Digital aquatics - Temp Probe Weirdness

[bryan3536]

I picked up a reefkeeper lite from a local guy who got an Apex month’s ago and had the RKL on a shelf. The temperature probe was beat up but seemed to work on day 1, but after I actually calibrated it, it started fluctuating by .1 degrees every second or so, with a variance of about .5 degrees. (It’ll go 78.3, .4, .5, .6, .4, .2 in the space of 5 seconds). It was enough to have the heater outlets clicking on and off constantly. Thought it was the probe so I bought a new one from BRS - installed it today, exact same issue.

Any ideas? I am calibrating by going to Modules, RKL, iTemp, calibrate. I let it sit for a good 20 minutes, but that number on the right fluctuates and never stabilizes. For what it’s worth, I put a new PH probe on the same unit and no issues.

 

[bryan3536]

I picked up a reefkeeper lite from a local guy who got an Apex month’s ago and had the RKL on a shelf. The temperature probe was beat up but seemed to work on day 1, but after I actually calibrated it, it started fluctuating by .1 degrees every second or so, with a variance of about .5 degrees. (It’ll go 78.3, .4, .5, .6, .4, .2 in the space of 5 seconds). It was enough to have the heater outlets clicking on and off constantly. Thought it was the probe so I bought a new one from BRS - installed it today, exact same issue.

Any ideas? I am calibrating by going to Modules, RKL, iTemp, calibrate. I let it sit for a good 20 minutes, but that number on the right fluctuates and never stabilizes. For what it’s worth, I put a new PH probe on the same unit and no issues.

Hey I just thought of something. I have three power strips and the salinity/ph module. Is it possible that’s too many with the RKL?

 

[n2585722]

You can only have 4 modules. That is 4. The iTemp plugs into the buss so every connector will add some resistance to the temp probe if you are using the iTemp. You can try the type that plugs into the temp port on the SL2 module. You can also try using the controller function and use a higher hysteresis value. That will reduce the cycling of your heaters. If your heaters or less that 300 watts you can use CH2 or CH3 to control the heaters. Those don't have relays so they won't click.

 

[bryan3536]

You can only have 4 modules. That is 4. The iTemp plugs into the buss so every connector will add some resistance to the temp probe if you are using the iTemp. You can try the type that plugs into the temp port on the SL2 module. You can also try using the controller function and use a higher hysteresis value. That will reduce the cycling of your heaters. If your heaters or less that 300 watts you can use CH2 or CH3 to control the heaters. Those don't have relays so they won't click.

Ok maybe a dumb question, but the iTemp probe itself counts as a module, and the SL2 (which I have) that has slots for ph/salinity counts as a single module? Or does each probe count as a separate module?

 

[n2585722]

Ok maybe a dumb question, but the iTemp probe itself counts as a module, and the SL2 (which I have) that has slots for ph/salinity counts as a single module? Or does each probe count as a separate module?

The iTemp probe does not count as a module. The RKL head unit has a temp port inside of it that is accessible via two of the six wires in the buss. Both temp probes are the same the only difference is the connector that is attached to the cable. The one used on the SL2 module will have a connector like the 2 switch input ports on the SL2 module. The iTemp probe has a RJ type connector that is also used on the buss cables. By the way your SL2 module has a temp port, pH port, salinity port and 2 switch input ports. You can use all 5 but the SL1 still only counts as one module.