Ashnook

I am looking at a 2 fuse twin with a battery in each (2200ma 4s) and linking them as parallel. Should be ok ?

Good points! Need to do more thinking. Model has yet to be started building so plenty of time to get my mind round things - one motor is SO much easier??? Brian

Many thanks for your inputs, the 4-Max sheets look interesting. I think I will go for a separate battery for the receiver/servo's rather than tie off the LiPo's. Interesting throttle connections Chris, I assume your transmitter can configure this arrangement!. Thanks for the help, Brian

Is there an article or discussion somewhere that goes into detail about how to connect up a twin brushless system? I am well used to single electric and want to build a twin. Thanks.

Thanks Andy.

I am looking for the Lyra Bi-Plane article from the November 1993 RCM&E as I have the plans and want to build one. Can anyone help please? Thanks, Brian

Yes, my Ballerina is electric too, again, battery through a removable top hatch. The PS-2 will also be electric. Not got round to studying the plan yet. Would be interesting to see someone who has done an electric conversion. Currently building another Lyra, 1990's bi-plane plan. Had one for years and really liked it, cannot remember what hapend to it! Brian

Just got the Mag, lovely looking plane, thanks. Will definitely go on my build list!

Is there anyone making a cut wood pack for PS-2? I have built and flying the Balerina from a wood kit - nice plane, always attracts comments!.

Count me in too!

Sounds like a vote for 4s over 3s

Posted by Dave Hopkin on 31/12/2014 12:11:51: Ashnook, I agree you will lower the current on a higher voltage by adjusting the prop load to get the wattage you want, but dont assume that increasing voltage will reduce current (if nothing else changes) it wont, on the same prop current will increase Its a triangular balance, voltage/current./prop load - where we can influence only two factors, voltage and load Increase either of them and current and wattage will increase... Be wary of going too low on your ESC I think its better to have plenty of current headroom on an ESC rather than take it closer to its limits - I think they will probably last longer that way All points well taken Dave. In most cases (except the experiment with a friend on Monday I am designing the setup from scratch using the desired power as the starting point. I have read where one should allow an excess of 15-20% on the esc.

Yes Dave I agree with all you are saying. As well as taking the KV into account (I work on 800-1000kv for my type of aircraft) I use the watt-meter as my bible in terms of atcheiving the desired power-to-weight balance for my setup. I haven't just swapped a 3s for a 4s but rather decided I want, say, 500W for this model and used the watt-meter to get that with the right prop, the only thing I don't check, and perhaps I should, is the RPM of my setup. I do know that for my 500W the current flowing through the setup is lower than for the similar 3s setup and that makes me feel better and posibly be able to use a smaller ESC. All this discussion is useful to me as I still am learning about Electric power as I am like many 40 year IC guys trying to get to grips with this new capability.

Hi Dave, according to the power calculation, watts = current times volts for the SAME power (that's the key) the current will reduce as the voltage increases - got to! Brian

Hi Frank, I built and OLD wot-4 kit and converted it to electric using a 5055 1KW motor! I use 2 4s-2200ma batteries in parallel to give me 4s-4400ma. I did not need to add any weight to the tail and it flies like a rocket (if you want) for 8-10 minutes. Brian