch may deviate according to the application.
Fig. 5. Fusing characteristic: ≤ 1 Ω
Fig. 6. Fusing characteristic: & gt; 1 Ω
PULSE LOADING CAPABILITIES
Fig. 7. Pulse on a regular basis, maximum permissible peak pulse power (^Pmax) as a function of pulse duration (ti)
NFR25H
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Phoenix Passive Components
Fig. 8. Pulse on a regular basis, maximum permissible peak pulse voltage (^Vmax) as a function of pulse duration (ti)
MARKING
The nominal resistance and tolerance are marked on the resistor using four colored bands in accordance
with IEC publication 60062 “color code for fixed resistors”. There is a fifth white band in order to indicate the
type of resistor. Standard values of nominal resistance are taken from the E24 series for resistors with a
tolerance of ±5%. The values of the E24 series are in accordance with IEC publication 60063.
ORDERING INFORMATION
Table 2. Ordering code.
QUANTI TY
(pcs)
0.58 Cu
(0.023)
TOLERANCE
±5%
TAPING
52.0
(2.05)
PACKAGING
ORDERING
CODE
AMMOPACK
LEAD ∅
2322 207 33xxx
REEL
2322 207 23xxx
AMMOPACK
2322 207 13xxx
5000
1000
Dimensions unless specified in mm (inches)
Check ”Formed leads” specifications to see related part-numbers
NFR25H
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Phoenix Passive Components
The resistors have a 12 digit ordering code starting with 2306 or 2322.
The next 5 digits indicate the resistor type and packaging, see table 2.
The last 3 digits indicate the resistance value:
- The first 2 digits of these last 3 indicate the actual resistance value;
- The last digit indicates the resistance decade in accordance with table 3.
Table 3. Last digit of ordering code.
RESISTANCE DECADE
LAST DIGIT
0.22 Ω - 0.91 Ω
7
1 Ω - 9.1 Ω
8
10 Ω - 91 Ω
9
100 Ω - 910 Ω
1
1 kΩ - 9.1 kΩ
2
10 kΩ - 15 kΩ
3
Example:
NFR25H, 750 Ω, ±5%, ammopack 1000 pcs is 2322 207 13751.
NAFTA ORDERING INFORMATION
Table 4. NAFTA ordering code.
± 5%
QUANTITY
(pcs)
PACKAGING
1000
AMMOPACK
52.0
(2.047)
5000
52.0
(2.047)
0.58 Cu
(0.023)
TOLERANCE
TAPING
52.0
(2.047)
LEAD ∅
5000
NAFTA
ORDERING CODE
5065FMxxxxxJ08AFX (1)
5065FDxxxxxJ08AFX (2)
REEL
5065FMxxxxxJ12AFX (1)
5065FDxxxxxJ12AFX (2)
AMMOPACK
5065FMxxxxxJ18AFX (1)
5065FDxxxxxJ18AFX (2)
Dimensions unless specified in mm (inches)
(1) Part number for values ≤ 15 Ω
(2) Part number for values & gt; 15 Ω
The ohmic value in the NAFTA ordering code (see table 4) is represented by the “xxxxx” in the middle of the
above ordering code. Table 5 gives some examples how to use these 5 digits.
NFR25H
PHOENIX DO BRASIL LTDA
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Phoenix Passive Components
Table 5. Ohmic value examples.
VALUE
5 DIGITS
1Ω
1R000
10 Ω
10R00
100 Ω
100R0
1 kΩ
1K000
10 kΩ
10K00
100 kΩ
100K0
1 MΩ
1M000
PACKAGING
TAPE IN AMMOPACK
Table 6. Ammopack.
NFR25H
TAPING
M
N
P
QTUANTIY
(pcs)
52.0 + 1.5 / - 0.0
(2.05 + 0.06 / - 0.00)
82
(3.3)
28
(10.1)
262
(10.4)
1000
52.0 + 1.5 / - 0.0
(2.05 + 0.06 / - 0.00)
PRODUCT
78
(3.1)
98
(3.9)
260
(10.3)
5000
Dimensions unless specified in mm (inches)
NFR25H
PHOENIX DO BRASIL LTDA
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Phoenix Passive Components
TAPE ON REEL
Table 7. Reel.
