Need PID Help -Auber Instruments 2362

The RIMS project is complete. We made a custom cart from 1" square steel. Got a 20 gal Blinchmann Pot, a Therminator, march pump, water filter, made a heat stick with a 2000w 120v water heater element, etc....
Everything is working great except for a couple PID/RTD issues. The RTD is reading about 15-20 degrees lower than the actual water temperature. For example the thermometer on the brew pot will read 160 and the PID will be about around 140 degrees. I went into the PID menu and set the input to the PT100 sensor. I have attached a pic of the RTD sensor in our heat stick. I'm wondering if the RTD is inserted into the heat stick far enough? I have checked the accuracy of the brew pot thermometer. It's dead on. Is there a way to calibrate the RTD? Is there a different setting I need to have it on possibly?
The other issue is for example: we set the temp on the PID at 140 degrees. The water heats up to 140 and the keeps going past the set temp. It goes at least 5 degrees past if not more. ow do I change the setting for this? I've tried reading the booklet that came with it.....I think it is in Hungarian...thanks fellas.

http://i957.photobucket.com/albums/ae51/greenshane74/RTD.jpg

Auber Instruments 2362 PID Controller
PT100-L50NPT RTD Sensor

Not familiar with your model #, most people use the SYL 2352... but does yours have autotune? That should help you get the PID functions programmed.

Actually, I think most opt for the 2362 since they added a manual mode as it's now cheaper than the 2352 for the same features.

buckeyebrewer - you need to go into the setup and set the offset for your RTD. You also need to run an auto-tune cycle to allow the PID to learn your system. Here's a copy of the notes I recently posted in my CB-20 build thread on the 2362:

The default settings are almost perfect. Only the Hysteresis Band needs adjusting from the default of 3 deg down to 1. Start by going into setup mode by pressing SET, entering 0089 and SET again. Hit the down arrow until HY is displayed. Hit SET, change the default value of 3 to 1, and hit SET again. Down arrow to END and hit SET to exit setup mode.

Fill the kettle with about 4 gallons of water. Press the Up arrow to set an SV of 150 deg. Press and hold > until the AT/M light starts blinking. This is the auto-tune mode. The PID will heat up and cool the kettle several times while it learns the response times of your system. This will take a while and PV WILL exceed SV. Don't worry and just let it do its thing. When auto-tune is finished, the AT/M light will go out. All learned settings are permanently saved so there's no need to auto-tune again unless you alter the system (new heater element, bigger kettle, etc.)

The PID is ready to use at this point. Simply enter your desired SV temp and the PID will do its best to reach and hold that temp. PV is of course always displaying the current temp reading from the thermocouple. For the boil, you'll probably want to switch the PID to manual mode. Press and hold SET until the AT/M light turns on. SV switches to displaying % output of the element. Simply use up/down to set your desired % output.

The remaining lights are all informational. AL1 and AL2 lights can be ignored. You can set temp ranges that turn them on/off via setup mode, but there's no real use for them. I may someday put buzzers on my AL1 / AL2 relays so the PID can alarm me as strike temps approach, etc. The Output light tells you when the SSR is being energized and power is flowing to the element.

If after use you notice the PV temp is off from a thermometer reading (read the water temp flowing into the mash tun - not directly in the kettle), you can adjust the thermocouple offset via setup. Go back into setup mode, arrow down to PSb, and set it to +/- the number of degrees the PV reading is off.

I did the auto tune mode but the rtd is still reading 30 degrees below what the actual water temp is, is there a way to manually calibrate the pt100 rtd?
Thanks for your help!

buckeyebrewer said:

I did the auto tune mode but the rtd is still reading 30 degrees below what the actual water temp is, is there a way to manually calibrate the pt100 rtd?
Thanks for your help!

Click to expand...

Put the probe into a cup with a slurry of crushed ice and water. Let it rest for a minute or two until the temps stabilize.

Write down the temperature it is reading, take subtract that number from 32. So if you read 40deg then 32-40=-8.
Find the Pb value in the configs menu and make it match the number you came up with. Then you're calibrated

I think I've got it now! I set the Pb value to 30 (since it was off by 30 degrees) and it seems to be right on the money now. I'm just hoping it will stay on the money through all temp ranges.
Thanks for the help!

The probe being off by 30 is worrisome. In my experience probes only need to be adjusted by 5 or less degrees. But hey if it's accurate vs. a thermometer ride with it.

DavidP said:

The probe being off by 30 is worrisome. In my experience probes only need to be adjusted by 5 or less degrees. But hey if it's accurate vs. a thermometer ride with it.

Click to expand...

Yeah, that is a bit much. Ice water doesn't need to be calibrated.

Put your regular thermo in some ice water and see if it reads 32deg.

The Blinchmann thermometer is reading 158 and the RTD is reading 156. Very close.....we may need to adjust a couple more degrees but it is working. Thanks for all of the quick support.

I am unfamiliar with the RTD you are using, however I do know for a fact that you will obtain the most accurate temperature reading results by calibrating an RTD with a "5 up 5 down" method. This method eliminates error and is a standard in instrumentation calibration as far as I know in my own experience with instrumentation.

Hope this helps and good luck.

CodeRage said:

Yeah, that is a bit much. Ice water doesn't need to be calibrated.

Put your regular thermo in some ice water and see if it reads 32deg.

Click to expand...

I've got the 2362 and put the rt100 in some ice water. I'm recirculating and the probe is mounted on a tee off the pump. I got a reading of 32F and verified with a digital kitchen thermo and a IR thermometer. Both read 32F.

I heated the water up and the probe read 160F. My other two thermometers were both reading 170F, and the spread lasted until about 209/200F.

So what's that all about?

brewfreeordie said:

I've got the 2362 and put the rt100 in some ice water. I'm recirculating and the probe is mounted on a tee off the pump. I got a reading of 32F and verified with a digital kitchen thermo and a IR thermometer. Both read 32F.

I heated the water up and the probe read 160F. My other two thermometers were both reading 170F, and the spread lasted until about 209/200F.

So what's that all about?

Click to expand...

I too am having issues where my probe and thermometer seem to correlate at lower temps, but differ at higher temps, and then correlate again at boiling. I just found this thread and plan to mess with some settings mentioned here, but seems odd that temps match low and high but not midrange ~150*F (discovered that I've been mashing 5-7*F higher than intended)