Need help identifying electronic component

jamesleung79

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Hey,
Does anyone know for certain what the component in the attached photos is?
There are several of them on the PCB and they're all labeled SGxxxx. I dont know what "SG" is supposed to be... I havent seen that before. On the solder side they've also got a symbol I dont recognize (circular silkscreened one).

Thanks for any help you can provide.
 

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Heya Dokert,
I've attached another picture with the item in question circled in red. Are you sure you're talking about that component? Below that is a grounding screw point...

The circled component is present in several locations, some nowhere near a grounding screw. They also have varying colored stripes, which must indicate their ratings, just like resistors do.
 

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Heya Dokert,
I've attached another picture with the item in question circled in red. Are you sure you're talking about that component? Below that is a grounding screw point...

The circled component is present in several locations, some nowhere near a grounding screw. They also have varying colored stripes, which must indicate their ratings, just like resistors do.

Sorry, I was looking at the center of the picture. That appears to be the cap in question.

SC has a good point, what chassis is it?
 
It's the power supply board from an LCD panel that's in a Street Fighter 4 cab. The board is a DPS-178AP. The panel itself is a Sharp Aquos LCD.
 
Ken, I think you're onto something. I figure it's gotta be like some sort of a fuse. I took it out of the circuit and it's wide open. The others on the board are all closed/pass continuity tests. Looking very closely at one end, it looks like it popped a little... maybe letting out the gas and breaking the connection?

Do you have any idea how I can read the band markings to get the right replacement part? Mouser seems to carry various surge arrestors, but I have no idea what ratings would be appropriate.
 
SG = Spark Gap. A type of surge arrester to protect things.

It *will* read open. When the voltage is high enough it will jump across the gap.
 
Ken, I think you're onto something. I figure it's gotta be like some sort of a fuse. I took it out of the circuit and it's wide open. The others on the board are all closed/pass continuity tests. Looking very closely at one end, it looks like it popped a little... maybe letting out the gas and breaking the connection?

Do you have any idea how I can read the band markings to get the right replacement part? Mouser seems to carry various surge arrestors, but I have no idea what ratings would be appropriate.

The ones on the board read closed because they're in parallel with inductors, and the inductors read open. They're there to shunt out surges that would otherwise damage the inductors.
 
Excellent information guys, thanks! I removed another of those spark gaps, and they do indeed test open out of circuit.

I guess my hunt for the problem continues.
 
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