Seasonic SS-500GB "ticking"

[Uniballer]

Last night I noticed this SS-500GB started making a ticking sound. I made sure it wasn't the fan, then opened it up. I put a tube to my ear (aka redneck stethescope) and the sound appears to be coming from near the toroid by the primary cap. The caps all look OK to the eye. The primary is a Rubycon CE 330uF 450V. Most everything else is United Chemicon KZE series.

The more load is on the power supply the faster the ticking. When I start the power supply with no load it ticks maybe two or three times per second, but it ticks much faster when the entire system is running.

Any clues? Schematics? Advice? Thanks.

[senz_90]

Re: Seasonic SS-500GB "ticking"

Last night I noticed this SS-500GB started making a ticking sound. I made sure it wasn't the fan, then opened it up. I put a tube to my ear (aka redneck stethescope) and the sound appears to be coming from near the toroid by the primary cap. The caps all look OK to the eye. The primary is a Rubycon CE 330uF 450V. Most everything else is United Chemicon KZE series.

The more load is on the power supply the faster the ticking. When I start the power supply with no load it ticks maybe two or three times per second, but it ticks much faster when the entire system is running.

Any clues? Schematics? Advice? Thanks.

i just think that is the "noise" that was filtering, some case other person have a sensitivity to hear that..

[Uniballer]

Re: Seasonic SS-500GB "ticking"

i just think that is the "noise" that was filtering, some case other person have a sensitivity to hear that..

Except that I never noticed it on that machine before, and last night after everybody went home I could hear it from 6 to 8 feet away from the front of the system.

D301 (axial) and D304 (TO220 on the heatsink) both appear good with a DMM diode check.

[Uniballer]

Re: Seasonic SS-500GB "ticking"

D301 (axial) and D304 (TO220 on the heatsink) both appear good with a DMM diode check.

Oops. That's D303 and D304. (how come I can't edit that post anymore?)

BD001 (bridge rectifier) checks out OK.

[domas]

Re: Seasonic SS-500GB "ticking"

Does the supply function as it is supposed? All voltages, ripple (if you have hardware to measure it).

I had a similar issue while i was working on my q-tec adjustable PS (it was outside the case of course). I was ticking at low voltages and buzzing from voltages 10++ at voltages over 12V it was squeaking like crazy and would shut down. I even managed to burn some components like that.

Problem solved by putting it back to the case (grounding). Please check your y-caps.
You can touch GND with your finger while its making sound, if it silences itself then it probably is grounding issue.

[Uniballer]

Re: Seasonic SS-500GB "ticking"

Does the supply function as it is supposed? All voltages, ripple (if you have hardware to measure it).

I reflowed a few solder joints that looked iffy, and the ticking has stopped.

Rather than risk the motherboard again I just put 2 old DVD-RW drives on the supply for a light load. The voltages look OK on my DMM (best one I have here today is a Fluke 117). And checking for ripple with the meter set to AC volts gives about 25 mV. But the scope shows horrible noise bursts about every 13 uS (76.9 kHz) of almost 10V peak to peak but very short duration. A pretty good supply set up with the same load shows less than 90 mV peak to peak. Note to self: you can't check SMPS ripple with a Fluke 117 [edit: I just checked the Fluke site and AC V & mV accuracy is only specified to 1 kHz].

So is that most likely just output filtering on the SS-500GB? I will try to check all the caps, as usual...

[senz_90]

Re: Seasonic SS-500GB "ticking"

Except that I never noticed it on that machine before, and last night after everybody went home I could hear it from 6 to 8 feet away from the front of the system.

D301 (axial) and D304 (TO220 on the heatsink) both appear good with a DMM diode check.

lol. that's bad. yeah u can follow the domas advice that have ever facing same case likes you. i couldn't give you any advicve because i've never face a case likes that. but i think it'll makes easier for everybody to give you advice by post your more detail photograph of PSU here, not just a single photograph that hasn't show the component more closer.. just my opinion.

[Uniballer]

Re: Seasonic SS-500GB "ticking"

I didn't get to work on this supply yesterday, but could I get that ugly noise spike if something is wrong with the snubber diode on the primary side? That makes more sense to me than simply a capacitor problem, especially because the noise seems to be there on all of the main output voltages (didn't check 5VSB).

Also, this is labeled as a 100-240 VAC supply with no voltage range switch (i.e. there is no doubler). When I power the supply from 120 volts I only have about 160 VDC across the primary cap. That seems to make sense, but am I missing something?

