Need some help planning my "budget RIMS"

[Geordan]

Hey folks, I'm putting together a RIMS on a shoestring budget, and I'm hoping to get some advice/feedback from everyone here. I'm going to itemize my questions for clarity:

1) Since I'm working on a REALLY strict budget, a true Auber PID's out of the question. I've been counting on using a REX C-100 PID from eBay, which some folks I know have used with success. However, I can't tell if:
a) They're actually 120V happy; they list 100-240V as compatible, but I found a page via Google that suggested at 110V they returned inaccurate results
b) They can actually use an RTD probe; some of the documentation online says they can, others say they can't. Anyone have experience with this?

2) Following the RTD question: I understand that RTDs are preferable to Type K tcs, since RTDs are more accurate and less prone to "drift." Type K's are definitely cheaper -- is the "drift" something that's permanent, or can it be helped by recalibrating occasionally? My concern is mostly that the I don't want to get the REX C-100 PID and waste money on an RTD I can use, if a Type K tc is a safe bet

I'm working of a PJ diagram for a simple 120V 20A RIMS build; it's as simple as a RIMS can get, really. Hoping someone can offer advice on this. Thanks!

 

[kenh]

There is nothing wrong with a K type thermocouple - in the homebrew environment they don't drift.

Stay away from the REX C-100 controller. Buy a Auber 2352 or a MYPIN TA4-SSR controller. Your are looking at less than $10.00 difference, so why take a chance!

 

[Geordan]

Thanks Ken. Do you mind if I ask why you said to avoid the REX C-100? I can get it for around $25 shipped to Canada with an SSR, whereas the Auber PID is $46+shipping+duty+conversion (coming to closer $70). Have you had a bad experience with the REX C-100? Anyone else familiar with these "Budget" PIDs?

 

[nebulous]

while i havent used the REX C-100 the main reason not to get the REX-c100 is because its got a relay out rather then an SSR out. however the real value in a PID are the autotuning and fuzzy logic, which the REX PIDs are not great at. these features are what help the PID to "learn" your set up.
for about 10$ more you can get the TD4-SNR with an SSR and free shipping. the TD and TA series of pids from Mypin have fuzzy logic with the difference between the two being the TDs have a manual mode where as the TA does not.

 

[kenh]

Thanks Ken. Do you mind if I ask why you said to avoid the REX C-100? I can get it for around $25 shipped to Canada with an SSR, whereas the Auber PID is $46+shipping+duty+conversion (coming to closer $70). Have you had a bad experience with the REX C-100? Anyone else familiar with these "Budget" PIDs?

The REX C-100 has a relay out only and you also need to buy a power supply & do even more wiring. It does not annoy me so much that it has relay out only, but they lie about it. It's like they just threw a bunch of words in their listing just to sell their product!

 

[Geordan]

Not sure what you mean by relay only -- my understanding is that there's a relay version and an SSR version, and the trick is to confirm with the seller than it's the SSR flavour. A member of my local group has a couple of REX PIDs in an all electric rig that he's using with SSRs. When you say you need a power supply, do you mean for the relay, or does the REX PID require some sort of additional power supply I've overlooked?

 

[Geordan]

...
for about 10$ more you can get the TD4-SNR with an SSR and free shipping. ...

Would you mind sharing a link for this unit if you've got it? I'm not finding many results in a quick eBay search, and none bundled with an SSR, though that could be my poor search terms.

 

[kenh]

Not sure what you mean by relay only -- my understanding is that there's a relay version and an SSR version, and the trick is to confirm with the seller than it's the SSR flavour. A member of my local group has a couple of REX PIDs in an all electric rig that he's using with SSRs. When you say you need a power supply, do you mean for the relay, or does the REX PID require some sort of additional power supply I've overlooked?

I bought two off eBay and both were supposed to be the SSR version, but when I got them they were not. One shipped from China and one shipped from somewhere in the States.

And yes, I mean a outside 12V power supply. You have to run one side of the power supply to the PID and then to the SSR. The other side of the power supply runs straight to the SSR. Splicing the wall plug power supply wires is a real pain because they are tiny and break before you know it.

 

[nebulous]

Would you mind sharing a link for this unit if you've got it? I'm not finding many results in a quick eBay search, and none bundled with an SSR, though that could be my poor search terms.

http://m.ebay.com/itm/110880595387?nav=SEARCH&sbk=1

That's with a 25A ssr the seller also has then with 40A

Edit: you will need to get a temp probe but one without a thermowell is only a few bucks

 

[Geordan]

Thanks nebulous, that's a big help. Unfortunately, it looks like the reputable-looking US sellers don't ship to Canada (or charge $79 to do it). Is anyone able to tell what the difference between the PID you linked, which seems to the the "TD4", and this one (http://www.amazon.ca/dp/B005NGL4KG/?tag=skimlinks_replacement-20), which is the "TA4"?

 

[kenh]

http://m.ebay.com/itm/110880595387?nav=SEARCH&sbk=1

That's with a 25A ssr the seller also has then with 40A

Edit: you will need to get a temp probe but one without a thermowell is only a few bucks

MYPIN works great - I run one now. Mine's a MYPIN TA4-SSR.

 

[dyqik]

Looking at the circuit diagrams on the side of the units in the photos on the the two eBay pages, and assuming that they are for the correct item, it looks like the TD4 only has one alarm output, while the TA4 has two alarm outputs, one of which can also power an second SSR.

 

[Geordan]

Looking at the circuit diagrams on the side of the units in the photos on the the two eBay pages, and assuming that they are for the correct item, it looks like the TD4 only has one alarm output, while the TA4 has two alarm outputs, one of which can also power an second SSR.

That's a huge help, thanks for clarifying that. Sounds like either of the two will do just fine for a simple rims. I assume the Alarms are used to wire up to a speaker of some sort, and are programmed to sound when targets are reached, etc? Can anyone see a situation in which you may use two alarms and/or two SSRs from the same PID? I'll confess that I don't know enough about PIDs to see a functional difference for brewing applications.

 

[kenh]

A TA4-SSR has two SSR outputs and one relay output. The relay is in parallel with the second SSR output.

I use mine to run my RIMS and I was thinking of wiring a high limit alarm through the relay & setting the alarm temperature to 160 F. This way if my RIMS temperature goes crazy I have a chance to pull the plug before the enzymes in my mash are denatured.

There is a table on the net somewhere that shows the different models, I'll look for it again & if I find it I'll post a link.

 

[dyqik]

That's a huge help, thanks for clarifying that. Sounds like either of the two will do just fine for a simple rims. I assume the Alarms are used to wire up to a speaker of some sort, and are programmed to sound when targets are reached, etc? Can anyone see a situation in which you may use two alarms and/or two SSRs from the same PID? I'll confess that I don't know enough about PIDs to see a functional difference for brewing applications.

You can use the alarms in a couple of ways - these are switches that close when a specific threshold temperature is reached. You use one for sounding a buzzer to tell you when you've reached strike temp or mash out temps for example, or you can use them as alternative set points with simple temperature controller type behaviour.

One common use in the single boiler espresso machine world is to set an alarm point at the steaming temperature, and then use a manual switch to go from the PID controlled "brew" temperature to the simply controlled "steaming" temperature (the switch switches the SSR input from the PID output to the Alarm output). One use that I can think of in a RIMS system is to use a similar system with an alarm to control the mash out/sparge temperature with out having to fiddle with the mash rest set point temperature.