Throttle Trim: all the way down?

[120ccpm]

I know it's not a Pro-specific question, but... do you guys keep the throttle trim all the way down? This is how I was told to do, so both my simulator controller and my coaxial radio are currently setup this way.
With the Pro and the Futaba 7C (first radio I have with digital trims) I totally forgot, but I don't seem to have any problems...
I never understood why throttle trim should be all the way down... could someone explain?

[airjawed]

I think only on Nitro helis do you have to keep the trim all the way down.

[kjdubuque]

I keep all trims on my radio at zero.

[120ccpm]

Good, thank you guys.

[Tucky]

All my trims are centered, except for the throttle one, if I connect my heli with the trim up, it won't bind. It get it as throttle up.

[120ccpm]

Originally Posted by Tucky

All my trims are centered, except for the throttle one, if I connect my heli with the trim up, it won't bind. It get it as throttle up.

Well... did you calibrate the ESC with the trim centered, or down? If you did the calibration with the trim down, of course you will have to keep it that way when you connect the battery, otherwise the ESC will think your throttle stick is not at zero...

[helidude71]

^^ exactly.
On my 7C all trims are centered.
Calibrated the ESC and done with it.

On the RTF kits with simple TX, the throttle trim is always down for the ESC to arm.
In other words the ESC needs to see an absolute zero to arm.

[Tucky]

I programmed the ESC with the trims downs. i'm not sure but I thought I read about it, or that the way I learned, I don't see ill behavior. now the interesting part would be if there's and advantage programming the ESC with trims down vs. centered.

[120ccpm]

It's interesting to see that people do things differently, although I really can't understand what's the advantage of keeping the throttle trim all the way down, particularly on an electric collective-pitch helicopter.
If someone knows, please explain it to the masses...

[airjawed]

If I had to generalize I'd say that if your ESC is programmable then your throttle trim should be centered. Most ESC's are and therefore you should center the trim. This is also important in order for TH and throttle cut to work correctly.

If you can not program the ESC then you may have to bring the trim down so that low throttle is recognized.

[Tucky]

Originally Posted by airjawed

If I had to generalize I'd say that if your ESC is programmable then your throttle trim should be centered. Most ESC's are and therefore you should center the trim. This is also important in order for TH and throttle cut to work correctly.

If you can not program the ESC then you may have to bring the trim down so that low throttle is recognized.

Both my ESC are programmable, and on both I did the programming with the trim down, I have no issues with throttle cut.

[airjawed]

Originally Posted by Tucky

Both my ESC are programmable, and on both I did the programming with the trim down, I have no issues with throttle cut.

On some ESC's it may be a problem though. The CC line uses a value lower than zero to throttle cut and a value near zero for throttle hold. If you trim down you may not get the results you are looking for which may be dangerous.

Read the instructions with your given ESC....that is what a person should do.

[Tucky]

I see your point, I'm still fairly new to Heli, only 10 months into the hobby, Have been thru 4 Heli, 2 E-sky and my first builds are my current T-rex 600 and 450Pro. So basically I'm still with the stock Align ESC's, I believe that the E-sky manual stated the trim down, don't have it anymore so can't check, I think that's where I got the idea of trim down. I'm thinking on getting a phoenix ice, so good to hear CC are different.

[mano]

I have an Castle creations ice 50 and I either have to put trim all the way down or use the throttle hold switch to get it to arm.

[airjawed]

Originally Posted by mano

I have an Castle creations ice 50 and I either have to put trim all the way down or use the throttle hold switch to get it to arm.

This is after you have done the throttle endpoints adjustment?

See bottom of page for adjustment instructions:

http://www.castlecreations.com/support/documents.html

[sarpilot]

Originally Posted by airjawed

This is after you have done the throttle endpoints adjustment?

See bottom of page for adjustment instructions:

http://www.castlecreations.com/support/documents.html

+1

It should see closed throttle based on endpoint on the low end. If you have to trim down something is wrong with the setup..... Make sure you have a linear throttle curve in normal mode when setting endpoints or it drives the CC software nuts. After setup you can return your normal curve to how you like to have it.....