Failsafe and setting testing on the TDR

[Puttputt maru]

It just occured to me that in Jan instruction for the TDR, he says never to run the motor on the bench at more than 30%, which I already did, for it will stress the power train.

Attention! Do not let the engine without blades run at a throttle specification of more than about 30%. If there is not any load due to the rotor the RPM values do not correspond with the values adjusted under load, i. e. the engine runs too high which may result in a damaged mechanics.

How do you test your failsafe and settings if you don't do it?

[Raptorapture]

I'd just lower your throttle curves to 35, 40 and 45 for normal, IU1, IU2. 30 is probably too low as it is close to a TH for bailout. Then reset levels and test rpms at the field with blades on. Truth be told be told I didn't spot that until I had already spun up on the bench.

[xioxia]

Attention! Do not let the engine without blades run at a throttle specification of more than about 30%. If there is not any load due to the rotor the RPM values do not correspond with the values adjusted under load, i. e. the engine runs too high which may result in a damaged mechanics.

Wrong, you have to check 0-100% throttle for vibration. After build/rebuild, crash and so on.

[mkovalcson]

Originally Posted by xioxia

Wrong, you have to check 0-100% throttle for vibration. After build/rebuild, crash and so on.

FWIW I've spun my TDR up on the bench many times with no ill effects that I can discern and I've used my SK-720 BE for vibration analysis on many occasions.

[Puttputt maru]

Originally Posted by mkovalcson

FWIW I've spun my TDR up on the bench many times with no ill effects that I can discern and I've used my SK-720 BE for vibration analysis on many occasions.

I figured as much but just wanted to make sure.

Of course if I'd do it for a full battery, it would be trouble but for fast check I do not think it is a problem.

[Groucho_]

Originally Posted by Puttputt maru

I figured as much but just wanted to make sure.

Of course if I'd do it for a full battery, it would be trouble but for fast check I do not think it is a problem.

I've used more than one full battery.

RPM readings under load or with no load, blades or no blades are identical.

That's what a governor is for.

[Raptorapture]

Originally Posted by Groucho_

I've used more than one full battery.

RPM readings under load or with no load, blades or no blades are identical.

That's what a governor is for.

It depends on the governor. You can hard set the rpm both from calculations or capture in use. However, the governor may also set the rpm as it goes without the absolute rpm being known. This is generally to support adapting to varying sized and tired lipo's. Using this feature is how I've oversped on the bench.

[Groucho_]

Originally Posted by Raptorapture

It depends on the governor. You can hard set the rpm both from calculations or capture in use. However, the governor may also set the rpm as it goes without the absolute rpm being known. This is generally to support adapting to varying sized and tired lipo's. Using this feature is how I've oversped on the bench.

I thought that part was a bit obvious, so I didn't mention it.

I've always set my governor to give me constant head speeds regardless of battery power or load.

[Raptorapture]

Originally Posted by Groucho_

I thought that part was a bit obvious, so I didn't mention it.

I've always set my governor to give me constant head speeds regardless of battery power or load.

The trouble is to set the governor without blades will by process most likely cause an overspeed or the condition mentioned in the TDR manual is what I was trying to point out. That's at least with the ESC's that I've been using.

[Groucho_]

Originally Posted by Raptorapture

The trouble is to set the governor without blades will by process most likely cause an overspeed or the condition mentioned in the TDR manual is what I was trying to point out. That's at least with the ESC's that I've been using.

Never had that problem using a kontronik helijive.

I've always set the speeds up without any blades.

I can't vouch for other brands of ESCs, though if you're setting up speeds correctly, using real-time RPM information via telemetry or some other means, it wouldn't be a problem with any brand.

[Raptorapture]

Originally Posted by Groucho_

Never had that problem using a kontronik helijive.

I've always set the speeds up without any blades.

I can't vouch for other brands of ESCs, though if you're setting up speeds correctly, using real-time RPM information via telemetry or some other means, it wouldn't be a problem with any brand.

Ah, therein lay my challenge, no telemetry.