cheapo Ebay SSRs

Yep, another SSR thread. A few months ago I got a cheapo FOTEK 40A relay off of Ebay for around $5 USD. I don't have a heatsink, so I can't put it on a large load to test it. I just recently scored a free SSR-240D50 sample and saw that they retail for around $80 (no wonder TE would only give me one, when I requested two.) So how well do the cheap Ebay SSRs hold up on moderate loads? I've read about some people having their SSRs from Ebay fail controlling loads considerably below their maximum ratings.

Does it get hot…? If not, you’re probably OK. There’s not an awful lot inside an SSR, $80 for a couple of MOSFETs seems a bit much to me.

If you’re paranoid you can apply the eBay rule of thumb and run it at half load.

Right now I'm just running some low current resistive loads, so no issues with heat. I'm just curious of what people's experiences are with the ones commonly bought off of Ebay.

That is a huge generalization. It's not like "ebay" is a brand and all SSR's on ebay are the same.

I think that what needs to be taken into account here is that "ebay" is a logical dumping ground for excess inventories of good products (cheap) as well as a dumping ground for manufacturing "rejects" that "work" but did not meet manufacturing specifications. (I would not be surprised if a certain amount of "customer returns" end up on ebay.)

So, I would not go so far as to say that ebay SSR purchases must be inferior somehow... you just need to "consider" what your possible sources are.

Personally, I prefer to buy things like SSR's from places like MPJA.com where yuu can get a "surplus" relay at a good price. 20A, 480VDC Solid State Relay | MPJA.COM

pwillard:
So, I would not go so far as to say that ebay SSR purchases must be inferior somehow... you just need to "consider" what your possible sources are.

I've bought many hundreds of electronic parts on eBay and never had a single one that looked second hand or failed to work.

Some of the parts I've bought get a bit hot when you run them at full power but that applies to non-eBay stuff as well. For things like power supplies and high power LEDs I usually buy more watts than I need and underpower them a bit. They've always worked reliably that way.

I prefer sellers who make an obvious effort in their item descriptions and I never go for the absolute cheapest prices unless it's a common item with many different sellers selling it.

Support? I bought an OLED screen which didn't work as described. I emailed for more info and ended up talking to the actual engineer who designs them. He sorted me out, no problem. There's quite a few sellers on eBay who also seem to be the manufacturers.