Electrolytic Capacitors

[Ampdog]

I am not sure where this belongs, as I am not looking for resources but information about usage.

In RSA one seems to mainly find electrolytic capacitors by Hitano, Rubicon and Rec. Full data about Hitano is avaiable both in printed form and on the internet. Most data about Rubicon is on internet (I could not find max. ripple current), while very little about Rec could be found.

As with everything these days quality is an issue. I would like to hear from others about good/bad experiences regarding these or other available makes of electrolytic capacitors. I have been using Hitano with good results, but not many of them. Measurements seem to correspond with quoted data. But I cannot always get what I want in Hitano, and some of my designs need very reliable electrolytics.

Could members kindly comment. please?

Appreciated.

[Shonver]

Most data about Rubicon is on internet (I could not find max. ripple current), while very little about Rec could be found.

Hehe. That's because it is Trec. The company's name is Transcend (electronics corporation?). Blame the confusion on their logo (look again and you'll spot the "T").

IME, Transcend make a good general purpose cap, even some low leakage ones. Hitano also make some low esr caps. IIRC these have gold print. Not too bad. Rubycon are relatively freely available and are my choice of the three. I'm surprised that you could not get max ripple current for them. Perhaps you should try the official distributors (as opposed to a company like Communica). YXB/YXF and MXR are the types you want to look at. For high reliability, use no less that 105deg rated caps, and keep them away from heat sources. There are other types available as well, but usually cost more. Panasonic, Nichicon, Yageo, EPCOS, AVX and Dubilier all have local representation.

I would go to a company like Avnet, Electrocomp or Arrow Altech for advice (they employ applications engineers). This is just off the top of my head. It's about 2 years ago that I was last involved with component sourcing.

HTH, and I hope some of my comments were not too low-level.

[Hi-Phibian]

We use Hitano in a lot of industrial applications in heavy conditions (on public transport busses) and we are not unhappy with their performance at a fair cost. In a repair vs mnf environment or custom build where the labour content is high anyway on a high cost product, the additional cash on Rubycon is probably worth it.

[Ampdog]

Croak,

I hear you. Unfortunately, one often finds one or the other brand stocked, without being able to choose. One could phone; also not always viable. As you probably concluded I sometimes build "high-end" stuff, one-off (thus no bulk purchases), hence my care about quality components for those.

Thanks

[Hi-Phibian]

For one ofs I often use Logitech, they are kind of a wholesaler buying from all the distributors and do some imports themselves. I just hand over a shopping list and pay a few % for removal of hastle. They also break reels on SMD passives for eg.

[Shonver]

As you probably concluded I sometimes build "high-end" stuff, one-off (thus no bulk purchases), hence my care about quality components for those.

Ampdog

I have a had the opportunity to work with some model builders, building one-off scale models (I built an electronic motor speed control). The general trend there was to buy practically everything out of the RS catalogue(!). I was astounded by such extravagance but, after thinking about it, I realised that it made a lot of sense from a supply point of view, especially on time-critical projects.

[Hi-Phibian]

Agree with RS, on one of high value custom projects where chassis, transformers and labour and valves for the thermionically disadvantaged represent the bulk of the "expense" it is twice the price but you get what you order, you get it in max 7 days and if one factors in time spent hunting, driving, lining up at the trade counter etc etc, it is probably competitive. AND you have some assurance of future supply as stocked items are not driven by other bigger customers for that part as with all the other guys.

For eg Rubycon cap stocks at Avnet appear to be lower and lower as more and more of their big clients buy their cheaper brand for non critical applications.

[Shonver]

For eg Rubycon cap stocks at Avnet appear to be lower and lower as more and more of their big clients buy their cheaper brand for non critical applications.

Right. And their stock-holding is driven 99.9% by forecasts from their clients' projected useage for the next year (and often via supply contract). Sometimes, only a maximum quantity is allocated for a specific market by the manufacturer (had this problem with tantalum caps, certain value electrolytics and some photodiodes).

Another supply route that I have not explored in the context of supplying to a business is buying from online (oversees) distributors like Digikey. Only bought from them once for a personal project.

[Ampdog]

Thanks everybody (actually two bodies), much obliged for thr experience of others.

At present I use mostly Hitano ELP/EHP as ripple current is specified. So it is with Epcos, but to do business with that blasted firm .......

I have also used JJ 500V caps from Wim (Mr Valve), but they are quite expensive. Mantech shows a few 500V types but not always in stock; again, I am wary of ripple current and would not like to use unspecified types.

Some experience at my own expense. The other day I connected a Hitano 100uF/450V ELP the wrong way round (EISH!!), and had about 40V across it (going up with a variac) before a fuse mercifully blew. It was a filter input C, directly after a rectifier! It was moderately hot (not to burn the fingers).

After de-shocking myself with some KVW, I let it cool down and carefully reformed with up to 440V through 47K to begin with and progressively lower R (checked current) over several hours. Finally, NO apparent permanent damage! The capacitance checked as before, and the leakage current was below listed value, on par with others. I was impressed (but not with myself).

[Family_Dog]

Some experience at my own expense. The other day I connected a Hitano 100uF/450V ELP the wrong way round (EISH!!), and had about 40V across it (going up with a variac) before a fuse mercifully blew. It was a filter input C, directly after a rectifier! It was moderately hot (not to burn the fingers).

Hmmm... is this what is meant by 'a senior moment'?

 

-F_D

[DevillEars]

Hmmm...   You just brought back a long-forgotten memory from days in Rhodesia...

We used to take large-ish electrolytic capacitors, run a good length (50' or more) of twin flex via a switch and connect to the terminals of the capacitor at one end and at the other plug it into 220v mains...

Duck, fingers in ears, flick the switch and....   KABOOM!  Great teenage fun!  Right up there with Mark VIII Thunderflashes and the like...

[Byrd]

Was thinking of hooking up a couple of them around the exterior of my house, till I moved to Cape Town.

Think that would be an awesome defense mechanism

[Ampdog]

Hmmm... is this what is meant by 'a senior moment'?

 

-F_D

No, it is absent-minded. Defined as "absence of mind". Proving that the fact that there is a gland called a brain keeping the ears a certain distance apart so that one can enjoy stereo, does not mean a thing. It should be capable of the process of thought.

But keep on jesting, F_D. We will see in another 30 years when you reach my age .....

[Family_Dog]

But keep on jesting, F_D. We will see in another 30 years when you reach my age .....

That's the kindest thing anyone has ever said to me this whole year!

Andrew, please give the man a gift subscription! 


-F_D