High quality Hermei caps?!

[Pentium4]

I have a Viewsonic VP191B here that was making a weird whining sound when in standby, so I figured bad caps. It was manufactured on 7/24/04. I open it up and find all good Japanese caps on the power board, Taicon on the main board, and HERMEI LZ series on the inverter board. I tested these two Hermei caps 180uF 30V caps (Isn't that a strange value?) and they read 178.6uF 0.07Ω ESR, and 179.7uF 0.07Ω ESR. Look how hot that board got, and it's almost a decade old...How the hell did they last so long and stay perfectly in spec?!

[ant3202]

Re: High quality Hermei caps?!

no bloat does not mean it is not bad.

[Wester547]

Re: High quality Hermei caps?!

The thing about the Taiwanese capacitor manufactures is that they are not consistent in quality. They are not guaranteed to fail, just that their failure rate is high enough and unpredictable enough that preemptive replacement is admonished. I think lti had a Hipro 250W Dell that ran 9 years with 24/7 use and almost none of the Asiacon capacitors bloated even after the fan seized for a while because the thermistor was loose. On the other hand, you can see a bloated Asiacon LE 4700uF/10V on the +5V rail of this Hipro 250W that had a noisy ADDA fan which hadn't yet seized: http://www.youtube.com/watch?v=pgo3aEMMsyY However, unlike the Chinese capacitors, which are really crappy, at least the 'mediocre' Taiwanese brands will last if kept very cool.

Also of note that Asiacon/Hermei share the same parent company as Jamicon does (Kaimei) if that speaks anything of their quality. But of course that probably means little as Taicon is a subsidiary of Nichicon and we all know their quality is not the same at all... no, I wouldn't say those are high quality. In fact, heat is the enemy of all lytics, Japanese included. Only conductive/truly solid polymers are resistant to it.

[Pentium4]

Re: High quality Hermei caps?!

no bloat does not mean it is not bad.

I know this, but they obviously tested good. Within 1% of spec

The thing about the Taiwanese capacitor manufactures is that they are not consistent in quality. They are not guaranteed to fail, just that their failure rate is high enough and unpredictable enough that preemptive replacement is admonished. I think lti had a Hipro 250W Dell that ran 9 years with 24/7 use and almost none of the Asiacon capacitors bloated even after the fan seized for a while because the thermistor was loose. On the other hand, you can see a bloated Asiacon LE 4700uF/10V on the +5V rail of this Hipro 250W that had a noisy ADDA fan which hadn't yet seized: http://www.youtube.com/watch?v=pgo3aEMMsyY However, unlike the Chinese capacitors, which are really crappy, at least the 'mediocre' Taiwanese brands will last if kept very cool.

Also of note that Asiacon/Hermei share the same parent company as Jamicon does (Kaimei) if that speaks anything of their quality. But of course that probably means little as Taicon is a subsidiary of Nichicon and we all know their quality is not the same at all... no, I wouldn't say those are high quality. In fact, heat is the enemy of all lytics, Japanese included. Only conductive/truly solid polymers are resistant to it.

I just found it amazing, because it was used daily for almost a decade

[Agent24]

Re: High quality Hermei caps?!

I have a Viewsonic VP191B here that was making a weird whining sound when in standby, so I figured bad caps. It was manufactured on 7/24/04. I open it up and find all good Japanese caps on the power board, Taicon on the main board, and HERMEI LZ series on the inverter board. I tested these two Hermei caps 180uF 30V caps (Isn't that a strange value?) and they read 178.6uF 0.07Ω ESR, and 179.7uF 0.07Ω ESR. Look how hot that board got, and it's almost a decade old...How the hell did they last so long and stay perfectly in spec?!

I have exact same thing in my HP f1903 - whining sound in standby. Got it second hand so I don't know if I did that when it was new.

Taicon on mainboard, Rubycon in PSU, and Inverter has Hermei LZ and both tested OK. Replaced them with Panasonic anyway. Left everything else.

Still makes the noise, don't know why.

[momaka]

Re: High quality Hermei caps?!

The thing about the Taiwanese capacitor manufactures is that they are not consistent in quality. They are not guaranteed to fail, just that their failure rate is high enough and unpredictable enough that preemptive replacement is admonished.

^ That's probably the most accurate description of cheap capacitors.
I had Hermei HT capacitors kill a WRT54G router because one of them failed terribly.

On the other hand, I think I also had an inverter from an LCD monitor with these Hermei LZ caps, and both appeared to be good visually, even though they were in a very hot area of the board.

I still don't trust Hermei, though.

[PanicMechanic]

Re: High quality Hermei caps?!

Hemei LZ (680uF, 16V, low ESR, 105oC) caps fails after 2 years in multiple Asus WiFi routers (same model).