Temp probes go Haywire!!

Get help and insight.
Post Reply
dtfeld
Posts: 61
Joined: Thu Oct 27, 2011 7:02 pm
Bot?: No

Temp probes go Haywire!!

Post by dtfeld »

I have multiple ECC tempo probes installed. They are calibrated and work most of the time, but every so often, the temp reading go haywire. I usually push gently on the probe where the wire exits the SS probe and they settle down again nicely. It looks like EMI to me but have not been able to link it to anything in the system (pumps, elements ect.) as this happens in a steady state condition (heaters on, pumps on) after 20-30 minutes and erratically at that. This happens in both a SS HLT and my rubbermaid plastic cooler, so I'm thinking its not a grounding issue

Any ideas?
Attachments
haywire2.PNG
haywire2.PNG (88.96 KiB) Viewed 8012 times
haywire.PNG
haywire.PNG (47.91 KiB) Viewed 8012 times
JonW
Site Admin
Posts: 1726
Joined: Sun Jul 18, 2010 7:51 am
Bot?: No
Location: Huntington Beach, CA
Contact:

Re: Temp probes go Haywire!!

Post by JonW »

Do you have a jumper going from earth ground to the BCS 5V ground? Several of us have had sporadic temp fluctuation issues that were solved by placing a jumper between the AC and DC grounds.
dtfeld
Posts: 61
Joined: Thu Oct 27, 2011 7:02 pm
Bot?: No

Re: Temp probes go Haywire!!

Post by dtfeld »

I have a BCS-462...there are 3 separate GND pins, I have only the 2 of the three grounded. Do I need to ground all three as I'm not using all the Temp inputs and didn't ground the ones associated with the unused temp inputs.
Attachments
BCS-462 Pin out
BCS-462 Pin out
BCS-462 PIN Out.PNG (27.65 KiB) Viewed 8005 times
Last edited by dtfeld on Wed Jul 04, 2012 11:57 am, edited 1 time in total.
JonW
Site Admin
Posts: 1726
Joined: Sun Jul 18, 2010 7:51 am
Bot?: No
Location: Huntington Beach, CA
Contact:

Re: Temp probes go Haywire!!

Post by JonW »

They're all common ground. Are you saying you have a jumper wire going from two of them already to an earth ground?
dtfeld
Posts: 61
Joined: Thu Oct 27, 2011 7:02 pm
Bot?: No

Re: Temp probes go Haywire!!

Post by dtfeld »

Yes, I had only two connected. I just reran a ground from the AC ground bus to all three GND pins, running a test now...seems to have addressed it.

I'll have to do a brew session to confirm, I've thought I've solved this before... :D
dtfeld
Posts: 61
Joined: Thu Oct 27, 2011 7:02 pm
Bot?: No

Re: Temp probes go Haywire!!

Post by dtfeld »

Currious...maybe ECC can answer...

Why 3 separate GND pins? Are they connected (common ground) or are they separate and if so why?
JonW
Site Admin
Posts: 1726
Joined: Sun Jul 18, 2010 7:51 am
Bot?: No
Location: Huntington Beach, CA
Contact:

Re: Temp probes go Haywire!!

Post by JonW »

They are common, that's why I was asking if you had already done two of them. Seems only one should be fine.

Pretty sure the multiple ones are just so you have multiple connection points without having to cram wires in or use a junction block.
dtfeld
Posts: 61
Joined: Thu Oct 27, 2011 7:02 pm
Bot?: No

Re: Temp probes go Haywire!!

Post by dtfeld »

I jumpered all 3 to the AC ground and the problem has stopped...who knew? Is it possible that having two grounded as opposed to one or all three created a ground loop?
User avatar
ECC
Posts: 676
Joined: Fri Sep 12, 2008 12:29 pm
Bot?: No
Contact:

Re: Temp probes go Haywire!!

Post by ECC »

The are all common (you can verify with a continuity test), we just provide multiple pins for convenience.
dtfeld
Posts: 61
Joined: Thu Oct 27, 2011 7:02 pm
Bot?: No

Re: Temp probes go Haywire!!

Post by dtfeld »

Thanks for the clarification...
Post Reply