Will this work? heatsink for 40amp SSR

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Bean

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I'm in the sourcing phase of converting from propane to electric. I'm building a 50amp HERMS system using MRG 40amp SSR's, MRG-1 D4825.

I happened upon several Foxconn 344498-001 rev B heatsinks, looks like this. It's approximately 3x3.5x2.5. My question is, will these provide the necessary cooling without a fan? These are larger than the typical heatsink assigned to 40amp SSR's but without an understanding on how fin structure helps move hot air out and cool air in I'm concerned without a forced air solution the compact fin structure of the computer heat sync would cause the SSR to fail.

I have considered winging it.. I mean, SSR's aren't the most expensive thing but I would prefer not having to rip apart a freshly built system after only a brew or two, or worse lose a beer because of it.
 
That should work fine If not better than the crappy heat sinks the SSRs come with. Copper is muy bueno. Put the fins so that convection can circulate air through them. I've used several PC heat sinks on SSRs. Just have to Drill and tap them.
 
I'm in the sourcing phase of converting from propane to electric. I'm building a 50amp HERMS system using MRG 40amp SSR's, MRG-1 D4825.

...
MGR-1 D4825's are 25A SSR's. The 40A part is MGR-1 D4840.

Brew on :mug:
 
oops... well i guess im using the 25s until they burn up.. sigh. unless the consensus is to purchase the 40s now.

im absolutely going to mount the heatsink outside of the enclosure.
 
Here's how I mounted my heat sink - an aluminum CPU heat sink from a Dell computer. I've not brewed with my new systems, as I'm still waiting for a couple items to be delivered. I'm not using a fan yet, but will monitor the fin temp during a brew to decide if it's necessary.

I cut a hole in the enclosure that is the same size as the 40A SSR. The Heat sink is larger, and I JB welded the heat-sink to the enclosure. The SSR is screwed directly to the heat-sink.

I've tested the system by heating water, boiling water, changing power output of the SSR/Heat element. But when I tested, it was very cold in my garage (about 30F). I don't yet have a real-world test to know if the heat-sink is up to snuff. But, I don't think it'll be a problem. I might take an extra temp probe and somehow stick it to the fins to graph temperature, not that would be real accurate to the SSR temp.....

IMG_20171209_134839.jpg
IMG_20171215_094250.jpg
 
im going to give it a shot and see what happens. I guess I was a little reserved as most of the panel pictures i've seen here either use the stock ones that come with it or the "oversized" one kal put out. I didn't know if it was a lack of experimentation from the community and simply went with something which is known to work or if the larger fin spacing was needed. This is the first time i've played with SSR's so I don't have an understanding of how hot they will get.

I have seen some add a sticky on wire temp sensor to their fins. But, like you said, it might not be that accurate.
 
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I've always assumed (Maybe wrongly....) that an SSR will give off about 1 Watt per amp.
 
oops... well i guess im using the 25s until they burn up.. sigh. unless the consensus is to purchase the 40s now.

im absolutely going to mount the heatsink outside of the enclosure.
Ive been using 25a rated ssrs for 22-23a elements for years now... They are rated for up to 25a which means they are intended by the manufacturer for up to 25a load, Your fine. Theres a theory/ assumption? floating around here that 40a ssrs will run cooler than 25a with the same load which I dont believe anyone has actually tested.
 
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This is the first time i've played with SSR's so I don't have an understanding of how hot they will get.

They don't get hot at all when you mount them to a heat sink :)
...Seriously, one of those for each SSR and they'll be cool as a cucumber
Brew on
 
Ive been using 25a rated ssrs for 22-23a elements for years now... They are rated for up to 25a which means they are intended by the manufacturer for up to 25a load, Your fine. Theres a theory/ assumption? floating around here that 40a ssrs will run cooler than 25a with the same load which I dont believe anyone has actually tested.

we'll see how deep I dive into this, perhaps i'll be the one to test if there is a temp difference between the two. I would assume not as well but who knows.
 
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