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Powering up a servo centering tool

mayan

Well-known member
#1
Hey everyone,

A few days ago I burned the balance connector on my 2S battery which I used for flying but mainly for checking things were working fine before hitting the field. Any how I used it also to power the servo balancer tool that I have because I knew how to use only one cell so not to over power the tool as it needs only one cell of power. Can I do the same with a 3S battery? If so how?

Pictures would help :).
 

CarolineTyler

Well-known member
#2
You could, just need to connect it across only the ground (black) and the second along.
rcheli-diagram-balance_jst-xh.png
what I use is a cheap USB charging lead, hacked off the micro USB connector and spliced on defunct servo lead powering just the ground and positive. That way I can power my servo checker from any USB socket (computer, powerbank, wall plug etc.)
 

Gazoo

Active member
#9
Yes, in-fact that is what I use, 4 AA batteries. Similar to what @Gazoo uses.
True. The only difference, I guess, is that the phone charger that I use is a regulated 5VDC supply. Four AA batteries would start at 6VDC and then drop until unusable. Either way, they both work great.

@CarolineTyler also has a nice method by using the powered USB port on a computer but it would not exactly be portable though.
EDIT: I see that Caroline also uses the wall wart and power pack as well.

I have also tried to use those cheaper USB rechargeable power banks/sticks but they cannot provide enough amperage and tend to brown out under a load. I do use them for a small 25mW FPV camera though.
 
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#10
Oh, related public service announcement.

If you are testing an ESC that has a BEC in it, you don't need to plug in separate power since that's what the BEC is for.

If you are going to test an ESC that doesn't have a BEC, do NOT plug a servo tester into the balance port of the same lipo. You'll short one or more of the battery cells through your ESC's ground wire. Use a second battery, or other external, 5v power supply. Ask me how I know this...
 

mayan

Well-known member
#12
Oh, related public service announcement.

If you are testing an ESC that has a BEC in it, you don't need to plug in separate power since that's what the BEC is for.

If you are going to test an ESC that doesn't have a BEC, do NOT plug a servo tester into the balance port of the same lipo. You'll short one or more of the battery cells through your ESC's ground wire. Use a second battery, or other external, 5v power supply. Ask me how I know this...
Generally I don't recommend test ESCs with a sero centering tool burned one that way, might be just bad luck though.
 

mayan

Well-known member
#13
Thank you all for the advice. Now I'll be able to connect the electronics for the Tedge tonight :). I like the idea of using a usb cable, seems like an option worth having around even if I have a battery laying around.
 

FDS

Well-known member
#16
You can move the pins to match the +/- if it’s a balance connector type JST. Or put a servo plug on, just use the right pins to match the polarity, you don’t need signal.
 

Bricks

Well-known member
#17
I am lucky enough I fly Nitro so have a bunch of NIMH 4 cell packs laying around and LIFE batteries only problem using LIFE is the starting voltage is 7.5 and some servos do not care for this much, smoke baby smoke.