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T'REX Controller on Wild thumper 6WD

Hi, I just put the new T'rex controller on my Wild thumper 6wd, and i put the bluetooth module to controlled by my smart phone, but the problem is , it's running very slow, and lack of power.......

VID-20140718-WA0004.mp42.05 MB
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i am working on wild thumpher 6wd with the same components you have used but i am very new to this. Can you please guide me with the electrical schematics or perhaps pictures of the connection to and from the trex motor controller . 



Start by reading the manual and making sure you understand it.

For example, if you have the board in low voltage mode and put a high voltage battery (more than 8.4V) then you will probably damage the board.

Ok, if RC control has the same problem then it is unlikely to be electrical noise. The RC transmitter works on a different frequency and is much more powerful. Please note: Do not run control wires (such as the 4 core extension cable) parallel to hig power wiring. The strong magnetic field of the high current wiring will induce current into the control wiring (See short story below).

First thing to do is to get rid of the ridiculously long wires between the controller and batteries. The added resistance is only small but in a high current system it will severly limit the maximum current.

At the same time long wires generate many times the electrical noise of short wires. This is because  the electromagnetic field generated by the wire depends on length as well as current. In this case you have high current and huge lengths. A total receipe for disaster.

If you still have the same problem when your wires are a "Sane" length (as short as possible) then we can rule out high resistance and electrical noise.

That will leave us with either a bad battery pack, jammed motor (or in one case, a motor with a different gearbox ratio) or faulty controller.

For now I consider faulty controller unlikely since the problem seems to affect both left and right outputs equally.


Story Time!

When I was an apprentice working in Hazelwood power station (Victoria, Australia), the electrician teaching me was assigned a job to repair some low voltage signal wiring that allowed the control room to monitor the speed of a rising conveyor.

The circuit was only low voltage (50V or less) so minimal safety measures were taken (fuse removed). Unknown to us, the signal wires had been run parallel with the main power cable for the rising conveyor. This cable carries 3 phase power at 6600V, 400A per phase. The reason for such high power is the conveyor lifts 100's of tonnes of coal about 20 storeys up into a storage facility.

The electrician teaching me was working on the isolated, low voltage signal wires when the conveyor started up. Motors always draw a lot of current on startup, esspecially when they are trying to lift tonnes of coal.

The result was that the electrician received a shock that threw him backwards through the air several meters. The shock was later measured (they re-enacted the event) at about 20,000V! As a result of this accident, safety proceedures and wiring practices were changed.

The moral of this story: Never run control / signal wires parallel with high current cables such as battery and motor cables.




Christ, did the guy recover?


Oh, that radio system is at 2.4ghz. It likely won't be in the exact same spot in the 2.4ghz band as Bluetooth and is of course a far far more powerful transmitter but it is still a similar frequency to Bluetooth. With the transmit power of an rc transmitter though, I can only come to the same conclusion as you on it not being a problem with interference on the receiver.

When I used the RC, it totally cannot move, no action at all 

now i use the 4 core cable to mount the receiver away from the controller, the situation got better, at least it can move a bit faster

Please suggest what controller can i use for my wild thumper ? I tried wild thumper controller and t'rex

thank you!!!

You are not listening to what I say. There is nothing wrong with the T'rex controller. It is specifically designed for the Wild Thumper. Check out the video here: https://www.sparkfun.com/videos#all/_a6E0E_-XaE/185

Start by shortening the power wires and sheilding the receiver. Then try another battery.

try to use RC, but it cannot move either

, but it cannot move

I think the problem is electrical noise interfering with the bluetooth signal. Mount the receiver away from the controller and it should be ok.

Hi, I try to use the male-female cable to mount the receiver away from the controller, but the problem still the same


I already shorten the wires, but the result still no improved