|
| Metal Film Resistors |
Introduction:
The WM series Metal Film Resistors are manufactured using the
latest Magnetron Vaccum Sputtering System. This ensures a very
stable resistive medium having a very low temperature coefficient.
The resistors are insulated with layers of light blue lacquer.
The WM series offer a wide range of power rating (0.20W, 0.25W,
0.35W, 0.50W, 1W, 2W & 3W), tolerances (1%, 2%, 5%) and
TCRs (25, 50, & 100 ppm). |
| |
|
| S
p e c i f i c a t i o n s |
| Type
No. |
WM12 |
WM25M |
WM25 |
WM50
WM50M |
WM100
WM100M |
WM
200
WM 200M |
WM
300M |
| Rated
Power at 70oC |
0.20W |
0.25W |
0.35W |
0.5W |
1W |
2W |
3W |
| Resistance
Range |
10
E to 1 meg |
10
E to 1 meg |
10
E to 1 meg |
10
E to 1 meg |
10
E to 1 meg |
10
E to 1 meg |
10
E to 1 meg |
| Max.
working voltage to 70oC at normal air pressure |
200V |
250V |
250V |
350V |
500V |
500V |
500V |
| Operating
Temperature Range |
-40oC
+ 150oC |
-40oC
+ 150oC |
-40oC
+ 150oC |
-40oC
+ 150oC |
-40oC
+ 150oC |
-40oC
+ 150oC |
-40oC
+ 150oC |
| T C R
R a n g e |
| Tolerance Range |
1% |
2% |
5% |
| TCR Range (ppm/oC) |
25/50/100 |
50/100 |
100 |
| C h a r a c t e r i
s t i c s |
| Type No. |
WMO 12 |
WM 25/WM25M |
WM 50/WM 50M |
WM 100/WM 100M |
WM 200/WM 200M |
WM 300M |
| Dielectric Strength |
450V No break down
 R
max. 0.5% |
500V No break down
R
max. 0.5% |
700V No break down
R
max. 0.5% |
1000V No break down
R
max. 0.5% |
1000V No break down
R
max. 0.5% |
1000V No break down
R
max. 0.5% |
| Terminal Strength |
no damage
R
max. 0.5%
|
no damage
R
max. 0.5%
|
no damage
R
max. 0.5%
|
no damage
R
max. 0.5%
|
no damage
R
max. 0.5%
|
no damage
R
max. 0.5% |
| Resistance to soldering heat (350oC) |
R
max. 1% |
R
max. 1% |
R
max. 1% |
R
max. 1% |
R
max. 1% |
R
max. 1% |
| Solderability |
good tinning
no damage |
good tinning
no damage |
good tinning
no damage |
good tinning
no damage |
good tinning
no damage |
good tinning
no damage |
| Temperature Cycling -40oC to 150oC |
good tinning
R
max. 0.25% |
good tinning
R
max. 0.25% |
good tinning
R
max. 0.25% |
good tinning
R
max. 0.25% |
good tinning
R
max. 0.25% |
good tinning
R
max. 0.25% |
| Life 1000 hours at rated Power |
R
max. 1% |
R
max. 1% |
R
max. 1% |
R
max. 1% |
R
max. 1% |
R
max. 1% |
| Short time overloaded |
R
max. 0.5% |
R
max. 0.5% |
R
max. 0.5% |
R
max. 0.5% |
R
max. 0.5% |
R
max. 0.5% |
| Vibration |
no damage
R
max. 0.5%
|
no damage
R
max. 0.5%
|
no damage
R
max. 0.5%
|
no damage
R
max. 0.5%
|
no damage
R
max. 0.5%
|
no damage
R max.
0.5% |
| Resistance to solvents |
no damage |
no damage |
no damage |
no damage |
no damage |
no damage |
 |
| Standard Resistance Values |
| E 24 S e r i e s |
| 10 |
11 |
12 |
13 |
15 |
16 |
18 |
20 |
22 |
24 |
27 |
30 |
| 33 |
36 |
39 |
43 |
47 |
51 |
56 |
62 |
68 |
75 |
82 |
91 |
| E
96 S e r i e s |
| 100 |
102 |
105 |
107 |
110 |
113 |
115 |
118 |
121 |
124 |
127 |
130 |
133 |
137 |
140 |
143 |
| 147 |
150 |
154 |
158 |
162 |
165 |
169 |
174 |
178 |
182 |
187 |
191 |
196 |
200 |
205 |
210 |
| 215 |
221 |
226 |
232 |
237 |
243 |
249 |
255 |
261 |
267 |
274 |
280 |
287 |
294 |
301 |
309 |
| 316 |
324 |
332 |
340 |
348 |
357 |
365 |
374 |
383 |
392 |
402 |
412 |
422 |
432 |
442 |
453 |
| 464 |
475 |
487 |
499 |
511 |
523 |
536 |
549 |
562 |
576 |
590 |
604 |
619 |
634 |
649 |
665 |
| 681 |
698 |
715 |
732 |
750 |
768 |
787 |
806 |
825 |
845 |
866 |
887 |
909 |
931 |
953 |
976 |
| D i m e n s i o n s
i n m m |
| TYPE WM 12/WM 25M |
H = 28 
1 |
L = 3.4
0.2 |
D = 1.8
0.1 |
d = 0.48
0.02 |
| TYPE WM 25/WM 50M |
H = 28
1 |
L = 6.0
0.4 |
D = 2.3
0.1 |
d = 0.55
0.02 |
| TYPE WM 50/WM 100M |
H = 28
1 |
L = 9.5
0.5 |
D = 3.2
0.2 |
d = 0.6
0.02 |
| TYPE WM 100/WM 200M |
H = 28
1 |
L = 11
1.0 |
D = 4.3
0.5 |
d = 0.7
0.04 |
| TYPE WM 200 |
H = 28
1 |
L = 16
1.0 |
D = 5.0
0.5 |
d = 0.8
0.04 |
| TYPE WM 300M |
H = 28
1 |
L = 16
1.0 |
D = 5.0
0.5 |
d = 0.8
0.04 |
|
| Colour |
1st Figure |
2nd Figure |
3rd Figure |
multiplier |
Tolerance |
| Black |
0 |
0 |
0 |
0 |
|
| Brown |
1 |
1 |
1 |
10 |
1% |
| Red |
2 |
2 |
2 |
100 |
2% |
| Orange |
3 |
3 |
3 |
1,000 |
|
| Yellow |
4 |
4 |
4 |
10,000 |
|
| Green |
5 |
5 |
5 |
100,00 |
0.5% |
| Blue |
6 |
6 |
6 |
1,000,000 |
0.25% |
| Violet |
7 |
7 |
7 |
10,000,000 |
|
| Gray |
8 |
8 |
8 |
|
0.1% |
| White |
9 |
9 |
9 |
|
|
| Gold |
|
|
|
0.1 |
5% |
| Silver |
|
|
|
0.01 |
10% |
|
 |
| |
|
|
| |
|