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Intelligent Power switch for the Taranis

When Gordon asked me if I had a power kill switch for one of my models, it was with some embarrassment that I had to say no! However, I've just spent some considerable time creating one which I'm reasonably happy with. I looked on the internet and there were some suggestions as to how to do it, but either they didn't work because they were created for a different version of the firmware or they allowed the motor to be switched on even if the throttle was high.

This version works for the current firmware (2.2.4 in my case!) and won't arm the motor until the throttle stick is moved to zero. This means that you can't enable the power if the stick is above zero. The power will only be enabled after the stick has been moved to zero. It'll make sense when you use it!

It's based on two lines in the 'Logical Switches' section on the Taranis and one line in the 'Special Functions' section. They are shown in the pictures below.

The Logical Switches can be on any line as long as 'V1' in the 'Sticky'  line refers to the other line correctly.

The Special Function can also be on any line in the Special Function list as long as it refers to the correct Logical Switch. Also notice the '!' before the Logical Switch number.

I've used the 'SD' switch on the Taranis to operate the kill switch. It could be changed to any switch on the Taranis, but take care to make the correct changes in the Logical Switches section.

When the SD switch is up, the motor is killed. In either of its other positions (SD is a three position switch) the motor is enabled, but it will only be enabled after the stick has been moved to the zero position. Turning the motor on while the stick is in any position other than zero will have no effect until the stick is moved down to zero after which the motor will work normally. It makes much more sense  when you see it working!

The Special Function also assumes that the throttle is set to channel 3. If yours isn't you need to change the Special Functions line to whatever channel you use for power.

I'll leave the reader to work out the logic of how it works!

If you want a further description, ask me up the field sometime, but if you leave it too long I will probably have forgotten how it works!

Have fun!

Uploaded files:
  • Thrtl_logical.jpg
  • Thrtl_SF.jpg

How do you get those screen shots?, I have a similar tip and would like to show how I programmed it.

Get to the appropriate place in Open Tx Companion and press 'PrtSc' on the keyboard, then run the Paint program (or something similar) and use the  'Paste' option. You will get the full screen so use the 'Crop' function to select the bit you want to save. Then save it as a JPEG which you can then upload on to the forum.