Power Jazz vs Jazz 55

[Flybar-less]

Do the regular Jazz controllers work better then the PJ crap?

[Voodoo]

Hey John,

Y crap?

[Flybar-less]

It gives a different headspeed at each startup. Gov works well, but inconsistant flight to flight. Kontronik says that it reads startup voltage rather then RPM. I can fly several flights same headspeed, or or several flights with different headspeed. I have gone through the battery charging ritual some have suggested without any improvement. Time to move to some thing else.

[Eyon]

my standard Jazz's are spot on, perfect head speed every time. Not sure about the PJ but ive heard nothing but perfection about them

[TomC]

It gives a different headspeed at each startup. Gov works well, but inconsistant flight to flight. Kontronik says that it reads startup voltage rather then RPM. I can fly several flights same headspeed, or or several flights with different headspeed. I have gone through the battery charging ritual some have suggested without any improvement. Time to move to some thing else.


John,

You're right, all Kontronik Jazz escs, incl the PJ, use voltage to set the headspeed. Depending of the quality and age of your flight packs this can give a diff hs at your idle-up throttle setting. This seems to get worse as your # of cells in series increases. For example, on my 15s Ion-x, the diff can be as high as 250 rpm. On 10s this diff is a lot lower, but it is still there. On 5s the diff is not significant.

I've found 2 work-around solutions. One is to have a diff Idle-up throttle setting for each kind of pack. The other way is to use the prog card and go to auto-throttle mode (APM). Then startup in Idle-up2 at 100% gov setting, let it stablize, and then flick it into Idle-up at a lower hs and go fly. For some reason, this gives a lot less diff hs between packs (+/-50 rpm).

Also, if you restart your heli with the same packs, even if you have only run it for 30 seconds, this will screw up your hs settings as well since the startup voltages will be a bit lower. Bit of a pain imop.

Good luck and cheers,

Tom C

[Flybar-less]

Tom,
Thanks for the info. My 4 packs are new and this occurs randomly with any pack. I may try the APM work around you suggest. I have been using a mix to move my gov setting up or down, but my ear is not good enough to set headspeed for a consistant tail setup.

[MrMel]

And to answer the question, No, all Jazz work the same way, they detect voltage and calculate the RPM range from that.

Knowing this, it actually very good for us.

Because a simple fact that probably no-one thought of, your "lower voltage pack" is less quality then your higher voltage pack, loweringt the RPM will also lower the overall Amp draw, preserving the pack making it last instead of puffing.

Think of that.

[TomC]

And to answer the question, No, all Jazz work the same way, they detect voltage and calculate the RPM range from that.

Knowing this, it actually very good for us.

Because a simple fact that probably no-one thought of, your "lower voltage pack" is less quality then your higher voltage pack, loweringt the RPM will also lower the overall Amp draw, preserving the pack making it last instead of puffing.

Think of that.

As usual, you make a very good point MrMEL!

I believe part of the problem is the way the Jazz esc's (esp the PJazz) calculates the initial startup voltage when you are in fixed throttle endpoint mode (via the prog card) and actually startup at say ~80% idle-up.
I rarely get a consistant hs an any of my packs on 10s or above and all my packs are good quality FP Evo's, just difff age/generations. Yet, when I use APM mode and startup in idle-up 2 at 100% and let the headspeed at ~zero pitch settle down and then flick it into idle-up 1 at 80% the hs's are very consistant (+/- 50 rpm).

In practise, I've found my Jazz 55-10-32 works much better and gives very consistant hs's on 10s in fixed throttle endpoint mode. It's the PJazz that I seem to need to do this APM work-around with.

Cheers,
Tom C

[MrMel]

Just a guess since I aint the developer of the Jazz governor,

When you use APM mode, you spool up the heli, a Lipo fully loaded has very little mah capacity in that top voltage.
So when you reach 100% RPM after about 20 seconds it has settled down probably around X.Xv per cell

That would probably be less variance there compared to a fresh unused pack unless the pack is really bad.

I suspect thats why you see more consistent RPM using the APM.
But like I said, its just a guess.

[TomC]

Just a guess since I aint the developer of the Jazz governor,

When you use APM mode, you spool up the heli, a Lipo fully loaded has very little mah capacity in that top voltage.
So when you reach 100% RPM after about 20 seconds it has settled down probably around X.Xv per cell

That would probably be less variance there compared to a fresh unused pack unless the pack is really bad.

I suspect thats why you see more consistent RPM using the APM.
But like I said, its just a guess.

MrMEL,

Good one Mate. I believe that explains it! Thanks.

