6 Battery problems...

[revengeturbo]

I`ve recently tried to install an extra 2 batteries into my xmod.
The model has had 4 4562 fets stacked on the original fets and works with no problems on the standard 4 batteries with a 32t double wound motor.
However, when I try to run it with 5 or 6 batteries installed it staggers until it has some motion, like it`s being turned on and off really quickly, then gets what seems to be full (7.2v) power.
I`ve explored all obvious avenues and all is well with connections, etc.
What is going wrong? Has anyone successfully installed this mod. without trouble?
I`ve read that the board will max out at 8.4v, but that 7.2(6bats.) isn`t a problem.
Thanks for your time...

[jamiekulhanek]

I dont think that has anything to do with voltage. Check your Tx battery, that can cause problems.

[RacinSkillZ101]

your problem aint that bad, obviously try what jamiekulhanek said, but if that dosent work then you have to change the capacitor on your motor, the capacitor is the little black thing soldered to your motor case, all you have to do is go to rs and pick up a 470uf to 1000uf capacitor, their somewhat big so you'll have to make it fit. the purpose of a capacitor is to store energy somewhat like a temporary battery, so that when you hit the throtle their is a small amout of energy to feed your motor as the electricity flows from your batterys to your motor, since you added more batts, you increased the distance the electricty must travel before reaching your motor, so by installing a bigger capacitor their will be enough energy to get your motor started as the electricty from your batts travel to the motor, hope this helped if you got any questions just ask

[aperson]

actually there are 2 caps but ok. the disk type stops "noise" from interfering with the reciever board. back on topic, the way RS has the cylidrical cap wired is so that you wont get reverse voltage to the ESC and fry it. by putting a bigger one on you are just "buying more insurance" it might work though. but replace both caps. the semi proportional effect is messed up by the motors noise. try replaceing the disk type first. since you are putting almost a full 7.2v in the motor the brushes are arcing more than with 4.8v or 6v. try putting a real noise cancelling capacitor on. go to your local hobby shop and ask what kind of capacitors they use on electric cars. if you put one of those on it should solve the problem.

[revengeturbo]

Thanks for the help fellas. TX batt. is a brand new energizer alkaline, no worries there! I did try some capacitors from one of my mate`s mini-z motors, never checked the rating though(dumb...) I`ll get a couple of the high power blue capacitors off of an old 540 modified(1/10th scale) motor. See if that shuts the bastard up!

[jamiekulhanek]

Originally posted by revengeturbo
I`ll get a couple of the high power blue capacitors off of an old 540 modified(1/10th scale) motor. See if that shuts the bastard up!

Uh, high powered??? No such thing matey, just go to an electronics store and get 3 "103" ceramic cpacitors and put them on.

DO NOT WIRE AN ELECTROLYTIC CAPACITOR ACROSS THE MOTOR TERMINALS....MAKE SURE ITS A BIPOLAR IF YOU MUST DO IT.

[revengeturbo]

Yeah, high power = 50volt max current, as opposed to any number of capacitors rated at 1 to 5 volts that will max out under 7.2v... Using capacitors from a mosfet system designed to take 7.2 to 8.4v (473, 50v) and 40a max drain seems the foolproof approach, right? Even if it`s not, it`s stopped the interference, so I`m not messing with it.

[jamiekulhanek]

Originally posted by revengeturbo
Yeah, high power = 50volt max current, as opposed to any number of capacitors rated at 1 to 5 volts that will max out under 7.2v... Using capacitors from a mosfet system designed to take 7.2 to 8.4v (473, 50v) and 40a max drain seems the foolproof approach, right? Even if it`s not, it`s stopped the interference, so I`m not messing with it.

A). 50v does not mean high powered, it means high voltage. High voltage doesnt mean high power, power is the multiplication of volts x Amps, i,e. 7.2V x 3A = 21.6 WATTS of power.

B). If you understood the basics of electronics, you would realise that you need a 10v or so cap. Any higher and it is wasting space.

C) are you talking about a booster cap or ceramic suppressor caps??

D) 50v max current....WTF that is a crock of **** and makes no sense.

If it is a "booster cap" don't wire it onto the motor, you can seriously damage or blow the FETs.

[revengeturbo]

Thanks for your help, mate, you must be really smart... However, as I stated in my last post, the SUPPRESSOR caps from the 7.2v setup have solved the problem, so you can stop posting on this thread, it`s done.