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I need help to find this resistor value. They’re 5 band resistors and it has silver band at 3rd. I try to use online calculator but can't calculate this silver 3rd band.

It’s a faulty resistor so I can’t measure it with a multimeter.

Thank you

enter image description here

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  • \$\begingroup\$ Have you searched the board (or other boards inside) that might have that same resistor color value? \$\endgroup\$
    – Ron Beyer
    Jan 4 at 2:44
  • \$\begingroup\$ There is another one resistor in there. But have different band colour \$\endgroup\$ Jan 4 at 2:47

4 Answers 4

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If you ignore the green band, it all makes sense- 0.82\$\Omega\$ 5%.

The final green band may indicate something like non-inductive, which would be sensible for a low value current sense resistor. It does not appear to be a standardized code. It could also be fusible.

If the current sense resistor is blown up, there is likely some other serious issues such as shorted semiconductors.

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  • \$\begingroup\$ Thanks. I may use that for starting point to find replacement. \$\endgroup\$ Jan 4 at 2:40
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Five band resistors with a fourth band of gold or silver form an exception and are used on specialized and older resistors. The first two bands represent the significant digits, the 3rd is the multiplication factor, the 4th is the tolerance, and the 5th is the temperature coefficient (ppm/˚C).

The third band is the multiplier so it is just grey = 8 , red = 2 , multiplier silver = 0.01 , Tolerance gold = 5% and the temperature coefficient green = 20. So it is 0.82 Ohms.

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  • \$\begingroup\$ Thanks, it help a lot :) \$\endgroup\$ Jan 4 at 14:04
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There's no standardized 5-band resistor color code with silver in the middle. So, this is probably some proprietary marking and only someone who accidentally knows this device can help you. Good luck!

Honestly: resistor looks OK, and it's still soldered in: how could you even determine it is broken? In experience, resistors least likely to break, assume fault in semiconductor, transformer, inductor, capacitor first (in order).

If this being a cheap power supply is right: replace, don't try to repair.

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  • \$\begingroup\$ It doesnt show any value when i measured it, even after i pull it off. Its monitor power supply by the way \$\endgroup\$ Jan 4 at 2:22
  • \$\begingroup\$ @JulianMustofa What does “any value” mean? 0.00 ohm or O.L.? \$\endgroup\$
    – winny
    Jan 4 at 11:32
  • \$\begingroup\$ Its O.L, not shorted. And also the fuse did not blown \$\endgroup\$ Jan 4 at 11:47
  • \$\begingroup\$ @winny and also this resistor rail connected to the source pin at the mosfet transistor. That should make a sense if this power supply did not output voltage \$\endgroup\$ Jan 4 at 11:51
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    \$\begingroup\$ @winny i found out there is a small dot burn mark in the back of this resistor. This is the only visual evidence for this resistor to fail \$\endgroup\$ Jan 4 at 12:47
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Calculate the value of this resistor using the chart below: enter image description here

You can find more details about the calculation using the link below. Hope this helps.

https://www.allaboutcircuits.com/tools/resistor-color-code-calculator/

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  • \$\begingroup\$ Didnt find 3rd silver option at 5 band resistor \$\endgroup\$ Jan 4 at 12:51

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