Sega Saturn Power Supply Components

[mngb123]

Hi,

Can someone help me identify these two components on the Sega Saturn power supply (marked red)? This is a 100V Japanese board. The blue thingy is labelled GNR 050221K and the brown one is 104K 125~G.



Appreciate it. Thanks.

[izarate]

The red one looks like a polyester capacitor. The blue one looks like a capacitor too. The PCB should list their values.

[ooXxXoo]

Is it just me, or that fuse looks blown?..

[mngb123]

Hi izarate, tx for this. nope, the PCB does not list their values... the red one is labeled C01 on the PCB so it is likely a cap. But the blue one is labeled Z01, so I am not sure... doesn't look like a diode to me.

ooxxxoo, yup, the fuse is blown. but the value is clearly printed on the PCB, so had no problem id'ing it.

[FABombjoy]

My guess is the blue thing is an MOV (varistor).

[mngb123]

Tx FABomboy. Any idea what the rating for a capacitor that is labelled 104K 125~G?

[izarate]

Tx FABomboy. Any idea what the rating for a capacitor that is labelled 104K 125~G?

0.1uF 10% 125V

[SkiDragon]

I'd guess the blue one is an inductor based off of the "Z" label.

[mngb123]

izarate, how do you tell the voltage?

[izarate]

ow, sorry. 125V should be the voltage

[mngb123]

tx guys. let me go get the parts and see if i can breathe some life back into the power supply. I will be back...

[Loremaster]

I'd guess the blue one is an inductor based off of the "Z" label.

Definitely not an inductor. After doing a little looking around, I'd agree with FABombjoy, that looks like a Varistor. Can't help you with the value, but at least you know what it is now.

[Jimmy Yakapucci]

I am guessing that power supply is from a model 2. I have a non-working Japanese model 1, so I pulled the power supply from it to see if I could get a better guess at the parts, but mine looks different and doesn't even have component Z01.

JY

[mngb123]

Hey Jim. I got a couple of different model SS. The blue varistor and the fuse is common in all the ones I have. The brown cap, I found it only in this particular one.

[mngb123]

Hi,

I am happy to report good news. Swapped out the blown fuse and the varistor for new ones. The power supply is now alive again! Didn't change out the brown cap because I couldn't find the right replacement but seems that it is still working fine. Thanks for the help everyone. Cheers.

[channelmaniac]

The MOV, or Metal Oxide Varistor, is a component that does not conduct until the voltage differential across the legs reaches a threshhold. When it does, it drops to very low resistance.

MOVs are used for surge protection. Ones with a higher voltage rating than what is input from the wall are used. Say you have 120v inputs... put a 180v or 220v varistor in it. If a surge hits and goes over the 180v then it conducts across the varistor and keeps the surge out of the power supply.

RJ

[mngb123]

RJ, but won't you wanna put an MOV with a voltage rating closer to that of your power supply's voltage rating? Take your example, if I have 120V, isn't it 'better' to keep anything over 120V than say 180V out of the power supply?

[channelmaniac]

Too close and you'll replace it more often. The power supplies are built to handle some surges just fine.

Look at your surge strips in your house. Most of them don't protect until the voltage hits > 300 volts AC.