Voltage drop issues

[wyx_]

Howdy howdy

Picked up a 22 5.0 for some stock/mod class racing and I've been having issues with my voltage readings on my DX5C. Turning right causes a bump of .1v and turning left causes anywhere between .2v drop to complete loss of power, even at full charge on the shorty pack. I'm completely stumped and unsure if it's because I need a BEC at 7.4v instead of 6v. Any knowledge would be appreciated!

 

[nino]

Inadequate battery or a very hungry steering servo? Maybe it's on the way out and pulling too much current? The bump when turning left is weird though...

 

[wyx_]

Inadequate battery or a very hungry steering servo? Maybe it's on the way out and pulling too much current? The bump when turning left is weird though...

Battery doesn't seem to make a difference. Using a GensA 60C shorty, tried it with a ProTek 120C LiHV and didn't see any change. The ProTek 160SS is a HV servo, but the pros use the Spektrum S6245 with no problems running 2S.

I really do think it's something to do with the built in BEC on a majority of the pro racer setups. HW XR10 Pro G2s, Trinity MX10 Pros, some stuff from Muchmore. All seem to have adjustable BECs up to 7.4v. My 10BL60 is limited to 6v/2A.

I'll pick up a HW G2 pro sometime in the near future and see if the BEC limit solves my issue.

 

[tntpoof]

the servo mixed with your esc is the issue as said above try a ubec but remove center wire from esc to rx or it will fry esc.

 

[wyx_]

the servo mixed with your esc is the issue as said above try a ubec but remove center wire from esc to rx or it will fry esc.

Definitely going to pick up a Pro G2 tomorrow. Needed the 10BL60 to replace my aging Tekin RS Gen1. Should be loads better.

 

[olds97_lss]

Yeah, it's likely your internal bec. 2amps isn't nearly enough really for a 1/10th vehicle. With the esc fan, motor fan chewing up 1/4 of an amp (or more, depending on the fan), that doesn't leave a lot left for the receiver and servo. If it's dieing completely on you in one direction but not the other, then you may be hitting a mechanical limit or something is binding causing the servo to work just hard enough to pull the amps beyond what the esc can supply.

Considering the speed/torque of this, I'd guess it would pull more than 2amps under load:
https://www.spektrumrc.com/Products/Default.aspx?ProdID=SPMSS6245

Why all company's don't list a stall current is beyond me... it should be listed on every servo on the planet. Basic necessary info...

I ran into a similar issue when I was using a castle mamba monster (the old one that came on the savage flux hp many years ago). I was fine until I installed a little stronger servo. You would hear the fans drop in pitch when I turned and occasionally, the receiver would brown out and the esc would "reboot". I threw a castle 10A bec on it to run everything and then it was fine.