I just pulled this out and posted it in a separate post.  Just how important is data logging?  And does the Eagle Tree eLogger really work?   

I just read up on the Eagle Tree eLogger.  Looks like a really good tool to have if you are using the JR timer with a cheep speed controller that does not have data logging built in.  Looks like the advantage of this system is that you can own one and move it from airplane to airplane.  Perhaps once you get a system dialed in you can unplug the system to save weight.  Once an aircraft is setup and working do pilots look at the data from every flight?  Not ever having data logging capability I don't know how often you look at the data.  I can see using it for prop testing etc but do you need to look at every flight? 

This logger works with any timer. For me it would be a great tool to have in order to fine tune a system. I currently use a Jeti ESC that has no logging capability. Things I would love to know and have no idea what is actually happening are the throttle signal that is output by the active accelerator and what Amps am I actually drawing during the flight. You can fly 100 years with a system and if the system is drawing a max of 20A, for example, and if you run a 70A ESC then you have 100 years with 2-3 extra ounces of weight that you where moving around for no reason. I would love to use a 30A ESC if I can but I don't know that at this time. Another place for this is to different motors prop combinations. I think it is worth the investment. Once you have a good idea what works best in your model you remove the logger and fly normally, without it. Another use for it is if you suspect fowl play and you are not sure, you can reconnect the logger and compare notes. 

Currently on my model only god knows what is happening in my system. I have no clue what throttle output commands are coming from the timer, also I have no clue what are the actual power requirements for this system, I would like to try a 5S a 4S with motors with various Kv values but have no idea how to find out if I am withing the system limits or where are those limits. For sure what i have now is way overkill, and heavy.

You can not optimize/tune your power train without data. You can not see or hear electricity you must measure it. The Eagle tree is a good product. I used one extensively. Yes you will take it out of the circuit once you have the setup dialled in. There is a lot to consider when trying to set up an electric power train. More than than an IC engine.

Kim

Hi John, it all depends on how technically involved you want to get. I've had my Eagle Tree data logger since 2009 and find it invaluable, especially when I was developing my timer system. Since then I still use it a lot, but then I am the curious type of person that enjoys knowing what makes things tick. I was so impressed by the Eagle Tree system that I asked them for the agency for South Africa. I ordered a small amount of various bits and pieces to get going but I only sold about 2 or three systems, and they were to R/C folks. I soon discovered that the vast majority of pilots are not really bothered by the finer technical details.

So if you are trying to optimize/tune an electric setup, then what Kim says is 100% true. The products are really good and the back-up service from Eagle Tree is just as good.

Keith R

I am a retired electrical engineer.  So inquiring minds want to know.  LOL   I may well invest in one.     If it works half as good as your KR timers it's got to be OK.

Hello,
I attempted to use the Eagle Tree eLogger during ground tests with Spin66 ESC and Igor's active timer.
When I powered the system, the motor started but run only for about 2 seconds and stopped.

I suspected some form of conflict between eLogger, Spin66 and/or active timer and never repeated the test.

ELogger works in the system containing KR Governor and Cobra 40+ and 60 Amps ESC.

Comment: Spin66 has the ability to log certain flight parameters (ESC temperature, max. and min. current, time of flight etc.) but some of these numbers are wrong. For example, the max. and min. in-flight currents are wrong. I have contacted Jeti but never received convincing explanation regarding the root cause of these errors. The ESC attempts to log something though and this may conflict with the eLogger actions.

I would love to measure the current v/s time during the pattern flights but of course until I know the root cause of problems I will not install eLogger in my models.

Regards,
M

Hi Keith,
I will talk to Loren and will repeat the ground tests.
Regards,
M