[deanc]

Does anyone have the same fault as my loop temperature code does?

Quite often, actually more often than not, the loop temperature reads 213.1 degrees, rather hot I think. Now I'm pretty sure the scrubber doesn't quite generate that amount of heat, so I have ruled that out.

So continuing to cycle through the menu numerous times and the error either :-
1. Repeats itself with a fixed series of numbers, some minor variations.
2. Sometimes new random numbers come up in the sequence.
3. Sometimes the error isn't there and the temperature reads fine.

Heres a typical sequence * is probably OK:-
213.1
129.0
196.1
26.5 *
213.1
26.5 *
213.1
129.0
196.1
26.5 *
213.1
129.0
26.6 *
91.1
32.8
0.4
198.6
193.0
26.5 *

It seems to depend on how slowly I scroll the menus as waiting a few seconds sometimes gets the actual temperature, there must be a timer in the code somewhere -- like resetting back to the root display.

Bringing back some ancient yet fond systems programming memories in a previous life, I would guess that some code is written into the memory where the sensor value would be stored? Hence the repeatable results.

Although I doubt whether its even worth repairing or feasible, I am a little concerned from the pov of verifaction/validation of the code that this sort of thing could be occuring in some other parts of the software.
The water temperature reads fine. 2.01 k and it happens above/below water and any time I can reproduce this.

I would post a photo, but the manage attach button doesn't work.

[denismc66]

I have noticed something similar on my unit once or twice, i have the temperature set to metric and when i enter this menu the loop temperature can appear as high as 200 degrees. I am only new to the unit so i will watch this in the future. I have apecs 2.5

[Muzz]

Quote: (Originally Posted by denismc66)

I have noticed something similar on my unit once or twice, i have the temperature set to metric and when i enter this menu the loop temperature can appear as high as 200 degrees. I am only new to the unit so i will watch this in the future. I have apecs 2.5

You really need to slow your breathing rate down a bit.

[Gadget]

the reason you see the fault is because of the cable length between the hanset and the head. the sensors are annologue and occasionally they read a bit of spurious data. scroll around to the screen again and it will be fine.

[deanc]

Quote: (Originally Posted by denismc66)

I have noticed something similar on my unit once or twice, i have the temperature set to metric and when i enter this menu the loop temperature can appear as high as 200 degrees. I am only new to the unit so i will watch this in the future. I have apecs 2.5

Thats interesting in version 2.5, a common bug to 2.01 may exist. I wonder if ISC could ever reprogram the computer, say it was more serious, like a fault in random PO2 readings, Steve?

Quote: (Originally Posted by Gadget)

the reason you see the fault is because of the cable length between the hanset and the head. the sensors are annologue and occasionally they read a bit of spurious data. scroll around to the screen again and it will be fine.

Dont agree on the cable length having anything to do with it. I do scroll around 16 times and that hardly affects the cable length, can it. Its a software issue, like you said sporadic *data*.

You may be right on a faulty thermocouple/resistor, but this sequence seems too repeatable for the wiring to be faulty.

Of course its analogue, there would be an analogue-to-digital converter ADC to convert the resistance/voltage/current to binary coded decimal BCD or alike for the display, with signal conditioning or a lookup table or math function to condition the signal into an integer celcius/farhenheit number, and add a false decimal place. This is the likely bug, in the conversion math routine.

I wouldn't know the circuit diagram but guessing its a 2-wire RTD then the cable resistance is negligible compared to say a platinum PT-100 ohm resistance at 0 degrees, and 0.385 ohm/degree. Open circuit goes 0 ohms. 3-4-wire RTDs can go kilometres.

If it was a thermocouple then its a junction which only forms at two dissimilar metals, type K Cr-Al. The cable (twin-core) can be hundreds of metres long, i.e. like in process control industry with no real effect. Open circuit goes 0 uV

Really the cable is just so negligible, unless the insulation has worn through or the junction is loose (i.e. a broken weld/resistor). They work or they dont.

The analogue-to-digital may even occur in the head/computer, not the handset, maybe there's serial communication between the handset and computer?