Posts: 668
Joined: 1/22/2002 From: Omaha, NE, USA Status: offline
I am using a 14 MZ, and have to adjust the throttle trim before each flight to get the idle where I want it to be. IS there a better way to do this may'be put it on a switch?
Posts: 294
Joined: 6/10/2002 From: Placerville,
CA, USA Status: offline
quote:
ORIGINAL: rgreen24
I am using a 14 MZ, and have to adjust the throttle trim before each flight to get the idle where I want it to be. IS there a better way to do this may'be put it on a switch?
TIA
I use the throttle cut function on the 14MZ assigned to a switch . I set the throttle cut 'on' setting just low enough to arm the ESC and when I flip the throttle cut switch 'off', the motor goes to my selected idle speed without touching the trim at all. When I am ready to kill the motor, I just flip the throttle kill switch back 'on'.
Posts: 333
Joined: 2/27/2004 From: Benicia,
CA, USA Status: offline
I use something similar to Woodie except I use the slider on the left side (LST) to be my throttle trim. That way I can adjust it quickly and easily without having to use the digital trim.
Posts: 237
Joined: 11/29/2002 From: ohio,
OH, USA Status: offline
Another way is to copy your regular flying condition to a condition called startup, assign it to a switch, give it the highest priority. Set the startup condition throttle curve afr to 100%, make it seperate, set the normal condition throttle curve to 85% or whatever needed to get the idle you want, leave it grouped. Use the startup condition when arming the esc, switch to your regular flying condition when ready to go.
The Jeti Spin ESCs have the ability to set the actual pulsewidth as parameters both ways. Then you get all values fixed and don`t have to arm the ESC with full throttle each time. Combined with an "idle-up"-setting would give you both idle and cutoff as you prefer every time...
Posts: 276
Joined: 10/29/2002 From: Agawam,
MA, USA Status: online
Specific to the Jeti Spin 99…
At what point does the brake come on? Is it any time the motor RPM is exceeding requested RPM or does it only come on when the throttle stick is in the off position?
If the latter, then will not setting up an idle effectively disable the brake?
My last ten or so flights have been with the brake off and I don’t really see the need for an idle (or the brake!) RPM never drops below 1500 according to the data logger. …although I did flop a stall turn or two
Posts: 18
Joined: 10/14/2004 From: nsw, AUSTRALIA Status: offline
Scott
I have always been taught that the brake on an electric motor is only for gliders. For pattern and sports you want the brake off so that the prop idles when you cut the the throttle.
Posts: 237
Joined: 11/29/2002 From: ohio,
OH, USA Status: offline
Brake comes on at the off position so your right, you won't be able to use an idle. Some manuevers its nice to have, if you don't want it to activate just stay a click or two above the off position. I've got mine set pretty weak, just so the downlines are constant speed. 45 lines I don't let it activate.
Posts: 294
Joined: 6/10/2002 From: Placerville,
CA, USA Status: offline
quote:
ORIGINAL: rgreen24
Hey Woodie can you exapnd a little on how you set it up, what function you went into on the 14 to get it done?
TIA
OK, here's how I do it.....
But first, a little info on the Jeti 90 and Jeti 77 ESCs (non Spin version)
The default end points for the non- Spin Jetis are approx 1.1 ms for low and 1.8 ms for high throttle. I set up my radio so the default is not disturbed during a flight. When I say 'disturbed', the Jeti 77 and 90 will reset the high throttle ms setting to anything it sees over 1.8ms. So if your ATV on high throttle goes to 2.0ms then the Jeti will reset to 2.0ms at full throttle and expand the overall range of throttle throw. It does not increase the power to the motor, it just expands the range of throttle 'throw'.
Because of this, and I hate doing full throttle run ups or immediately after take off to set the high end ms setting, I limit my ATV on the throttle to never exceept 1.8ms. I have a Jeti programming box that reads the ms timing of a channel and that is how I determined where to set my ATV. This seems pretty consistant across 2 radios and 2 Jeti ESCs.
If you like to do full throttle runups (or you have Jeti Spins which are programmable for end points) then you can ignore my comments on high throttle ATV.
My throttle ATV settings in my 14MZ are shown in one of the attachments below. HIgh throttle ATV is at 73% and low is at 99%. The 99% setting is low enough for the Jeti to 'arm' (you have to be below 1.1 ms for it to arm). This is also with my throttle cut switch 'on'. The 73% high throttle setting is 1.8ms timing, equal to the default setting in the Jetis.
The second attachment is my throttle cut screen. I use the Throttle Cut (Linkage Menu) to set this up. I assign my throttle cut switch to SW-B but you can use any switch convenient to you and not currently used for something else. I have used SW-B for so long I don't want to 'switch' (pun intended). You can see the settings on the attachment below.
So I plug in the ESC with the throttle cut in the on (kill) position, the ESC beeps several times indicating the cookies are done ;-) and when I am ready to start I flip the throttle cut switch off and the motor starts at idle. You may need to play with your throttle trim a little to get the idle where you want it but after that, you don't have to touch the throttle trim. Same everytime.
Posts: 668
Joined: 1/22/2002 From: Omaha, NE, USA Status: offline
Thanks guys for all your help. I finally got it to idle without adjusting the trim everytime. Turn on 14MZ--- hit throtlle cut, trun on plane, take throttle cut off bump throttle up a tad and viola; motor runs on low rpm
Posts: 410
Joined: 10/23/2002 From: west hills,
CA, USA Status: offline
quote:
ORIGINAL: jooNorway
The Jeti Spin ESCs have the ability to set the actual pulsewidth as parameters both ways. Then you get all values fixed and don`t have to arm the ESC with full throttle each time. Combined with an "idle-up"-setting would give you both idle and cutoff as you prefer every time...
I recently tried to set fixed end points on my Jeti Spin and couldn't get it to arm in the airplane. I thought I had it figured out when using a pulse generator. If I turned the system on with a pulse width above the 1.0 msec I had set, and then dropped it to less than 1.0, it would arm. I couldn't do it in the plane. I gave up and went to auto low end and fixed 2.0 msec on the high. Seems to work. What is the trick to get the fixed low end to arm? You mentioned something about arming with full throttle?
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