Fake/Real Nippon Chemi-Con - Page 1
Forum section: electronics / general

author: Matt1234
author_rank: Newbie
timestamp: April 29, 2020, 11:31:24 am
content: Hello. I am not sure if this is the correct section to post this on, but today I ordered and received 2 Nippon Chemi-Con capacitors, 6800 uF, 25 V. Now the first thing I could notice is one of the capacitors has the lighter, brown color than the other one. One of the capacitors had a little bit weird looking text. I will include images so you guys can tell me if those are real. I also would like to know if Nippon Chemi-Con produced any of 6800 uF 25 V capacitors because I can not find any of these online. Please tell me which one is fake, and if the other one is real. If you know also tell me if the 25 V 600 uF ones exist or were produced by Nippon Chemi-Con.The first cap which I think is fake:http://prnt.sc/s7ya3rThe second one which I am not sure about:http://prnt.sc/s7yb9j

author: wraper
author_rank: Unknown
timestamp: April 29, 2020, 12:02:53 pm
content: Either both of them are fake or both genuine since they have exactly the same date/lot code. Issue with text is due to clogged nozzles in printing machine, not necessarily a sign of fake. If you bought them from china on ebay or aliexpress, there is only a small chance to be genuine. You need to provide more pictures, particularly view from top and bottom (from both of them).

author: Matt1234
author_rank: Newbie
timestamp: April 29, 2020, 12:32:00 pm
content: Quote from: wraper on April 29, 2020, 12:02:53 pmTop view:http://prnt.sc/s7zh00Bottom view:http://prnt.sc/s7zjttThank you in advance!

author: wraper
author_rank: Unknown
timestamp: April 29, 2020, 02:14:45 pm
content: They are fake IMHO. Heat-shrink does not look consistent. On genuine NCC it's very precisely applied. You can also rip off the top plastic cover, and see vent style. Genuine cap should have it like on the picture. If it's simply cross, then it's 100% fake.

author: Matt1234
author_rank: Newbie
timestamp: April 29, 2020, 02:49:28 pm
content: Quote from: wraper on April 29, 2020, 02:14:45 pmWhat should I do now? Use them or?

author: SiliconWizard
author_rank: Super Contributor
timestamp: April 29, 2020, 02:51:17 pm
content: Maybe make some firecrackers out of them by polarizing them in reverse...

author: Matt1234
author_rank: Newbie
timestamp: April 29, 2020, 02:53:14 pm
content: Quote from: SiliconWizard on April 29, 2020, 02:51:17 pmWell would they work good as capacitors in the circuit or not?

author: wraper
author_rank: Unknown
timestamp: April 29, 2020, 03:38:09 pm
content: Quote from: Matt1234 on April 29, 2020, 02:53:14 pmThey will work but likely will fail prematurely.

author: Bud
author_rank: Super Contributor
timestamp: April 29, 2020, 04:00:53 pm
content: Did you measure the capacitance ?

author: Matt1234
author_rank: Newbie
timestamp: April 29, 2020, 04:58:10 pm
content: I did not, but should I try to check them?

author: Bud
author_rank: Super Contributor
timestamp: April 29, 2020, 09:06:21 pm
content: Sure, a counterfeit capacitor may be half or less of the stated value.

author: wraper
author_rank: Unknown
timestamp: April 29, 2020, 09:23:42 pm
content: Quote from: Bud on April 29, 2020, 09:06:21 pmMore often they have same capacitance but lower withstanding voltage.

author: SiliconWizard
author_rank: Super Contributor
timestamp: April 29, 2020, 11:01:28 pm
content: If you don't have any fancy equipment, you could sort of test them as follows:- Connect them to a power supply through a series resistor (like 1k ohm or a bit lower), set the power supply to max rated voltage (25V);- This will charge them and eventually get ~25V across them. Leave them like this for a week or so;- Come back and check for any bulging or leak;- Disconnect the power supply, connect the capacitor to an oscilloscope's probe, connect a resistor across the cap to discharge it (ideally through a switch), then put your scope to single shot and close the switch. Now observe the discharge curve, and calculate from it the approximate capacitance. Compare that to the nominal capacitance.This won't tell you if they'll be fine after 10 years of operation, but should give you an idea of how usable they are.And if you don't have patience for that, you can always use them as firecrackers as I suggested. It's more fun than you may think (if you're into firecrackers and things exploding in general.)

author: Matt1234
author_rank: Newbie
timestamp: May 02, 2020, 05:43:35 pm
content: I was also wondering if I should purchase some Nichicon capacitors for my experimental board? I am a 1st-grade electrical engineer and I want to see how capacitors work and how do they smooth things out. I do not know which Nichicon series would be good?

author: james_s
author_rank: Super Contributor
timestamp: May 02, 2020, 05:54:53 pm
content: It probably doesn't matter at all. If you're just experimenting then use whatever capacitors you have. The problem with cheap ones is usually long term reliability, they're fine for prototyping.

author: wraper
author_rank: Unknown
timestamp: May 02, 2020, 06:05:02 pm
content: Quote from: Matt1234 on May 02, 2020, 05:43:35 pmIf you will continue to buy from dodgy places, avoid any 1st tier capacitor brands like chemi-con, nichicon, Rubycon, Suncon/Sanyo since chances of receiving genuine stuff are slim. It's way safer to buy some lesser brand parts.

author: Matt1234
author_rank: Newbie
timestamp: May 02, 2020, 07:00:55 pm
content: To be honest, I was really dissapointed that those were fakes. I ordered 1x Nippon Chemicon 50 V 6800 uF, 2x Nippon Chemicon 25 V 6800 uF, and 6x Samxson 16 V 1000 uF. Instead of Samxson they gave me Elite capacitor, and instead of the real Nippon Chemicons they gave me fake ones... It is my local store and I am dissapointed. Next time I was planning to order from tme.eu. I was ordering from electronic-center.hr

author: wraper
author_rank: Unknown
timestamp: May 02, 2020, 07:08:34 pm
content: Elite are good enough capacitors.