View Full Version : Castle Creations Thunderbird 54 and 4cell?

07-09-2009, 09:17 AM
Hi Guys A flying buddy was wondering if he could use his Thunderbird 54 Esc on 4cells if he added a seperate BEC, I've looked pretty much everywhere and came up empty handed... Has anyone try'ed this?


07-09-2009, 01:28 PM
Did you check the Castle website? Says right there that the Thunderbird line is only good to 3s.


07-09-2009, 01:56 PM

07-09-2009, 06:28 PM
Hi Guy's.... Yes I checked in the reg places like vendor specs... however there are a lot of esc's out on the market that say 3cell but will do 4cell if you add a seperate bec, I was just wondering if that was the case with these...

Has anyone tryd it?


07-10-2009, 08:34 AM
When Castle says the max voltage is 15 volts thats what they mean. Thats the point above which the smoke comes out.

4S lipos have a voltage of 16.8 volts fresh off the charger.

It will most likely be smokeville if you try it on 4S.

The Castle BEC's are only rated to 3S due to over heating of the BEC if you try to use it with 4S. That has nothing to do with the max voltage rating of the power fets.

07-10-2009, 03:26 PM
Has anyone tryd it?


Yes a number have tried it - and they report good initial results.

Not sure if they cook after a while, but I have not personally tried it.


07-10-2009, 03:51 PM
Exactly Mike, I made a big boo boo when I first set up my Shoestring conversion. I had a Phoenix 60 ESC and was initially going to run a 6s. Upon realizing I did not have enough power I went up to an 8s and got exactly what I was looking for, still using the Phoenix 60 which was only rated at 6s. It worked fine, no issues at all, counted all 8 cells and everything. A kind soul pointed out to me what I was doing and I immediately changed it out for a HV type ESC.

It may have only lasted one more flight, or may have never burned out, who knows, but why take the chance? Use the right ESC for the job at hand. Better safe than sorry.

Nothing worse than seeing a smoke trail from an electric plane while in flight!::o

07-10-2009, 04:17 PM
Most electronics can tolerate over amping, even to a large degree, for at least a while fairly well. You heat them up, they cool down and are fine.

Over voltage, more often than not kills them instantly. Even if it doesnt smoke instantly, it damages them over time.

Keep in mind too that if your pack is older or has low C rateing (hi Ir in other words) or if you have long leads or a poor connection between battery and esc, that you will be generating higher voltage spikes that can easily push an esc thats close to the edge into the smoke mode.

07-10-2009, 05:46 PM
thanks guy's I'll let him weight the consequeses... We we prob only going to run it at about 35amps max So I don't think Heat would be too much of an issue, but... as They say... those are the chances we take playing around...