How accurate is the Apex temp probe out of the box?

Maximus

Maximus

Active member
I just hooked up the temp probe on the Apex and was wondering how accurate it is out of the box? Is there a way to calibrate it based on a known temp? I wish I had some sort of lab grade thermometer but I don't. I tried the ice water trick and the temp got as low as 43.7 and it didn't seem like it would go lower after 15 min. I could have swore the temp should be in the low to mid 30's. Any ideas? Btw, I don't have my tank yet as it is on order. Thanks.
 
The temp probe is calibrated at the factory to each base unit using a NIST standard and should be VERY accurate.

You cannot calibrate (nor really test) using ice water since the temperature of ice is WAY out of the way of the expected range and the temp probe may be less accurate that far away from the normal tank temp. If you want to test it then you would need a NIST calibrated thermometer (you might be able to locate one for $50 or so (that is what I spent on mine).
 
Thank you Ken. I sorta figured that the probe wouldn't be as accurate at those lower temps. Can the entire probe be submerged? I've had an AC3 in the past but feel like this is totally different. I tried to hook it up to my dsl router but I am computer illiterate and had no idea what to do. I have a mac btw. Sorry Ken:)
 
One more thing. After I disconnected the ethernet cable from my router, my dsl just froze up. I had to wait 20 min and had to reset the router and the dsl modem. Any idea why it would do that?
 
Yes, the temp probe is submersible.

The Apex connects to the router the same but it might make your life easier if you turn off DHCP and use a static IP address for the Apex (DHCP is on by default). If you leave DHCP on then you will need to setup a DHCP reserve for the Apex so that the address doesn't change and cause the Internet connection to fail.
 
I just compared the apex probe to a glass thermometer and it looks like it is about 1-1.5 degrees off. Apex read 72.5, glass thermometer read 71. I suppose that's not bad. I have to find another thermometer now to see which one I go with.

Creetin, did your Apex read 3 degrees high or low?
 
Creetin said:
My probe was 3 degrees off. I calibrated it to a good mercury thermometer.
Click to expand...

A NIST calibrated thermometer? Stock thermometers can be off by 3-5% over their range which can be many degrees.
 
Just to compare; using a NIST thermometer I checked my new Apex units (yes > 1) and both where spot on. If you do an "Init All" then the calibration will be wiped out but even in that case I have found that the calibration offset tends to be quite small (1-2 degrees F).
 
No, it was not a NIST thermometer. I need to track one of those down! However, if I measure the temp with 2-3 other thermometers, I think I will be satisfied. After all, 1-2 degrees shouldn't hurt anything as long as the controller maintains the same level of error over its lifetime.
 
Agree, tank temp is more about stability though sometimes folks get too caught-up in accuracy.
 
Ken, if something goes wrong with the Apex unit, I hear that you can set the heater to normally off. How can I do this? If I set it to normally off, then will the Apex turn off the power to the heater outlet in case of emergency?
 
Maximus said:
Ken, if something goes wrong with the Apex unit, I hear that you can set the heater to normally off. How can I do this? If I set it to normally off, then will the Apex turn off the power to the heater outlet in case of emergency?
Click to expand...

You might be referring to the "Fallback" statement which can be added to each EB8 outlet program and tells the EB8 what to do in case communications is lost with the Apex for more than 1 minute.

With regards to heaters directly; you should always have the heater set to a few degrees greater than the highest temperature you would have the controller use so that 'if' something went really bad then the heater would override itself. It is also good (for heat and cool) programs to add program statements that handle the rare cases of temperature probe fails. When a temp probe fails 99% it goes either high (to near 120) or very low (to near 20) so it is very easy to program a condition in the program so that you don't over cool or over heat your tank.
 
Thanks again. I don't have another controller for the heater yet. The Finnex will plug into the Apex directly. I may buy a Ranco for backup duties.
 
kenargo said:
... If you do an "Init All" then the calibration will be wiped out ...
Click to expand...
Crap, I think I had to do an init-all back when I was struggling with dupluicate EB8 entries and there was no way to remove modules.

Oh well, what can you do. I'll check if anyone in my local reef club has a NIST thermometer.
 
HeneryH said:
Crap, I think I had to do an init-all back when I was struggling with dupluicate EB8 entries and there was no way to remove modules.

Oh well, what can you do. I'll check if anyone in my local reef club has a NIST thermometer.
Click to expand...

It most you might be off by .5-1.5 degrees; it wouldn't be so much as to cause problems.
 
You must log in or register to reply here.

Similar threads

R
How is my chemistry looking?
Replies
1
Views
194
Uncle99
Uncle99
C
Can’t keep overflow box balanced
Replies
2
Views
132
Cruzersmith
C
T
Tank Crashing
Replies
19
Views
605
brandon429
brandon429
E
What's Old is New Again
Replies
2
Views
481
Uncle99
Uncle99
Brian60077
Today is the 1 year anniversary of my journey back into saltwater
Replies
3
Views
305
Brian60077
Brian60077
Back
Top