Tdk 614-003

[lopaka1998]

I've got an old TDK power supply out of an old Macintosh LC III.

On the low voltage side there are 4 Nichicon PL series caps. There are also 4 other Elna RSG series caps with a 9240 date code. I can easily replace the Nichicon PL with Nichicon PM series. I can't seem to find a specsheet on the elna caps. Are they reasonably equivalent to Nichicon PL (and therefore replaceable with the PM series)?

Are there better caps I could put in there other than Nichicon PM?

Also on the high voltage side are two electrolytic caps. I've been able to find their datasheet - but the specific voltage/capacitance ratings don't quite match up.

Notice in the below picture - a Nichicon LQ series cap. It's rated at 180uf, 385 volts. The spec sheet has a 400 volt. What happened to 385? If I use the LS series as a replacement... would this be an acceptable replacement - or is this a custom cap - in which case I might need something else.

The other capacitor (right next to the LQ cap) - Nichicon PF series is 8.2uf 50v, but the spec sheet (and the PJ series I want to use to replace it) both don't show 8.2 uf - only 6.4 or 10uf. Again - is this a custom cap - should I just use the 10uf - or perhaps there's something better I could put there.


Thoughts please.

[kholk]

Re: Tdk 614-003

I don't think there are custom caps... btw, I'm not an electronics expert and I came here for a problem myself.

BTW, as for your problem with the ELNA RSG capacitors, I think I may have solved your situation. I just found a capacitor cross reference from year 2000 that should be reporting equivalent capacitors from various manufacturers and series.

That means you could find the specs of those equivalent capacitors and find a new one that will suit.

Personally, I've replaced the caps in my PSU with Panasonic caps (one FR, others FC).


Here's the doc:

[Behemot]

Re: Tdk 614-003

Can't see any pic

[PeteS in CA]

Re: Tdk 614-003

Nichicon's PM series is the RoHS version of the PL series. And the Elna RSG series crosses to the PL series. You can use PM, obviously. If availability is an issue: the next step better would be Nichicon PJ or UCC LXV; the next step better from those would be Nichicon PW or UCC LXZ. Without looking at a datasheet, I don't know if LXZ or PW would be a good idea.

[lopaka1998]

Re: Tdk 614-003

Nichicon's PM series is the RoHS version of the PL series. And the Elna RSG series crosses to the PL series. You can use PM, obviously. If availability is an issue: the next step better would be Nichicon PJ or UCC LXV; the next step better from those would be Nichicon PW or UCC LXZ. Without looking at a datasheet, I don't know if LXZ or PW would be a good idea.

Thanks. That helped.

One last question - the Nichicon LQ capacitor is 385 volt but there is no 385 volt in the datasheet. Also the Nichicon PF cap is 8.2uf, but the datasheet only shows 6.4 and 10uf. Why? You can see what I mean by looking at their current equivalent datasheets - LS series and PJ series. It's nearly the same.

As for the person who couldn't see the picture - I can see it. It's hosted on bayimg.com. Maybe that domain is blocked in your area? I'll try to find a better image hosting provider for next time.

[Behemot]

Re: Tdk 614-003

Can see it now. Are you really sure it is bad/bulging? Or why do you want to replace it?

[lopaka1998]

Re: Tdk 614-003

Can see it now. Are you really sure it is bad/bulging? Or why do you want to replace it?

Yes, it's bad. It's leaking from the bottom. You can't see it in the pic. I'm not surprised. It's 20 - 22 years old, only rated 85c/1000 hours and had well over 1000 hours of use - I wouldn't be surprised if it was many times that, easily. I didn't think Nichicon's bulge often - unless of course a bad batch is made or a catastrophic failure of other components have occurred.

Can anyone here answer my above question - Why is the 385 volt LQ and the 8.2uf PF cap not specified in the datasheet?

The reason I ask is that I want to know whether or not the LS series 400 volt 180uf would be mostly the same. I also want to verify the 10uf PJ series used to replace the 8.2uf PF series cap wouldn't be a problem. And of course also the curiosity... Why have a cap value that's not listed? If it's a customized capacitor, does it have customized specifications? I guess that's the real real question I've been trying to get to. The LQ is 30 mm diameter x 25 mm high in size.

[budm]

Re: Tdk 614-003

You can use the 400VDC rating as long as it fit into the board, you also need to look at the Ripple current rating, you want it to be the same or higher. The 8.2uF is an odd size, unless it is used for timing, then 10uF can be used since lytics cap has 20% tolerance. There are many improvement have been made to the caps these day.

[Behemot]

Re: Tdk 614-003

Can only see one pic, maybe I am missing something but it only seems to me it may be slightly bulging, that's all.

Anyway, I think you can get more capacity, more ripple, higher temperature, longer life and higher voltage in the same package today.