PDA

View Full Version : Analog temperature probe and digital temperature probe in ExBox2, which one?



ss162400
11.11.2018, 09:09
I have a P3ex's own analog temperature probe. recently bought an ExBox2 and digital temperature probe. Now the problem has arisen. after I connect everything. I found that my digital probe and analog probe showed inconsistent readings. Then, I put them in the measuring cup of the same ice-water mixture. The result is 10.3 degrees Celsius for the analog probe and 6.3 degrees Celsius for the digital probe, which the gap is 4 degrees Celsius. However, in the sea at 27 degrees Celsius, the gap is almost 0.6 degrees Celsius. Since my conductivity probe relies on temperature compensation to be accurate, I have to choose an accurate temperature probe. So, which temperature probe should I trust? The analog probe or digital probe. By the way, according to 677/319, I calibrated the analog probe. I did not calibrated the digital probe since the lack of calibration data.

Please help guide. Thank you!

Please the below pictures for your reference:

11206

11207

11208

MatthiasF
13.11.2018, 13:20
Hello,

you cannot calibrate the digital temperature probe and can trust the measurement since it has only a tolerance of 0.5 deg. celsius.

faltaren
13.11.2018, 14:50
Not True. I have the p4 and ex2. They dont show the same. Even swapped probes. Same..

Skickat från min G8141 via Tapatalk

ss162400
13.11.2018, 15:23
Hello,

you cannot calibrate the digital temperature probe and can trust the measurement since it has only a tolerance of 0.5 deg. celsius.
But which I should trust?and it impact my conduct reading!
In fact, a tolerance of 0.5 deg. Celsius is a Cake, but I concern that the probe is faulty, so causes my conduct reading is wrong!
By the way, I just measured my conduct at 1.024 by GHL probe, but I measured it at 1.028 by Hanna HI96822.
I am confuse! and I just bought the conduct probe from Sewatec Web site.
The analog probe is old for 6 years and the digtal one is new and faulty, which is a disaster for me.
It is important that their readings is not 0, in the measuring cup of the same ice-water mixture.

Matthias
14.11.2018, 09:36
1. you can't calibrate the digital sensor - as the name says it is digital and already pre-calibrated from the chip-vendor
max. deviation is 0,5°C

2. you can calibrate the analog sensor - or better: you calibrate the analog input port of the ProfiLux input probe
BTW: 677/319 are the standard values - I doubt that this is the specific calibration of your ProfiLux
to recover your calibration values from factory perform a "calibration" on the device itself (see manual)

3. I would trust the dig. probe

4. "The result is 10.3 degrees Celsius for the analog probe and 6.3 degrees Celsius"
This is outside the allowed measurement range for aquariums and means nothing (range min. is about 15°)

5. you can always use the "adjust temp." feature if you don't agree to the readings

6 "The analog probe is old for 6 years and the digtal one is new and faulty, which is a disaster for me."
If you are convinced that the probe is faulty and it is a disaster for you I recommend to consider a new probe

ss162400
14.11.2018, 12:26
Thanks for your help! I need the manual for the calibration. Where I can get it? Other side, How much is the tolerance for the conduct probe

Vinny
14.11.2018, 23:31
Information on probe calibration and tolerance can be found in the P3 Programming Guide:
https://www.aquariumcomputer.com/downloads/profilux-3-3-1-programming-guide-v6-15/