Ebay PIDs

[lustreking]

I'm in the planning process of a standalone electric HERMS heat exchanger. The only thing that I haven't nailed down yet is the controller for it.

I know that I need a PID, and I've seen several on Ebay for less than $45 shipped, including the thermocouple.

Here :
Here's one
Here's another
One more

Does anyone with knowledge of PIDs have any recommendations? This will only be used for the heat exchanger, so I don't need manual control (which I don't think these have).

 

[The Pol]

Those look good... two major points to consider with them and any application...

You already know you dont need manual mode (that is one point)
You need to make sure they have an SSR output to drive an SSR (looks like these do)

Looks like you know what you are doing.

 

[lschiavo]

I used an Auber SYL. All the ones you listed look similar. But I have never used any.

I think I paid about $50 for my controller and an extra $20 for the probe. I would make sure the probe included is going to work for your build. Also, the Auber is capable of using many styles of probes. Looks like the ones listed may only be K type?

 

[The Pol]

FWIW, I used the K type thermocouple on mine... it was $6 and worked very well.

I used the SYL 2352 as well, but only because I wanted manual mode.

 

[CodeRage]

There are quite a few people here who have used the TET612. Not sure what their experiences are, a quick search on it may help you.

I would recommend you stay away from the sure electronics one. The manual is awful. I had to find the legit ktc controller they ripped off and use it's manual. Even then it did strange things and their support sucked.

I bought 3 of the Sures, I use 2 as temp read outs and thats it. I don't trust them for controlling anything.

+1 on the Auber SYL, it's a good product and their support is good too. If you ask me it isn't worth the $10 in savings.

The thermo couples those come with are not suitable for submersion either. You can use JB weld to seal the threaded sheath to the probe and use a wing nut to hold it in place. I think this came from Pol's Bling Bling Herms build.

I would ditch the K thermocouple for an RTD too. Better accuracy.

 

[passedpawn]

I had some gross errors using thermocouples with the Auber PID. I did a bunch of simple experiments and the result was the PID is not very accurate with thermocouples. I would recommend thermistors or RTDs.

To be fair, the PID is probably accurate if it does not change temperature during the brew session. I always brew outdoors and the temperature can vary widely. Additionally, my control panel can warm up due to heat transfer from the heat sinks. It is really easy to reproduce this problem by simply blowing hot air on the pid (i.e., hair dryer). Mine would swing more than 10 deg F. The "cold junction" which is in the PID is the culprit. But don't believe me... call Auber and they will corroborate.

 

[CodeRage]

I had some gross errors using thermocouples with the Auber PID. I did a bunch of simple experiments and the result was the PID is not very accurate with thermocouples. I would recommend thermistors or RTDs.

To be fair, the PID is probably accurate if it does not change temperature during the brew session. I always brew outdoors and the temperature can vary widely. Additionally, my control panel can warm up due to heat transfer from the heat sinks. It is really easy to reproduce this problem by simply blowing hot air on the pid (i.e., hair dryer). Mine would swing more than 10 deg F. The "cold junction" which is in the PID is the culprit. But don't believe me... call Auber and they will corroborate.

If you look at the back side of the controller, there is a little hole and in it looks like a glass bead diode. That would be the cold junction probe. I discovered the same thing when I put my finger over it

General FYI-
Just about any thermocouple sensor will have a cold junction so it isn't just an auber thing. Typically the probe should be immersed in ice water as a reference for best accuracy. That isn't always feasible so room temp is some times used.

 

[lustreking]

Thanks for the replies everyone. I'm trying to do this project as inexpensively as possible, but it looks like I may not want to go cheap on the PID.

I do have a love ts-13010 that controls my fermentation fridge. How would that work in a HEX until I can budget the money for a "proper pid and temperature probe?"

I assume that the temperature output of the HEX would over/undershoot more than with a PID, but would it cause any problems? It won't be in a HLT, it will be a small (2 gallon or less) container, which might compound the swings, or no?

I plan on using a 1500W element, so the element should be ok to use with the love, which is rated at 16 amps.

 

[CodeRage]

I am guessing you are planning to use a HERMs?

With that controller I think you are limited to hysteresis type controls:
Depends on how the system is set up. If you put the probe on the output of the HEX you may run into problems with the output cycling up and down a few to several degrees.

If you put the probe into the Hex water it will buffer that sum and you wont see as drastic temp swings of the output. but the lows and highs will be a little longer due to the volume.

Since the volume of water in the hex will be small and depending on your hex length and flow rate a PID would be a good choice.

 

[LayMeister]

Bought one from "One More" after I saw your note. Had the cheapest international shipping and a good rating as a seller. Will let you now how it goes.

Paul

 

[DavidP]

The "TET 612" model sold by Sure works well enough for what you pay for it, but I've found that no matter how they're configured they always overshoot. I've had much better luck with the accuracy of Auber controllers.

For what it's worth my cheapo PIDs are labeled "SET 620" but they're all the same underneath.

 

[andynaj]

tET 612, i use this controler on my glassblowing kiln hooked up to a 50 amp ssr and a sending unit with a k type thermolcouple, a little over kill for a fridge i know, but as far as set point controllers go i like this one, its cheap, easy to go up or down as need, the only draw back it is the manual sucks and took me a minute to figure out the ssr, i usually use mercury relays or mechanical contactors

 

[tacocat]

I haven't had the best of luck with ebay pid temp controllers. I use one in a completely unrelated application just to monitor temperatures that range from about 600° F to 1100° F, and the device is terribly unreliable. It worked great for about 4-5 months, and then decided to work intermittently. Now it doesn't work more than it does. Although, it is also in an environment subject to vibrations, fair temperature changes, etc.

 

[LayMeister]

Showed up today. Only took 10 days. Works great so far.

Bought one from "One More" after I saw your note. Had the cheapest international shipping and a good rating as a seller. Will let you now how it goes.

Paul

 

[MrH]

I know you already got yours and it's working, but for others who may read this I thought I'd just say that I've got two TET612s and one of them reads 15-20F high when using a RTD sensor. It works with the K thermocouple that it came with. I've tested the same sensor with three other PIDs and all three read ok. I got it on ebay and I'm unable to return it. I just ordered an Auber SYL-2352 to replace it, and I feel better dealing directly with a vendor that stands behind their product.

Just my .02...

MrH

 

[Dwain]

...I feel better dealing directly with a vendor that stands behind their product.

Yeah, I've bought 3 off of eBay at one time. Of the 3 PID's I've bought, none of them worked. I used K type thermocouples with all 3. I had an IE look at my set up, he said it was installed correctly, they just didn't work. By the way, each one had a different problem. Luck - Dwain