MGM problem, need help on 8S

[Over_revO]

Hi guys,

Im new to the forum and a member of this forum i know suggested me to login and talk about my problem....


My friend bought an MGM Car/boat TMM 12545-3 45v

The controller work well on a single 4S , it give the right voltage to the motor,
but when we connect 2X 4S in serie (8S) the controller hit the LVC.

I tried to run the race mod 1 and race mod 2 , but it still hit the power cut-off...
or the power reducer fonction....

the wiring is okay, the plug are MP jet 6.0mm
Wires lenght from the batteries to esc is 18 cm long.

Anyone have a clue of what is happening?

Thx for any idea


Mike :)

[jantagg]

It worked on 4S because, that is the controller default setup . You have to program the controller to recognize the 8S setup.

[Over_revO]

I tried in automatic, and on 8 cell already , it did nothing different. :(

Heres the programming option i have,
http://i193.photobucket.com/albums/z75/mike_peperni/PIC_2481-1.jpg

i tested the following

A: bidirectionnal
B1: 8 cell
B2: 0
C: Li-xxx (3.20v) also tested automatic
D: skipped
E: Limits according to transmitter
F: Brake soft 3
G: 0.13sec
H: NO
I: YES
J: 6% neutral zone
K: No
L: we run a 4aa to power the receiver
M: Power reduction or Cut-off
N: 20 degree, tried also automatic
O: NO
P: 8khz
R: Se version
S: Se version

Any suggestion for the programming will be welcomed! :)

Thx !

[Fluid]

...when we connect 2X 4S in serie (8S) the controller hit the LVC.
This of course makes no sense as the voltage is doubled so no LVC is likely. I suspect that the settings may not be what you think they are if you programmed by the transmitter. I program mine with my PC so there is no question, but missing a beep can put you off with the transmitter method.

If that is not the case, set the timing on 5 degrees, set G to 0.65, J to 15%, S to zero. See if these changes help. Does Se refer to sensored motor? What motor are you running?



.

[Over_revO]

The Se version is a different esc? it say if i dont have the SE version it make no difference what ever setting i use for the 2 last.

I use an unsensored motor. Mamba 2650kv, yes i know, its not build to handle 8S, my friend dont care if it explode.... :)

But even without the motor plugged, the voltage drop.

It will kick at 27-28 volt sometimes but will drop very fast almost instantly on what look like a lvc, cut-off , power reduction, depending on what it is setup....


thx for the help!

[Fluid]

I use an unsensored motor. Mamba 2650kv, yes i know, its not build to handle 8S, my friend dont care if it explode....
Your 'friend' may not care, but the ESC may. It may not support a motor speed in excess of 80,000 rpm.


But even without the motor plugged, the voltage drop.
You can't measure the true voltage drop without the motor connected. This could mean nothing, or it could mean an ESC problem. You never want to run an ESC without it being connected to a motor. This could now be your problem.....

Send MGM an e-mail explaining the problem. They have been very good at answering and trying to help. Their English isn't perfect but it isn't bad. Give them a try.



.

[Over_revO]

I sent 2 email already, he have that provblem since day one, we used the multimeter just 2 days ago, before this , the motor was always connected to the esc.

And we can still make it run like it was the first day..


I will tell him to test with his NEU 1515 2.5d , 1650kv, to see if its alright.


thx for the info.

And my english is probably not better than MGM staff lol my first language is french...


anyway thx! :)