PRODUCT
TAPING
M
N
P
Q
V
R
QTY
pcs
NFR25H
52.0 + 1.5 / - 0.0
(2.05 + 0.06 / - 0.00)
92
(3.7)
311
(12.3)
311
(12.3)
305
(12.01)
75
(3.0)
86
(3.4)
5000
Dimensions unless specified in mm (inches)
TESTS AND REQUIREMENTS
Essentially all tests are carried out in accordance to the schedule of IEC publications 60115 - 1, category
55/155/56 (rated temperature range -55 to +155 °C; damp heat, long term, 56 days and along the lines of
IEC publications 60068-2); “Recommended basic climatic and mechanical robustness testing procedure for
electronic components” and under standard atmosphere conditions according to IEC 60068-1 subclause 5.3,
unless otherwise specified.
In some instances deviations from IEC applications were necessary for our method specified.
Table 8. Test and requirements.
IEC
60115-1
CLAUSE
IEC
60068-2
TEST
METHOD
TEST
PROCEDURE
REQUIREMENTS
4.6.1.1
-
Insulation resistance
500 V (DC) during 1 minute;
V-block method
Rins min 104 MΩ
NFR25H
PHOENIX DO BRASIL LTDA
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Phoenix Passive Components
IEC
60115-1
CLAUSE
IEC
60068-2
TEST
METHOD
4.7
4.8
TEST
PROCEDURE
REQUIREMENTS
-
Voltage proof on
insulation
700 (RMS) during 1 minute;
V-block method
No breakdown or flashover
-
Temperature
coefficient
Between
- 55 °C and + 155 °C
0.22 Ω ≤ R ≤ 4.7 Ω
4.7 Ω & lt; R ≤ 15 kΩ
IEC publication 60195
4.12
-
Noise
4.16
21(U)
Robustness of
terminations:
4.16.2
21(Ua1)
Tensile all samples
± 200 ppm/°C
± 100 ppm/°C
& lt; 0.1 µV/V
Load 10 N; 10 s
No damage
∆R/Rmax ±0.25% + 0.05 Ω
4.16.3
21(Ub)
Bending half number
of samples
Load 5 N; 4 x 90°
4.16.4
21(Uc)
Torsion other half
number of samples
3 x 360° in opposite directions
4.17
20(Ta)
Solderability
(after aging)
16 h 155 °C; leads immersed in
flux 600, leads immersed 2 mm
for 2 ±0.5 s in a solder bath at
235 ±5 °C
Good tinning
(≥ 95% covered);
no damage
4.18
20(Tb)
Resistance to
soldering heat
Thermal shock: 3 s;
350 ºC; 6 mm from body
∆R/Rmax ± 0.25% + 0.05 Ω
4.19
14(Na)
Rapid change of
temperature
30 minutes at – 55 °C and
30 minutes at + 155 °C;
5 cycles
No visual damage
∆R/Rmax ± 0.25% + 0.05 Ω
4.22
6(Fc)
Vibration
Frequency 10 to 500 Hz;
displacement 1.5 mm or
acceleration 10 g; three
directions; total 6 h (3 x 2 h)
No damage
∆R/Rmax ± 0.25% + 0.05 Ω
4.23
Climatic sequence:
4.23.2
2(Ba)
4.23.3
Dry heat
30(Db)
Damp heat
(accelerated)
1st cycle
16 h, + 155 °C
24 h, 25 °C to 55 °C,
90% to 100% R.H.
4.23.4
1(Aa)
Cold
2 h, - 55 °C
4.23.6
30(Db)
Damp heat
(accelerated)
remaining cycles
Rins min 103 MΩ
∆R/Rmax ± 1% + 0.05 Ω
5 days; 25 °C to 55 °C;
90 to 98% R.H.
NFR25H
PHOENIX DO BRASIL LTDA
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Phoenix Passive Components
IEC
60115-1
CLAUSE
IEC
60068-2
TEST
METHOD
4.24
TEST
PROCEDURE
REQUIREMENTS
3(Ca)
Damp heat
(steady state)
56 days; 40 ºC; 90 to 95% R.H.;
loaded with 0.01 Pn
Rins min 103 MΩ
∆R/Rmax ± 1% + 0.05 Ω
4.25.1
-
Endurance
(at 70 °C)
1000 h; loaded with Pn or Vmax;
1.5 h ON and 0.5 h OFF.
∆R/Rmax.: ± 1% + 0.05 Ω
4.26
-
Accidental overload
Overload of 5, 10, 16, 25, 40, 63
and 100 times the rated power,
but the applied voltage shall not
exceed four times the limiting
voltage.
Non-flammable
4.29
45(Xa)
Component solvent
resistance
Isopropyl alcohol followed by
brushing in accordance with
MIL STD 202
No visual damage
See 2nd amendment
to IEC 60115-1
Pulse load
See Figs. 7 and 8
NFR25H
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