"Fotek" SSRs on eBay

[yveei]

So I didn't heed the advice I'd read online about knock off SSRs and decided to buy a Fotek SSR for my electric setup.

And on the second use I smelt an odd smell and thought I saw a wisp of smoke.
Sure enough when I took my controller apart, there was my SSR...

Also to note: this was rated for 40A and I only ever draw about 11 amps as I have a 2750 watt element.

 

[tdiowa]

This ought to be a sticky

 

[doug293cz]

Not sure you can blame this one on "Fotek." That burn pattern is almost always due to a loose connection at the terminal that is burned. Connections that are not tight have a much higher than desired resistance, and this causes the connection to heat up. An internal fail in the SSR is more likely to melt/discolor the central part of the SSR.

Brew on

 

[yveei]

Not sure you can blame this one on "Fotek." That burn pattern is almost always due to a loose connection at the terminal that is burned. Connections that are not tight have a much higher than desired resistance, and this causes the connection to heat up. An internal fail in the SSR is more likely to melt/discolor the central part of the SSR.

Brew on

Good to know, but I'm so sure I had the terminals good and tight.
The terminal is loose in the pic by the way, where I tried (unsuccessfully) to remove the connection after the burn.

I will indeed brew on though

 

[RufusBrewer]

I am about as cheap of an SOB as the next guy. I like to save a buck or two when I can. Some things are not worth hoping they are good enough. I would hate to have a brew day go bad because I tried to save a $3-$4.

Maybe this is an installation issue, maybe it is a part failure. Perhaps if I had confidence that I bought a properly rated and good quality part in the first place, I would not be thinking about what went wrong in the second place.

I would chalk it up as poor installation, replace the part and do proper maintenance going forward.

Also, I use over rated parts. I woud not use a 25 amp SSR in a 20-25 amp application. I would get a 40 amp model and a heatsink that matches a 40 amp application.

I am curious, how does a termination get loose and cause problems? A power panel is not used in a in a high vibration environment. Unless you never tightened down the termination in the first place. I guess regular into a power panel and verifying proper torque on all connections is in order.

 

[stevehaun]

You can find quality SSRs, eg, Crydom, at reasonable prices on Ebay.

 

[doug293cz]

...

I am curious, how does a termination get loose and cause problems? A power panel is not used in a in a high vibration environment. Unless you never tightened down the termination in the first place. I guess regular into a power panel and verifying proper torque on all connections is in order.

The thermal expansion/contraction caused by the heat up and cool down inside the enclosure can cause screw connections to loosen over time. Routine maintenance of a control panel should include torque checks on all screw terminations.

Brew on

 

[augiedoggy]

I am about as cheap of an SOB as the next guy. I like to save a buck or two when I can. Some things are not worth hoping they are good enough. I would hate to have a brew day go bad because I tried to save a $3-$4.

Maybe this is an installation issue, maybe it is a part failure. Perhaps if I had confidence that I bought a properly rated and good quality part in the first place, I would not be thinking about what went wrong in the second place.

I would chalk it up as poor installation, replace the part and do proper maintenance going forward.

Also, I use over rated parts. I woud not use a 25 amp SSR in a 20-25 amp application. I would get a 40 amp model and a heatsink that matches a 40 amp application.

I am curious, how does a termination get loose and cause problems? A power panel is not used in a in a high vibration environment. Unless you never tightened down the termination in the first place. I guess regular into a power panel and verifying proper torque on all connections is in order.

I have to disagree on needing a 40 amp rated ssr for a 20a load... I do not use 30a rated wiring and wall outlets for my 15 amp circuits for the same reasons... someone else designed and rated these thing for a reason. I use the correctly rated wires for the same reasons as well as cost savings. I use like 12 ssr in my 3bbl brewing system every week for hours on end and never a failure. if the price is right and they are the same size its better to erro on the larger side but its not necessary with quality components.

That said, if I was using cheap questionable components, its always better to go with higher rated components. The only difference between a 20a rated fotek clone and a 40a fotek clone has been shown to often be the sticker. Seriously there are multiple blogs and videos showing the same 10a rated internal triacs are used in some of these fakes.

 

[RufusBrewer]

In my mind, the cost of upgrading, is a consideration. Looking at Auber Instruments, 25 amp SSR = $10.00, 40 amp = $16.50. $6.50 is worth the extra safety margin. Considering solid state devices failure modes, 50% - 100% is not overkill and appropriate. IMO, a wise investment in reliability.

I would hate to have a brew day get ruined due to cutting the safety margin to save $6.50. Pay the pain at the front end and save the sorrow on the back end.

When you are talking cable gauge, the reasonable safety factor is already built into the recommended current vs gauge size guidlines. Under normal circumstances, you could "get away" with smaller wiring. But not a wise choice, plan/build for worse case failures. IMO Another example the savings do not justify the reduction of reliability. IOW follow the recognized current vs wire size standards and enjoy your brew day.

 

[augiedoggy]

In my mind, the cost of upgrading, is a consideration. Looking at Auber Instruments, 25 amp SSR = $10.00, 40 amp = $16.50. $6.50 is worth the extra safety margin. Considering solid state devices failure modes, 50% - 100% is not overkill and appropriate. IMO, a wise investment in reliability.

I would hate to have a brew day get ruined due to cutting the safety margin to save $6.50. Pay the pain at the front end and save the sorrow on the back end.

When you are talking cable gauge, the reasonable safety factor is already built into the recommended current vs gauge size guidelines. Under normal circumstances, you could "get away" with smaller wiring. But not a wise choice, plan/build for worse case failures. IMO Another example the savings do not justify the reduction of reliability. IOW follow the recognized current vs wire size standards and enjoy your brew day.

I do understand that point of view. but it should not be a reduction in reliability if in fact the correct quality component is used with the correct installation and heat sink. $16.50 is more than 50% more cost for a single component of a build. In my case I believe I used 25a crydom ssrs.. There are 10 of them in my panel for heating element control alone. The cost difference between a 25 amp crydom and 40a crydom is more than $6 and due to the fact that the crydom ssr is a more relable component than the much cheaper MGR made ssr auber uses (which are good quality btw) I guess you could say I already "payed the pain" at the front end by finding a better component for less. Ive heard it stated that a 40a ssr will run much cooler than a 25a but I actually had both side by side in one of my first control panels and I couldnt tell any difference in how hot they each got to be honest. I'm sure in some designs it has to be true however.

I work on electromechanical machinery for a living and Ive seen different manufacturers take different approaches when it comes to this sort of thing. The japanese for example (whom build some very reliable equipment) typically do not in my experience over engineer or use overrated components in their designs very often. They typically just try to design it to be the most efficient and profitable design. Most professionally built equipment accounts for additional manufacturing cost vs failure/relability concerns... If it really was a worthwhile concern it would just seem you would see oversized relays used in these items and its very rarely the case yet I couldnt tell you the last time I had to replace one of the ssrs in the equipment I service every day.... PIDs, yes Ive had to replace 2 this year already.