And another thing. Does anybody have an opinion on whether increasing the load on the power supply (e.g. putting on an old P4 motherboard I don't care about) might affect the ugly ripple noise?

Thanks for any opinions and/or advice.

[cheapie]

Re: Seasonic SS-500GB "ticking"

When I power the supply from 120 volts I only have about 160 VDC across the primary cap. That seems to make sense, but am I missing something?

When it's on? You should be getting more than that when it's on, since it has APFC.

[Uniballer]

Re: Seasonic SS-500GB "ticking"

Actually, that is when it's off. I'm only reading about 376 VDC across the cap when it's on.

BTW - noise is worse - almost twice as bad - when there is more load (old P4 motherboard).

[cheapie]

Re: Seasonic SS-500GB "ticking"

Actually, that is when it's off. I'm only reading about 376 VDC across the cap when it's on.

That's correct, then.

[Kiriakos GR]

Re: Seasonic SS-500GB "ticking"

Can you compare the symptoms of your PSU, with what is presented in this video ?

http://youtu.be/veTVUhNiRC0




.

[Uniballer]

Re: Seasonic SS-500GB "ticking"

I tested a bunch of parts in-circuit, and wound up pulling some to test out-of-circuit and didn't find anything bad. Ripple meets the ATX V2.2 specs if tested right at the PSU board with a short ground lead.

When I put everything back together and ran an AM2 vintage board running MEMTEST86+ for a couple days I found the power supply was ticking again. My redneck stethoscope said that the source of the noise was the inductor used for the PFC boost converter. I pushed the inductor around with the plastic tube while the supply was running and found a position where it has apparently stopped arcing.

[Uniballer]

Re: Seasonic SS-500GB "ticking"

It's ticking again. Again, moving the inductor stopped it. I pulled the inductor and don't see any burn marks. The glue that was supposed to be holding it in place was clearly not working. Do you think the problem is the inductor itself? The PFC/PWM chip is a CM6800G on a separate little board with a bunch of support components (mainly resistors and caps plus a few diodes). I don't have an LCR meter.

[cheapie]

Re: Seasonic SS-500GB "ticking"

It's ticking again. Again, moving the inductor stopped it. I pulled the inductor and don't see any burn marks. The glue that was supposed to be holding it in place was clearly not working. Do you think the problem is the inductor itself?

Given that you said it was arcing and that moving the inductor stopped it, it's probably the inductor itself.

[Uniballer]

Re: Seasonic SS-500GB "ticking"

Given that you said it was arcing and that moving the inductor stopped it, it's probably the inductor itself.

I'm inferring arcing from the sound, but I didn't actually see any sparks when I watched for them with the lights off.

Any chance of finding a replacement inductor? What do I need to know about this one? I assume wire gauge and inductance. Do I need to know more?
I don't have an LCR meter, is this method reasonably accurate?

[cheapie]

Re: Seasonic SS-500GB "ticking"

Any chance of finding a replacement inductor? What do I need to know about this one? I assume wire gauge and inductance. Do I need to know more?

I believe you also need to get one with the same kind of core. You might want to ask someone more knowledgeable about that.

I don't have an LCR meter, is this method reasonably accurate?

You lost me here:


...but it sounds okay.

[lti]

Re: Seasonic SS-500GB "ticking"

You lost me here:

That's nothing compared to what I've been doing in my electronics class.

[Uniballer]

Re: Seasonic SS-500GB "ticking"

On close examination of the inductor in question I have noticed some blackening between two windings. It is really hard to tell if this is due to arcing, but it is about 120 degrees around from where the leads come off the coil, so I don't see why it would be a purposeful marking. What do you think are the chances of stopping the arcing by re-enameling the wire in this section?

Measuring the inductor using the technique in the link of my prior post I came up with 306 uH (frequency was 14.9 kHz). I counted 69 turns on the toroidal core. Going through Digi-Key fixed inductors I selected a through-hole toroid with 300 uH and radial leads. At that point powdered iron was the only core type I could specify. Selecting by dimensions (I measure about 30mm diameter by 15mm width) and availability I came up with 732-2281-ND. It has a current rating of 3A, but the operating temperature is only -25C to 85C. Does this sound right for an 80% efficient 500 watt power supply? Anybody got a better choice that I could actually buy? Or do I have this all wrong?

[Uniballer]

Re: Seasonic SS-500GB "ticking"

3A seems too low (input voltage peak is 160V, 625W/160V = 3.9A). Maybe M8892-ND is a better fit.