BCcomponents
DATA SHEET
AC01/03/04/05/07/10/15/20
Cemented wirewound resistors
Product specification
Supersedes data of 17th November 1998
File under BCcomponents, BC08
2000 Oct 20
BCcomponents
Product specification
Cemented wirewound resistors AC01/03/04/05/07/10/15/20
FEATURES
DESCRIPTION
The resistor element is a resistive wire
which is wound in a single layer on a
ceramic rod. Metal caps are pressed
over the ends of the rod.
The ends of the resistance wire and the
leads are connected to the caps by
welding. Tinned copper-clad iron
leads with poor heat conductivity are
employed permitting the use of
relatively short leads to obtain stable
mounting without overheating the
solder joint.
The resistor is coated with a green
silicon cement which is not resistant to
aggressive fluxes. The coating is
non-flammable, will not drip even at
high overloads and is resistant to most
commonly used cleaning solvents, in
accordance with
“MIL-STD-202E,
method 215”
and
“IEC 60068-2-45”.
•
High power dissipation in
small volume
•
High pulse load handling
capabilities.
APPLICATIONS
•
Ballast switching
•
Shunt in small electric motors
•
Power supplies.
QUICK REFERENCE DATA
DESCRIPTION
Resistance range
VALUE
AC01
0.1
Ω
to
2.4 k
Ω
=
AC03
0.1
Ω
to
5.1 k
Ω
AC04
0.1
Ω
to
6.8 k
Ω
AC05
0.1
Ω
to
10 k
Ω
AC07
0.1
Ω
to
15 k
Ω
AC10
0.68
Ω
to
27 k
Ω
AC15
0.82
Ω
to
39 k
Ω
AC20
1.2
Ω
to
56 k
Ω
Resistance tolerance
Maximum permissible body temperature
Rated dissipation at T
amb
= 40
°
C
Rated dissipation at T
amb
= 70
°
C
Climatic category (IEC 60 068)
Basic specification
Stability after:
load, 1000 hours
climatic tests
short time overload
1W
0.9 W
3W
2.5 W
4W
3.5 W
2000 Oct 20
=
±
5%; E24 series
350
°
C
5W
4.7 W
7W
5.8 W
10 W
8.4 W
15 W
12.5 W
20 W
16 W
40/200/56
IEC 60115-1
∆
R/R max.:
±
5% + 0.1
Ω
∆
R/R max.:
±
1% + 0.05
Ω
∆
R/R max.:
±
2% + 0.1
Ω
2
BCcomponents
Product specification
Cemented wirewound resistors
ORDERING INFORMATION
Table 1
Ordering code indicating resistor type and packaging
AC01/03/04/05/07/10/15/20
ORDERING CODE 23.. ... .....
TYPE
LOOSE IN BOX
STRAIGHT LEADS
100 units
AC01
AC03
(1)
AC04
(1)
AC05
(1)
AC07
(1)
AC10
AC15
AC20
Notes
1. Products with bent leads and loose in box, are available on request.
2. Last 3 digits available on request.
Ordering code (12NC)
Table 2
Last digit of 12NC
LAST DIGIT
7
8
9
1
2
3
O
RDERING EXAMPLE
The ordering code of an AC01 resistor,
value 47
Ω
, supplied in ammopack of
1000 units is: 2306 328 33479.
Product specifications deviating
from the standard values are available
on request.
RADIAL
2 500 units
06 328 90...
(2)
BANDOLIER IN AMMOPACK
STRAIGHT LEADS
500 units
1 000 units
06 328 33...
−
−
−
−
−
−
22 329 15...
22 329 20...
−
22 329 03...
22 329 04...
22 329 05...
22 329 07...
22 329 10...
−
−
−
−
−
−
−
−
−
−
−
−
−
−
−
−
•
The resistors have a 12-digit
ordering code starting with 23
•
The subsequent 7 digits indicate the
resistor type and packaging;
see Table 1.
•
The remaining 3 digits indicate the
resistance value:
– The first 2 digits indicate the
resistance value.