Cheers,
Tom C

[Flybar-less]

What does your headspeed goto during 100% throttle?

[TomC]

What does your headspeed goto during 100% throttle?


John,

At 100% Jazz gov'd throttle, and ~0 deg pitch, I've found that most heli's wind up to about the same headspeed as a non-gov'd w/100% flatline throttle curve at zero pitch.

For example, my 10s Trex600 w/evo25 3700's and a 800 kv Tango 45-08 and 170t main 12t pinion (14.17 ratio) calcs a zero pitch hs ~ (10x3.7x800)/14.17 = 2089 rpm hs. I actually get a ~2200 hs which indicates my packs are putting out ~ 3.9 v/cell initially. I govern this back to ~2000 hs (78% throttle in my case).

The quality of the packs make a big diff as well imop.

Cheers,
Tom C

[Flybar-less]

I have another Power Jazz to try. Should I try APM mode. If understand you guys correctly, one "Idle-up" has a straight 0 to 100 curve and is used to stabilize RPM at 100% throttle 0 pitch, and is not use for flying.
My concern is overspeeding the head, especially for 10-20 seconds. The 1912H/1Y will turn 623 blades over 2,500 RPM. Just the governed RPM difference in the past has bent full shank bolts. I had a +- 15% correction mix setup previously to deal with this. Gov was set to 65-70%.

Any other tips?

As usual, you make a very good point MrMEL!

I believe part of the problem is the way the Jazz esc's (esp the PJazz) calculates the initial startup voltage when you are in fixed throttle endpoint mode (via the prog card) and actually startup at say ~80% idle-up.
I rarely get a consistant hs an any of my packs on 10s or above and all my packs are good quality FP Evo's, just difff age/generations. Yet, when I use APM mode and startup in idle-up 2 at 100% and let the headspeed at ~zero pitch settle down and then flick it into idle-up 1 at 80% the hs's are very consistant (+/- 50 rpm).

In practise, I've found my Jazz 55-10-32 works much better and gives very consistant hs's on 10s in fixed throttle endpoint mode. It's the PJazz that I seem to need to do this APM work-around with.

Cheers,
Tom C

[TomC]

John,

If you cannot re-gear so that your 100% gov'd hs is within reasonable limits then you should program your Power Jazz to fixed throttle points. Then you will use flatline idle-up throttle curves. Maybe start with 60% to be on the safe side, and increase this untill you get the hs you want. As long as your packs are similar, you should get pretty close results after this.

Cheers,
Tom C

[Flybar-less]

Tom,
I will go back to fixed end points and a 12 second spool up. From reading Kontroniks literature it appears the constant is not determined until some calculations are made + headspeed. So I will use the same start procedure as well. Stick to zero pitch, throttle hold, Ildle up, flick out of throttle hold. Take off once headspeed has settled.

Do you think lengthing spool up time will reduce error?

[TomC]

John,

Don't know about whether the longer spool-up time will ejfect this or not. I kind of doubt it, but who knows.

I personally like the 12 second Spool-up (default setting and the longest available) because is is nice and easy on gears. I've tried the 6 sec startup and as long as you pre-spin your blades, it's still pretty smooth.

A few of my flying mates like the 6 sec start since it allows them to abort auto's.

Cheers,
TomC

[fogger]

A friend of mine had similar issues on his 10s and 11s MA carbon99 E-conversions. He now uses the 100% throttle startup method, but understand that you don't need to let it see "true" 100% throttle for more than a few seconds. All this is doing is teaching the PJ what 100% throttle looks like on your TX. This only takes a few seconds. Then if you switch to your normal gov curve it should spool up to the correct hs.

I have read that sometimes it takes a couple tries to get the fixed throttle endpoint "teaching" with the prog card to "take" in the PJ, I do not know why this is. We have not tried this yet however.

The difference with the other Jazz series is that during the setup when you select governor mode (and lipo cutoff mode) with the stick programming method, that process teaches the jazz what low and high throttle look like, assuming you used a 0-100 throttle curve...

