Coolant Temperature

[Bo_Hannington]

Hi, I seemed to start this coolant temp thing off, and have been patiently waiting for the next update to get this sorted. Excitedly went and installed V3 today. Sorry to say that, although I can now select type 4, it reads the same as type 3. The sensor is, as I originally mentioned, one of the CHT sensors that came with the Rotax 912ULS, and there is a 1K pull up res and it is connected to GP1. Today, with an ambient temp of 18degC (and this is approx what is measured by the other temp sensors (oil, CHT(Jtypes)), the coolant is reading 78degC.
Looks like everyones got a similar problem.
Bo Hannington

 

[josok]

Ok, first flight done, regretfully without proper operating or reliable coolant temperature indication.
Remember, this was a bug in the previous firmware version, and should be ironed out in this actual version.
Selecting sensor type 4 brings the display to -99. Selecting 3 back once more brings the display to some, maybe sensible level.
I don't really care where the mistake is, it's not my wiring or pull-up, its a bug in the system and i want it solved.
This is not up to your reputation.

Regards,

Jos Okhuijsen

 

[dynonsupport]

Okay, we found the problem.

Coolant temp 4 will read correctly near 160 degrees F (72-ish degC). When we tested with a 120 ohm resistor we didn't find this, since we happened to choose the exact resistance that is dead on.

Below 157 degrees F, it's all messed up and can read high, -99 or +999.

Above 170 degF, it's kind of right, but it's always low and maxes out at 237 deg F.

We'll look in to what we can do. Sorry for all the trouble and thanks for the data everyone provided.

 

[josok]

Great, thanks for the reply, a lot more at ease now

Regards,

Jos Okhuijsen

 

[alan_milner]

Great news !
I'm in a similar situation to Jos with the flight testing on a Rotax and coolant temp would be a good thing to have at the moment.

 

[alan_milner]

Hi Dynon

Do you have an estimate for this fix yet?  

My aircraft is about to fly again soon and I need to somehow make provision for coollant temp monitoring.

I don't think I posted the info from my tests, I think it's redundant now, but here goes anyway...  It was about 24 C ambient.

	Type 1	Type 2	Type 3	Type 4
VDO Sensor	21 C	52 C	22 C	999 C
120 ohm	74C	115C	79C	80C
1Kohm	18C	49C	20C	999

 

[dynonsupport]

It will be in our next update for sure. We're already in beta for the next firmware release, so we hope it won't be too long, but we don't have a specific date yet.

 

[josok]

Hi Dynonsupport,

Somewhere else in this forum you promise that the next software update will be BIG and that it will take at least six months.
Please don't disappoint those who are patiently waiting till this bug gets wired out please?

Regards,
Jos Okhuijsen

 

[dynonsupport]

I'm not sure where you found the info about it being 6 months, but the next release is already in beta. If you're really anxious to try it out, I suggest you join our beta test group.

 

[alan_milner]

Just for the record I uploaded the v4.0 EMS software and the coolant temperature is now working perfectly with the Rotax sender.

Thanks. Alan

 

[dynonsupport]

Great to hear!