TOT light B206 question

[two0six]

Hello,

Wondering if you guys have any answers, I have had the TOT light come on whilst connecting the ground power to the helicopter. This has happened 3 times in the past 2 weeks!

As I plug in the ground power the light comes and on. On one occasion the TOT read 460 degrees before a start?

Very weird, it only does it when connecting the G.P. any wise words would be most helpful!

Thanks

[JTobias]

Hi,

I've heard of this happening before. Someone with far more mechanical/electrical understanding of the aircraft systems will probably explain it better to you, but I don't think its anything to worry about.

I presume that you have a TOT reset key ?

Joel

[Geoff Williams]

Applying the ground power is the cause

The NATO connector that is on the 206 is specially designed with the control pin being shorter than the 2 high current pins. This is to ensure that the power is there before any control circuits are activated.

If you plug the connector into the aircraft THEN apply power from the battery cart/APU, you defeat this protection in so far as everything becomes active in the aircraft at the same time. This scrambles the logic of the TOT light circuit.

So, only connect the APU/cart lead to the aircraft when it is live and you won't have a problem.

Geoff

[longbox]

I have had this before, quite normal sadly, don't get in the habit if you have a key of just re setting, another odd ball of the TOT gauges with lights is to show 3 to 4 hundred degrees when the batt is selected on even though you know it's cold, the only fix fire her up and it will re set and catch up. Always observe the numbers regardless

[two0six]

Thanks a lot for the help..... The nato plug is always wired up to 2 x 12v batteries in series before plugging her into the nose of the a/c. Its weird cos it only happens about every 10th start. I am bush based so I have the key sent in every few days. The 2 x 12v batteries are getting tired, I only get 2-3 starts before needing a charge. The a/c battery is fine I just like to keep it good and assist with externals whenever I am at the bush base with the thought being that 2 x car batteries are cheaper to replace than a concord Jetranger battery.
Starts are perfect with a peak of of 720 and the start only taking 28 seconds....

[two0six]

TOT light Happened again!

Yesterday I was back at base, used the key to switch off the light in front of the engineer he turned the battery on and the light came on without any externals even connected.

Engineer frowned and then in a grumpy voice said he will need the machine for 2 full days of trouble shooting

Sounds like a small problem being made into a big problem.....

Any thoughts would be much appreciated!

[Gomer Pylot]

Let him have it. Something isn't right, and you don't want to be flying it when things aren't right. Get it fixed.