Here is a quote from Shawn's (OICU812) jazz setup thread:


Some guys are using 'fixed' instead of Auto(APM) but I have not found this to work very well for me. This requires you to plug the card battery plug to a lead (which you may need to make. since both ends need to be servo end-type plugs) that goes to your rx throttle channel and you need to fire up the rx from it's battery source and your tx need to be on in normal mode, low stick (using a 0-50-100 throttle curve). You then go throught the same select process but when you get to the stick position option and select 'fixed'. Then the light will flash over the low position. Make sure that your throttle stick is in low position (0%) and hold the select button. Then it flashes over the high throttle position. Move your throttle stick to high (100%) position and and then hold the select button until it goes solid. Unplug everything and you are done. If this works properly for you, you should be able to select say your 80% flatline curve right off the bat and it should spool up and stabilise at this lower hs all by itself. That is you will not need to start up at 100% each time. Works for some, so you might want to try it, I just did not find that the hs's were consistant (80% gov setting headspeed's could vary up to 150 rpm) but I think that this is because I'm using about 4 generations of FP evo cells that all have slightly different voltages. Funny, but when I use the APM method the 80% setting hardly vary's more than 20 rpm between different packs.

Anyway, hope this helps and good luck!

Cheers,
Tom C
__________________




Hope you don't mind me adding that info Tom :)

-Fog

[RockinRyan]

All this talk is a little troubling to me! I was considering the major purchase for a Power Jazz... I actually have only used a Jazz on my little TR450V2. I was just about to get a Jazz 55-10-32, then pondered the beast, now looking confused and a little saddened!

What would Brian Boitano do?
Ryan

[TomC]

Ryan,

I would not worry about all this too much. The Jazz escs work very well but like all escs, they have their quirks, which you can work around. Overall, I very happy with my PJazz. I also have a Jazz 55-10-32 and it works well. There seems to be less gov hs diff vs. batteries on the smaller Jazz 55.

If you need to pull big amps and high cell counts (15s) then the PJ is what you need.

Cheers,
Tom C

[cptsnoopy]

SAE is sending me several of their new 85amp 12s capable controllers very soon for testing. I will keep you guys updated on the results. I am currently using the older version in my Logo600 and I have another one in my brothers e620SE. Both have done very well. I have used them only in gov mode with great results until I tried it on the Logo600. I found out recently that the Hitec 6965 servo was a bad choice for the tail and it may be the reason I had some tail wag with the SAE controller. I have never had any of these SAE's fail like the CC controllers do. I have never had one thermal. I have burned one up that did not survive my putting double the rated amps through the motor and shorting the motor out. I am hoping that the new version is as good or better and that they are able to keep the price/performance ratio which was very good with the ones that I bought. ($139) for 12s-85amp with a good gov. These may be able to fill the gap between the Jazz and the PowerJazz at a much lower price.

Charlie
:)

[NTM]

SAE is sending me several of their new 85amp 12s capable controllers very soon for testing. I will keep you guys updated on the results. I am currently using the older version in my Logo600 and I have another one in my brothers e620SE. Both have done very well. I have used them only in gov mode with great results until I tried it on the Logo600. I found out recently that the Hitec 6965 servo was a bad choice for the tail and it may be the reason I had some tail wag with the SAE controller. I have never had any of these SAE's fail like the CC controllers do. I have never had one thermal. I have burned one up that did not survive my putting double the rated amps through the motor and shorting the motor out. I am hoping that the new version is as good or better and that they are able to keep the price/performance ratio which was very good with the ones that I bought. ($139) for 12s-85amp with a good gov. These may be able to fill the gap between the Jazz and the PowerJazz at a much lower price.

Charlie
:)

Send me one, I'll test it real good, lol !
No less than 6 cc85hv's have died in my heli, and the current jazz 55-10-32 that resides there needed some serious heat sink action to roll with the punches !
I'd be blown away if the sae could hang onto it's cookies and had a decent governor for twice that price.

The only esc I'm holding my breath for is the kontronic unit that'll go between the 55-10-32 and the powerjazz, it's supposed to have some nice features like anti spark,12s power handling, the traditionally polished jazz governor, and really high continous amp capability.
Due out for spring.

Regards,
Nathan

[cptsnoopy]

I mostly cooked the HV-45 controllers in my Logo10 setup on 12s. It spent many days on the shelf waiting for replacement controllers to arrive. After getting the SAE controllers the esc was no longer an issue. I sent you a PM with some info.

Charlie
:)

[OICU812]

SAE,, never heard of them..... Show us all a link please. :wink:

[cptsnoopy]

Ok, here are two pictures of the one I am running in my Logo600 right now. The extra lead is for the eagle tree motor rpm sensor. Here is the link to the SAE website on the page that shows the controller "coming soon". I have heard that the website will be updated very soon to have a whole new range of SAE controllers available.

http://www.sae-model.com/products_show.php?pro=58&class_no=4&language=en

Charlie
:)

[OICU812]

Reading the label this esc you are using is only good to 55amps? Does the governor work well or do you run fixed curves?