ECC Forum

I use the BCS 460 with probes designed with the controller.
All three used to work perfectly and always matched the gauges in my kettles. Recently my RIMS tube temperature probe is reporting around 10 degrees hotter than the liquid in my mash tun. I have ran over 25 batches through the system and only the last three have had this problem. The last batch I had to go in to the process editor and adjust the temperature of my mash to 165 to achieve 152 degrees in the mash tun.
Do the probes fail? Can they lose the calibration?

Hard to say what's going on. You'll need to pull the probes out of the RIMS and MLT to check their corresponding temperatures in some water.

I would fully expect the temp coming out of the RIMS to be higher than the actual MLT temp. How much different though is dependent on too many variables, so you need to pull the probes out to determine if one is actually off from the other.

I have tried a second temperature gauge in the MLT and it read the same as the first temperature gauge.
Yes there generally is a temperature lag, between the rims and mash tun. The rims stops heating when it thinks it is holding the temperature at 152 when it is actually holding the temperature at 142.
Very strange that it is happening after 20+ perfect batches and now it is consistently off by 10+ degrees.
I will try dropping the RIMS probe in the boil kettle and measure the differences between it, the boil probe and boil temperature gauge.

Best to do a Ice Bath Test. Thermoworks has how to make a proper one.

I had one probe read crazy for about a week and figured it was the Patch cable. Order a new one and guess what? The old one decides to fix itself!

I just thought of a reason that it fixed itself. I did a restore from a backup. If for some reason any of the Coefficients had been changed accidently, then this would have restored them. I would almost bet that was what happened. I can promise you that after years of doing some corporate in house computer support, you can change things accidently without ever knowing about it. Novel had a log that kept who deleted files or modified them, I restored deleted files that were "never" deleted by the person that deleted them. Have you ever been typing a document only to have it start somewhere other than the end of the line? You moved the cursor by an accidental set of keystrokes that you were not aware that you did. Since the "Save" is implicit on field exit in 4.0, you might have entered a Coefficient field by accident and changed something.

All that being said, it could also be a physical problem.

When trouble shooting probes:
1. Observe the Physical wiring.
2. Check the Coefficients
3. Switch Probes
a. If you can switch between two Probes (M12 or Short leads), do so.
b. Switch the Probe Wires on the BCS to a different Temp Probe #
4. Does the issue follow the Probe or the different probe, Temp Probe # or Wiring?

Every Solder Connection, M12, and Wire End Connection is a source for an issue. Try to keep connections to a minimum. In general, solder connections should be avoided if possible in data wiring. On my system I run shielded 18 awg twisted pair to a metal box where I have Panel Mount M12 Disconnects. The 18 awg does have a solder joint to the M12 Disconnect. I then use a 3 meter patch cable with M12 Disconnects to the Probes which also have the M12 disconnects. I know that 18 awg is way overkill, but I had that wire available. In reading some Robotic blogs, they suggested 18 awg for data wiring. Before I rewired, I had been using Cat 5 24 awg cable for the Probe Wiring without any issues until i got some EMF. I re routed the wiring and also enclosed in metal conduit. I could have re used Cat 5 cable, but decided to use the 18 awg instead. I did run a single pair for each probe and the only shared ground was a ground bar next to the BCS itself. Previously I have used one of the wires in the Cat 5 as a shared ground in the M12 Disconnect Metal Enclosure.

I do not have patch cables. That is how I wanted to order them, but all I could find in stock were 1/2" MPT probes with 8' leads. They are hardwired at the BCS 460 controller.
It looks like probes are still on back order since August of last year.
I have never restored a back up file.

Thank You for the suggestions. The tests are exactly what I am going to try. Need to find out if it is the temperature sensor, cabling, or the controller input.

Thank You again

Take a look at the Coefficents. They Should all be the same. You can also "restore" the defaults with the Calibration Utility. I suggest that if the Coefficents are good, make a backup, I make backups all the time. You will not be sorry that you did.

I have three probes:
(2) 1/2" MPT 2" long (TPBCSTF1202) BCS Temp Sensor with 8' lead
(1) 1/2" MPT 4" long (TPBCSTF1204) BCS Temp Sensor with 8' lead

The probe that I am having issue with is the 4" TPBCSTF1204. Should it have the same coefficienty?
I have tested all three probes at several temperatures and the 4" always registers 7 degrees warmer. I also switched the inputs and the problem follows the probe.

I emailed Electric Brewing Supply, who I purchased them from, but they have never replied.

All three inputs are set at the same coefficienty. One of them still reads 7-8 degrees higher than the other two, even after I move it to another input.
Kind of crappy since replacement probes seem to be impossible to get and Electric Brewing Supply does not respond to emails.

UPDATE
I did call and talk with Ryan at Electric Brewing Supply. He is very nice and has been extremely shorthanded lately and that is the only reason he did not get back to me. He is going to call Curtis at Brewers Hardware to see about sending out a replacement probe.

I have brewed a few batches with the faulty probe, but it kind of sucks to set the temperature 7-8 degrees higher to achieve the temperature I want.

Have you calibrated the probe? The standard coefficients work for most new probes, but there can be variations and you may need to use a custom derived set of coefficients for that probe. Thermistor based temperature probes work on a circuit resistance. Cable lengths, connectors, assembly, etc. can all affect the readings. If you run through the calibration procedure, you'll come up with a set of coefficients specific to that probe. This is a pretty standard way to get your readings corrected. The fact that you say it consistently runs 7-8 degrees off sounds like the probe is stable and just needs to be corrected by calibration.