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I changed a resistor with same color stripes Yellow, Purple, Gold, Gold on a Pioneer surround system but the only difference was that the I put was a bit bigger. The problem is the system went into protected mode because of an error, I forced reset it and the fuse blew up. Was it because of the resistor I changed?

UPDATE: It was not a fuse that blew up, It was 2 of D5SBA60 silicon bridge rectifier that blew up. There is leakage from there.

I have pics of the 2 silicon bridge rectifiers and the resistor that I changed:

To me it looks like it has leaked?

enter image description here

I measured this resistor in ohms and only shows open line, other one is ok, about 5 ohms. I will be replacing it for a good one, to me it looks like it leaked.

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    \$\begingroup\$ You could have the tail wagging the dog: A blown component that you see may result from another unseen fault. Such incomplete troubleshooting may result in cascading failures. \$\endgroup\$ – glen_geek Nov 25 '18 at 14:19
  • \$\begingroup\$ Perhaps something shorted the power supply like a loose screw? \$\endgroup\$ – JBaczuk Nov 27 '18 at 18:57
  • \$\begingroup\$ Do you mean like a screw that fell and made contact or a screw that was not in all the way? Im thinking it could be either. But not sure, the rectifier both have screws in the middle to keep it cool. Otherwise I did not know how important it was to have them all screwed, I was only going to test. \$\endgroup\$ – Alejandro H Nov 27 '18 at 23:19
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Is a bigger resistor different from a smaller resistor with same color stripes?

In general, a resistor can be characterized by three values:

  • The resistance
  • The maximum allowed power
  • The behavior (change of resistance) when the resistor gets heated

The color stripes tell you about the resistance (and about the tolerance of that value). So if the color stripes are the same, the resistor has the same resistance.

If the resistor's maximum allowed power is too small, the resistor will heat up and may be destroyed (e.g. burn). There is no problem if the resistor's maximum allowed power is higher than required. Although this is not sure I would expect that a "bigger" resistor allows more power than a smaller one.

Typically you can forget about the behavior when the resistor gets heated.

The problem is the system went into protected mode because of an error, I forced reset it and the fuse blew up. Was it because of the resistor I changed?

You didn't change the resistor just for fun but because your system did not work any more.

In this case you can nearly be sure that the resistor was not the only part that was destroyed.

If you only change the resistor, the other parts that were destroyed still are destroyed. I guess that these parts caused the fuse to be blown - not the resistor.

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  • \$\begingroup\$ There's also a voltage rating. 10MOhm and 1000V give just 10mW, but the voltage would not care about a 0603 resistor and just jump over. \$\endgroup\$ – sweber Nov 25 '18 at 9:28
  • \$\begingroup\$ UPDATE: It was not a fuse that blew up, it was 2 of D5SBA60 silicon bridge rectifier that blew up. I know because there was leakage from there. \$\endgroup\$ – Alejandro H Nov 25 '18 at 16:37
  • \$\begingroup\$ Ok, the problem was the speaker output volume was too low, and I read AC voltage and that speaker has lower voltage than all other speaker output. So, I would assume that a bad capacitor caused the resistor and rectifier to go bad? \$\endgroup\$ – Alejandro H Dec 3 '18 at 1:03
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The problem is the system went into protected mode because of an error, I forced reset it and the fuse blew up. Was it because of the resistor I changed?

Well, you could have inadvertently changed the resistor for an inductor: -

enter image description here

Or you could have assumed that the component was a resistor when in fact it was an inductor. Either way might cause problems.

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  • \$\begingroup\$ I checked and it was specifically a fireproof resistor. \$\endgroup\$ – Alejandro H Nov 25 '18 at 14:29
  • \$\begingroup\$ I'm unsure what a fireproof resistor and and, how did you check it? \$\endgroup\$ – Andy aka Nov 25 '18 at 16:31
  • \$\begingroup\$ correction *flameproof resistor, 1.2w 4.7 ohm 5% NTE, its labeled, I got it from frys. Also I need to update info, it was not a fuse that blew up, it was 2 of D5SBA60 silicon bridge rectifier. \$\endgroup\$ – Alejandro H Nov 25 '18 at 16:36
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Typically the larger the resistor, the more power it can handle. For example:

Image of different resistor sizes and power ratings

(Image source)

That, however, would not be the source of the problem you are experiencing, because higher power rating at the same resistance just means the resistor is less likely to blow.

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