Programmable probe option not working???

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sparxfly
Posts: 71
Joined: Mon Aug 31, 2020 5:57 pm
Location: Waikato, NZ
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Programmable probe option not working???

Post by sparxfly »

Hi Rainier-

I think there is a problem using the programmable probe option- in the SIM at least (not tested yet in actual hardware)
  • iEFIS G3 SIM V 1121 (fresh download)
  • COOLANT channel set to programmable probe
  • programmable probe set up in equal ascending steps 20C..160C between 1000..4000 ADC
  • using a simple text special item picking up RDAC1 coolant temperature
  • ramping the simulator RDAC coolant slider up/down, the display behaves as if an NTC sensor down in the lower 25% input range, not a linear progressive 0-5V sensor
  • I have cycled through the coolant probe options in case there was a 1-off issue, but no joy
Stuart
NZ MGL dealer
rainier
Site Admin
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Joined: Fri Aug 28, 2020 7:03 pm

Re: Programmable probe option not working???

Post by rainier »

Remember it assumes a NTC probe of unknown characteristic - it wants to see the resistance (and thus voltage across the probe) decreasing with temperature.
sparxfly
Posts: 71
Joined: Mon Aug 31, 2020 5:57 pm
Location: Waikato, NZ
Contact:

Re: Programmable probe option not working???

Post by sparxfly »

That stuffs up my plans!
I had asumed it could also be configured as a general purpose 0-5V analog input using the programmable probe option to calibrate it.
Would be a nice option (hint!)
Stuart
NZ MGL dealer
sparxfly
Posts: 71
Joined: Mon Aug 31, 2020 5:57 pm
Location: Waikato, NZ
Contact:

Re: Programmable probe option not working???

Post by sparxfly »

I found another way to skin the cat....
The current input was not being used, so I configured it to behave as a GP 0-5V input.
Zeroing current at sensor minimum and tweaking the current gain to give the desired full scale value at sensor maximum, you can use it as a GP analog input and link a display item to it.
The upper and low level warning and alarm thresholds also work fine- even with the low level values greater than zero.
Bingo!
Stuart
NZ MGL dealer
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