– The last digit indicates the
resistance decade in accordance
with Table 2.
RESISTANCE
DECADE
0.1 to 0.91
Ω
1 to 9.1
Ω
10 to 91
Ω
100 to 910
Ω
1 to 9.1 k
Ω
10 to 56 k
Ω
2000 Oct 20
3
BCcomponents
Product specification
Cemented wirewound resistors
FUNCTIONAL DESCRIPTION
Product characterization
AC01/03/04/05/07/10/15/20
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”.
Limiting values
LIMITING VOLTAGE
(1)
(V)
1
3
4
V
=
P
n
×
R
5
7
10
15
20
LIMITING POWER
(W)
T
amb
= 40
°
C
T
amb
= 70
°
C
0.9
2.5
3.5
4.7
5.8
8.4
12.5
16.0
TYPE
AC01
AC03
AC04
AC05
AC07
AC10
AC15
AC20
Note
1. The maximum voltage that may be continuously applied to the resistor element, see
“IEC publication 60266”.
The maximum permissible hot-spot temperature is 350
°
C.
D
ERATING
The power that the resistor can dissipate depends on the operating temperature; see Fig.1.
100
Pmax 90
(%)
50
MRA574
0
40
0
40
70
Tamb (
o
C)
200
Fig.1 Maximum dissipation (P
max
) as a function of the ambient temperature (T
amb
).
2000 Oct 20
4
BCcomponents
Product specification
Cemented wirewound resistors
P
ULSE LOADING CAPABILITIES
AC01/03/04/05/07/10/15/20
How to generate the maximum allowed pulse-load from the graphs composed for wirewound resistors of the AC-types.
Single pulse condition; see
Fig.3
1. If the applied pulse energy in Joules or Wattseconds is
known and also the R-value to be used in the
application; take the R-value on the X-axis and go
vertically to the curved line. From this point go
horizontally to the Y-axis, this point gives the maimum
allowed pulse energy in Joules/ohm or Wattsec./ohm.
By multiplying this figure with -value in use gives the
maximum allowed pulse-energy in Joules or Wattsec. If
this figure is higher than the applied pulse-energy the
application is allowed. Otherwise take one of the other
graphs belonging to AC-types with higher P
n
.
2. If, contrary to the information above, the applied
peak-voltage and impulse times t
i
are known. Calculate
the pulse-energy (E
p
) in Joules or Wattsec. by the use of
the following formula:
Vp
-
Ep
=
---------
×
t
i
(V
p
= peak voltage; t
i
= impulse-time)
R
By dividing this result with the R
n
-value of the R in use,
gives the value Wattsec./ohm on the Y-axis. Draw a line
horizontally to the curved line and at the intersection
the vertical line to the X-axis gives the maximum
allowed R
n
-value to be used in the application. If this
R
n
-value is higher than the R-value to be used in the
application, the application is allowed. If not, take one
of the other graphs belonging to AC-types with higher P
n
or change the R
n
-value to be used.
2
Repetitive pulse condition; see
Fig.2
With these graphs we can determine the allowed
pulse-energy in Watts depending on the impulse- time t
i
and
the repetition time t
p
of the pulses. The parameter is the
Resistance Value. If the pulse shape is known (impulse-time
t
i
and repetition time t
p
), draw a line vertically from the
X-axis at the mentioned t
i
to the line of the involved R-value.
From the intersection the horizontal line to the Y- axis
indicates the maximum allowed pulse-load at a certain t
p
/t
i
.
If the vertical line from the X-axis crosses the applied t
p
/t
i
before reaching the R-line, this t
p
/t
i
line gives the maximum
allowed pulse-energy at the Y-axis. If the applied
pulse-energy is known (in Watts) and the impulse-time t
i
also, draw a line horizontally from the Y-axis to the crossing
with the pulse-line (t
i
) and find the possible R-value needed
in this application. The horizontal t
p
/t
i
lines give the
maximum allowed pulse-load till they reach the R-line, that
point indicates the maximum allowed impulse-time ti at the
horizontal axis.
2000 Oct 20
5