some excavator questions... esc,bec, radio and battery

[schmoking]

soo... i blew up 3 esc`s for my escavator (4200xl v1),
also think i may have damaged 2 more, but they work... for now.
i had a light swich short out, that burned 3 of them to death... then during some testing i accidently hooked up a shorted out servo,
heard some sounds i didnt like and there was an electrical smell,
but the pump motor esc and my last turn motor esc are working now after i hooked up a bec for power supply and pulled the red wires from the esc`s.


1. i want to get the sabertooth esc, and im planning on some other upgrades,
but for now i gotta make some other priorities... so i was looking for a cheaper alternative, just to get the tracks running.
im clueless when it comes to electro motors and esc`s, so i have been looking around and found a few that i thought might work...

https://hobbyking.com/en_us/quicrun-...5-brushed.html
http://www.rcmart.com/1040-brushed-c...?cPath=1560_51
https://hobbyking.com/en_us/hobbywin...-for-1-10.html
http://www.rcmart.com/tritronic-wate...?cPath=1560_51

they range from 25a to 60a... the rc4wd replacement is 40a(i think), but no way these motors draw 40a?
my pump motor a robbe 5055-45 has a 50a esc... but from reading the manual a 30a esc is recomended.
the sabertooths i think are 25a. so the motor are drawing these amps? not the esc feeding them? right?
anyways... does any of these esc look usable for trackmotors? or does anyone have a suggestion for a cheap alternative?


2. after some searching i figured out that when having 4 esc`s hooked up to the receiver its not good to have them all power it...
and after me hooking up the shorted out servo, the pump and turn motor esc`s wouldnt work right until i hooked up the bec.
this is the rc4wd yellow bec that came with the 4 valve upgrade kit.
i hooked red and black to the battery, and got 5 volts for the receiver... works fine, but it also has a white wire, what is this for?
did i hook this up right? after searching i couldnt find any other bec`s with 3 wires...?


3. the transmitter i have is the fly sky th9x... that came with the excavator
in aux channels i have
channel 5 as pit trim(the pot on the front) i use this to control pump motor.
channel 6 as hov pit (left lever) for track 1
channel 7 as hov throttle (right lever) for track 2

i used to have the pump motor revving up sometimes when i used the tracks, i finally figured out why...
if i take the left lever down then release it, then take the right lever up then release it channel 5 will changer rpm on motor...???
this is also visible in the display menu,
when i only have the radio powered that channel 5 will change when i do this... (but only if i have it set to pit trim)
to set it back to normal i can repeat the same movements or pull the left lever down twice.
this seems oddly specific to be some interference causing it,
but i been through the settings on the radio and i cant figure out if this is a setting,
even in a fresh profile it will do this, but only with these channels and selections.
anyone else have this happen? is it supposed to do this?


4. this is probably a stupid question... but im tired of burning my electronics.
i bought some lipo batteries i planned on using for my transmitters, but they are 25c and have really thick wires...
the old one i used have thin wires and is just 1c... could the 25c ones burn my transmitter?

sorry about the long post, but this stuff is confusing me...

[Wombii]

4: As long as the number of cells / voltage is correct, you're safe. 25c vs 1c together with the thicker wires means it can safely handle a higher current load.

[schmoking]

thanks for clearing that up...

[frizzen]

I don't have any hydro excavator, so i'm answering in general.

Don't feel bad, I think everybody here has let the smoke out of some parts at least once...

0
Pull red wire at rx plug from *ALL* the esc, test again with the bec powering the rx. Some might come back to life.

1
There are some chinese Sabertooth style dual channel mixing escs, but the reviews seem to be typical for Chineseium. Some are flawless, some go poof. How many amp do your motors need?

The motors can't use more amps than they're rated for at stall, if you go with a much bigger esc it can reduce the low speed control some.

2
The white wire would be for signal, bec doesn't care about signal. Keep or delete it as you feel like

3
Uh. I hope someone has done a walkthrough on that radio already, plane to surface setups are confusing.

4
Doesn't matter. The lipo 25c means it can charge/discharge at up to 25 times the capacity. So a 1Ah 25c pack could do 25Ah if it had to. A 1Ah 1c can only do 1Ah state of change.

[schmoking]

thank you for the reply!

i pulled the red wire and retested the other esc`s, thanks for the tip.
but unfortunately i could not resurrect them, they had already passed on..

as for the motor amps...
i did some searching, i could not find the exact same motor, but a similar motor of the same brand said 1.2 amps at stall and the upgrade kit im planning on getting said their motors draw between 0.5 and 3 amps...
so i guess all the esc`s i linked to should work fine.

i will be getting a sabertooth after the summer... so il probly just try a normal brushed one, then i got some in reserve for the turn motor
ill search some more to try and find some that have 100% power on reverse and can turn off the brake function.