allenb wrote:

Hi HC,

Sorry for the slow response but the weekend is a slow response time here at HRO due to all the back yard activities!

Jim will have to answer the lead time question on TC4C. I think he's been out of town for a few days so give him a little time.

SSR is fine and the 3-32 will work with the TC4C's output as is.

Always a good idea to use something for a heatsink to bolt on to the SSR or, if using a sheetmetal enclosure just attaching to it will work and use some conducting compound. If a plastic enclosure like you've posted then mount to it's exterior with a slab of metal or surplus heat sink of your choosing.

On thermocouples. Buy the cheapie general purpose ungrounded, unsheathed basic TC:

http://www.instru...ermocouple

They state only good for up to 260 C but I've used them up to 650 F with no problems. You want instant response and to not have to wait for a metal sheath to catch up a minute later. You can get creative with mounting with a screw and washer to hold it in place. Using sheathed, grounded thermocouples can create grounding issues that are very tough to pin down. Just don't have the bead touch other metal components.

On measuring ET (you want to measure the whole ET and not just maximum ET! I hate the abbreviation MET! Sorry about that.


Yes, find a neat place to stick the cheapie thermocouple in the area just prior to the roast chamber. use a sheet metal screw and washer if needed to keep it from wandering. Just be careful to not screw into any nichrome or wires! Your reading will not be a perfect average of the total air stream hitting the beans but will be plenty good enough for a reference as long as it stays put.

For fan control, Jim or others can hopefully lend a hand with needed phase control or other means of having Roastlogger and TC4C control it.

Stay tuned and more to follow from our popper and TC4C wizes.

Welcome to HRO!

Allen

happycat wrote:

Could i use this ssr? It is way cheaper than others prob due to the packaging difference. Is 3v-32v dc input for control ok? Again... Is that programmable?

http://www.digike...-ND/753399

happycat wrote:

This might be a good thermocouple. With a plug... Could unplug box from roaster when not in use or just remove connector... Shame to pay for connectors won't be using but would be cheaper to buy everything here vs some from omega (shipping)

http://www.digike...-ND/415777

clif123 wrote:

Hey HC,

I'm just starting a new hot popper roaster project myself and also new to this forum. It is probably too late for you, but I found some good prices on parts that I hope work for this project. I got a $5 stainless probe K thermocouple off of Amazon (search for: "amico k type 5cm long probe thermocouple") and I was able to get some overkill 50A 240VAC SSRs for $7 off of eBay. I found that the quality used ones were safer than gambling on the new cheap knock-offs. I had the parts for doing the thermocouple sensor logic myself but after I saw the TC4, I had to bite. I can't wait to get my hands on it.

clif123 wrote:

HC,

Curious if you have any update on the turnaround of your TC4. I'm waiting to hear back about that also. I placed my order back in early May but have not heard anything. Is this normal?