Revision 200807
VITROHM PORTUGUESA, Lda. - Est.Nacional 249-4, Trajouce - 2765-653 S. Domingos de Rana - PORTUGAL
Tel: + 351 214 457 700 -Fax: + 351 214 457 755 -Germany Sales Tel: + 0049 4121 870 103 - e-mail:vitrohm.support@yageo.com - www.vitrohm.com
Series BWF
Insulated Wirewound Resistors, moulded
flame retardant, failsafe
Specifications
BWF237-0
BWF236-0
Type
[
∆
R
]
R
[
∆
R
]
R
[
∆
R
]
R
[
∆
R
]
R
[
∆
R
]
R
Style
0411
0614
Power rating P
70
W
0,75 (P
50
= 1,0)
1,5 (P
25
= 2,0)
Resistance range
Ω
0R1 ... 1K
0R1 ... 1K
E-Series
E 24, E 12
Tolerances
%
± 5, ± 10
Temperature coefficient
10
-6
* K
-1
- 400 ... + 1000, see table next page
max. cont. work. voltage
V
RMS
√
P
70
· R
Insulation voltage (1min.)
V
RMS
700
1000
Insulation resistance
Ω
> 10
4
M
Derating linear
o
C
70 ... 175 (0W)
Climatic category
55/175/56
Temperature range
o
C
- 55 ... 175
Thermal resistance
KW
-1
140
80
Failure rate
(Total,
ϑ
o
max., 60% conf. lev.) 10
-9
* h
-1
appr. 100, depends on value
Endurance
(P
70
, 1000h)
%
± 5,0 average
± 10,0 average
Damp heat, steady state
(40
o
C, 93% r.h., 56d)
%
± 2,0
Climatic sequence
%
± 2,0
Terminal strength
%
± 1
Terminal tensile strength
N
40
Resistance to soldering heat
(260
o
C, 10s)
%
± 0,2 typ.
Solderability
s 2,5 Flowtime, solderglobule test, IEC 60068-2-20-T
Marking
DIN-IEC-colour code, 5 bands
(5th band (blue) for failsafe version)