PID/RTD sensor issues

[R2Brew2]

Need a little help here. My PID (a Mypin TD4) had been working just fine. All of the sudden, I'm not getting any temperature reading. Or more precisely, the PID reads UUUU, which, per the manual, means "The input signal exeed the measured HI range." It's the same error I get when the cable isn't plugged in at all, only now it is. Nothing is loose, everything seems to be making full contact. Is it possible that these cables or the connectors can go bad? Is there any way to test them?

I have an Auber temp probe and their braided RTD cable.

 

[dyqik]

Yes, braided cables can go bad (break in a cable), the connector on your control box can go bad, the cable to PID inside your control box can disconnect or the terminal to board contact inside the PID controller can break.

You need to measure various bits of the circuit with a multimeter to find the flawed component. First measure the resistance across the sensor at the cable connector. It should measure as somewhere close to the resistance given in the chart here at whatever temperature it's at between one terminal and either of the others (e.g. 108 Ohms at 21C/70F, 100 Ohms at 0C/32F). Between the other two terminals should measure much lower.

Then move back through the circuit towards the PID checking the resistance still reads correctly (you'll need to disconnect the terminals at the PID controller itself).

If the sensor reads correctly all the way back to the PID, the PID controller itself has gone bad. It may be fixable, or it may not. My JLD-612 PID controller went bad and was giving readings that fluctuated significantly. Nothing obviously wrong inside the controller (dry solder joints etc.) so I just replaced it with a MyPin controller.

 

[PLC-Guy]

UUUU Displayed TA4 PID Cntrl
The input signal exceeded the measured HI range, or TC break. (User Manual)
Built 1 For Friend, No Longer Here, Will Take a Shot @ This For Ya.

; No RTD Connected Showing Same Thing:
Use Multimeter/Ohms, Measure RTD Ohms, 1 White Wire(s), 1 Red Wire(s)
ie; Room Temp 70 Deg= Aprox 110 Ohms, Ice Cube Chill, Ohms Drops/Lighter Increases
If You Have a Resistor 97-145 Ohms [2-Wire Pt100 RTD] Install It, Pins 7&8
Remember Your RTD Is a Resistor

If You Are Using a 3-Wire RTD & Only Have Ohm Readings With White Wire & Only 1 Red Wire, Then Its Now a 2-Wire RTD & You Have
To Remove The External Jumper Between Pins 8&9 On The TA4
No Ohms Reading w/White & Any Red(s)= Failed RTD

http://drzeke.com/s_PT100+RTD+Table+Fahrenheit/

Check Wiring/Loose Wire(s) For RTD [Pins7-10]
If Using 2 Wire RTD, No External Jumper Installed Pins 7&8
3-Wire RTD, External Jumper Installed Pins 7&8
4-Wire RTD, No External Jumper Installed Pins 7&8

Still Nothing, Verify TA4 Settings; LSP-Low Temp Setting USP-High Temp Setting Range
Vefify (InP) Input Selection Setting TC: K,J,T,E,S, Pt100, Cu50
Factory Default is K
Verify MAX Input Limit & MIN Input Limit

Ref: TA4-PC5-2012-latest-manual.pdf
TA4 Wiring https://www.homebrewtalk.com/showthread.php?t=570172
Hope This Helps

View attachment TA4_PC5-2012-latest-manual.pdf

 

[R2Brew2]

Wow, thanks for the information. Now maybe you can explain this to me before I lose my mind...

I must admit I'm pretty much a novice when it comes to using the multimeter for anything other than volts, but I thought I'd try to follow your instructions. No luck, I wasn't getting any readings that made sense based on the information above (user error, no doubt). To add to my confusion, I have a 3-wire RTD (2 reds and 1 white), but did not have the jumper between 8&9 like PLC-Guy said was needed. Out of sheer curiosity - remember, this has worked for me for months, I promise - I tried making that jumper connection. Suddenly, it worked! And it was accurate! But...what?! How was it working previously? I don't remember making the jumper connection before; I don't think anything fell out randomly (it certainly wasn't in the control box); and the connections on 8 and 9 were still very tight. Was the magical beer fairy helping me out before? Or have I simply lost it...

 

[PLC-Guy]

It's Also Getting Late for Me Here, But Food For Though.
Maybe During Initial Setup, 3-Wire RTD Had a Loose Connection, Red Wire,
Pin-9, Maybe Intermediate Loose Connection Inside Crimp Connector,
TA4 Sensed a 2-Wire RTD Setup, Playing Around w/RTD Wiring Created
3rd (Red)Wire Connection, Now It's Really a 3-Wire Requiring Jumper.
Your Problem Might Happen Again, Possibly Due To The Crimp Connections,
Crimps Are Large Compared To RTD Thin/Small Gauge Wire Used.
If So, Solder Connections Up If Not Done, Watch Your Heat During Soldering.
Could Be Bad Connection Inside Cable On Sensor Side As Well.
Hopefully Not The TA4 Was a Intermediate Root Cause.
As Far As Meter Goes Set To OHMS, Meter Leads, 1 to White, Other to 1 Red
Should See a Ohm Value (2-Wire RTD) Leave Meter Lead Connected To White,
Connect To 2nd Red, Not Using 1st Red with It, Should See Ohm Reading,
Very Close, If Not Identical To 1st Reading (3-Wire RTD=Like 2 RTD's In 1)
So If It Happens Again, Your In a Bind, Revert Back To a 2-Wire RTD, &
Remove Jumper, 1 of The 2 Red Wires Hopefully Will Provide OHMs
Feedback To Your TA4.
That's My Story & Iam Stickin Too It
Glad Your Up & Running

Wow, thanks for the information. Now maybe you can explain this to me before I lose my mind...

I must admit I'm pretty much a novice when it comes to using the multimeter for anything other than volts, but I thought I'd try to follow your instructions. No luck, I wasn't getting any readings that made sense based on the information above (user error, no doubt). To add to my confusion, I have a 3-wire RTD (2 reds and 1 white), but did not have the jumper between 8&9 like PLC-Guy said was needed. Out of sheer curiosity - remember, this has worked for me for months, I promise - I tried making that jumper connection. Suddenly, it worked! And it was accurate! But...what?! How was it working previously? I don't remember making the jumper connection before; I don't think anything fell out randomly (it certainly wasn't in the control box); and the connections on 8 and 9 were still very tight. Was the magical beer fairy helping me out before? Or have I simply lost it...

 

[augiedoggy]

I do not have the jumper wires on my td4 with pt100 sensors.
Also I second the comment above the stainless shielded cables are very cheaply made and use very thin wire . They kink and short easily, and catch on everything. I have discontinued using them for this reason and went to these with teflon shielded cables which are better and stronger. I have had your issue multiple times prior to that.

http://www.ebay.com/itm/RTD-PT100-T...959914?hash=item3ab3ff5b6a:g:kbUAAOSwAYtWINyv