As with any new product, before we offered them up for sale we tested our first shipment of these relays that came in the door. Looking on the internet, it quickly became obvious that there have been a lot of complaints about these parts failing. Since the manufacturer FOTEK is considered to be a good quality manufacturer overall, the common conjecture is that the failing parts are counterfeit and therefore presumably of inferior construction. There are other items that may be tip-offs as well such as the sloppiness of the print around the LED, flat vs textured appearance of the label stock etc. Here is a link to a UL notice released several years ago about fraudulent use of the UL logo that calls out some of the signs of fakes that were identified at that time. UL Link.
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Not too long ago we had a serious warranty issue with some of the controllers we manufacture. The controllers were passing test and would initially work for our customers, but would eventually fail.
And these failures occurred after a long run of controllers that did not fail, so I knew that something had changed. One change we made was we switched from buying directly from a known Chinese supplier to buying through USA based suppliers selling on Amazon.
I had been watching prices for a while and my cost through Amazon. I did a quick online search and discovered that the part is rated at a continuous load of 12 Amps and a non-repetitive load of Amps. I did a quick online search and discovered that the part is rated at a continuous load of 20 Amps and a non-repetitive load of Amps. And even though some of the counterfeit claims are likely failures caused by improper installation, apparently counterfeit SSRs are quite a problem!
Yes there are and here is their Web Site. If you decide to buy any brand SSR from any online supplier including Amazon, eBay or "Joe's SSR Shop" not licensed to sell the product you are basically making a "shot in the dark" purchase. I mentioned earlier that even the counterfeit SSRs were built well.
All of the soldering was high quality and the TRIAC was properly mounted to the back plate with plenty of thermal grease. I suspect that these counterfeits are nothing more than lower current models re-labeled as higher current models.
If this weren't so I believe the counterfeits I disassembled would be poorly built. There is a huge financial motivation to do this. Lower current models cost less than higher current models and any re-labeled product would result in instant extra profit!!!!
After this discovery I immediately went back to buying directly from my Chinese supplier and except for an occasional controller, the failures have disappeared. I have not broken apart one of the SSRs that work, but based on the difference in performance it's obvious that there is a internal difference in these parts.
Did you use this instructable in your classroom? Add a Teacher Note to share how you incorporated it into your lesson. If you have been using your SSR with no issues for a while then most likely you have a good one. The best solution is to 'assume' that the part you buy has been re-labeled and buy a SSR with higher current rating than you need. The cost is not much higher and you still purchase a quality part for far less than a SSR you would buy from a USA name brand supplier.
Or you could just buy a name brand like Crydom, but with counterfeits so common these days how do you know if your eBay sourced Crydom SSR is real or counterfeit?
You don't! The best solution if you are buying one that has to work is to "bite the bullet" and buy your SSR from a licensed distributor like digikey. Question 1 year ago on Introduction. It was passing 11A 40A rated part but at v v rated part. Failed in the on state. I'll have to crack it open to see what's in there.
Answer 1 year ago. I'm not familiar with the brand so I looked them up. At least they are a good looking part Since my article I discovered an easier way to judge the part's current rating. I found out that the lower current TRIACs are mounted with screws while the higher current parts are sweat soldered to the base. The higher current parts need the sweat solder bond you can't get with thermal compound. It would be worth looking for a threaded hole on the back side of your failed SSR before breaking it apart.
I agree that it's relatively simple and inexpensive to design your own SSR's from triacs or SCR's; however, there are a number of appnotes relevant to addressing component selection and protection that are perhaps better than blindly grabbing a schematic from GIS.
Lastly, if you do decide to roll your own, be aware that there are counterfeit triacs on ebay too, and they'll give you just as much trouble, if not more. Reply 5 years ago on Introduction. Thanks for the great references.
One of my motivations for "rolling my own" is I can build the SSR directly onto the heatsinks I'm using, eliminating one thermal resistance layer. In the mean time I did find one brand that performs as advertised.
Thanks for the heads-up I have bought some of these relays, but I think building my own would assure me of the desired rating. Here is one example. The amount of current that project will be able to switch will be limited to the watts dissipated by the TRIAC - about 1. Assuming the SSR itself does not fail, all the components inside will be cooking at whatever temperature the housing settles to. My "best guess" is this one is good for up to 5 Amps based on the housing.
A larger housing is better, a finned heat sink is even better and a fan cooled finned heat sink is best - all depends on how much heat you generate! Thanks for finding this. I was building an automation setup and was thinking of using the foteks. On my budget, I'll buy the higher rated ones. Thanks again. I believe that the counterfeiters have taken advantage of and are profiting from their popularity. One point I made is even the counterfeit SSRs were well built.
And based on what I found I would not have a problem using them if I had to, I would just use a higher current SSR than my project called for. By Tom Hargrave www. More by the author:. Dec Update A lot has happened since writing this article in early So, these days we only buy directly from a few Chinese manufactureres or trusted importers. Yes we still buy Chinese manufactured SSRs.
The counterfeit issue we all deal with is caused by greedy Americans, including greedy Chinese Americans, willing to make a quick profit at anyone's expense. China is just one major manufacturer willing to make whatever we are willing to sell.
We started buying only 45 Amp rated SSRs and have been for a while, and the reason is simple. Flipping the SSR over to verify the screw hole is not there is quick assurance that we really received what we paid for. The Original Article Not too long ago we had a serious warranty issue with some of the controllers we manufacture.
Add Teacher Note. What should you do if you are designing your own controller? Tom - www. Did you make this project? Share it with us! I Made It! Cryptic Wall Clock by tomatoskins in Clocks. Large Motors Class 14, Enrolled. Answer Upvote. Tom Hargrave nedfunnell Answer 1 year ago. Reply Upvote. Just got a "Fotek" from eBay.. ElFantastic0 5 years ago on Introduction. Tom Hargrave acheide Reply 5 years ago on Introduction. Tom Hargrave 69fordf Reply 5 years ago on Introduction.
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