Electric problem

joksu

Member
Messages
8
Location
JKL
Hi,

Just made the first run with my new FG Moster Truck. The car was working fine for the first ca. 30 minutes, but suddenly lost the control of throttle/brake servo .

After checking more carefully, throttle/brake servo doesn't react to the trigger at all and steering servo also turns only slightly even if the trim is at top position. At the same time when I turn the wheel, there is a very small movement in the throttle/brake servo. The whole issue 'resets' after I unplug the battery connector and plug it back. It works for a few seconds and then the problems start again.

The weather in Finland today has been ca. -5 celsius, could it be because of the cold temperature? Could it be because of the low battery charge? I charged both, the car and the controller for the whole last night, about 10 hrs. The car is equipped with GWS fail safe, could it cause the fault somehow?
 

Timmahh

Bajastafarian Madnes
PLUS member
Messages
3,376
Location
Michigan
what radio system are you using?

what your describing is classic glitching, but the ? is whats causing it. A low Batt or a bad cell in it, or just radio interferance from a lesser quality radio system.
 

cyclops1970

Well-Known Member
Messages
628
Location
Hamilton Ontario Canada
what size pack are you running also ? but sounds like the pack needs charging .. also buy a rc volt meter too moniter the levels also it takes battery life out of guessing ..
 

joksu

Member
Messages
8
Location
JKL
The radio system is Hitec Aggressor and the battery pack is a standard pack that came with the car, 5 cell 6V 1500mAh Ni-Cd.

I charged the battery pack again overnight and again, it works ok, at least during a short test without engine running. Have to do a longer test later today.

One more thing I noticed before recharging, when I lose the control on throttle/brake servo, the fail safe activates and turns the T/B-servo to brake position. Correct me if I'm wrong, but should it do this only when the radio signal fails, not when the battery level decreases?

If this really is a battery issue, It's a bit disappointing that the battery only lasts for ca. 30 minutes. Any suggestions for a new battery pack?
 

BullHead

Active Member
Messages
29
Location
Oxelösund
If this really is a battery issue, It's a bit disappointing that the battery only lasts for ca. 30 minutes. Any suggestions for a new battery pack?
Get two battery packs with minimum 2200mAh.
I can run my my MT for about 40 minutes with a 2200mAh,
and I got 3 digital servos. (1x25kg for steering and 2x14kg for throttle and breaks)
 

BullHead

Active Member
Messages
29
Location
Oxelösund
One more thing I noticed before recharging, when I lose the control on throttle/brake servo, the fail safe activates and turns the T/B-servo to brake position. Correct me if I'm wrong, but should it do this only when the radio signal fails, not when the battery level decreases?
Exactly the same thing happens to my Futaba 3PK when battery level drops to much.
You don't wana loose controll over your MT with full throttle!
 

joksu

Member
Messages
8
Location
JKL
I made a test run of about 30 mins with charged battery and no problems. Seems that it is indeed a battery issue, have to start to find a new battery pack.

Thanks for the help guys, one problem solved, waiting for another!

BTW, after first runs with a large scale, I have only one thought in my mind: "WHY did I waste all that time with small scale nitros.." :)
 

Bigger the Better

LSF Plus Member
PLUS member
Messages
7,738
Location
Minnesota
Avatar=:lol:

You say you are charging over night or for 10 hours. I'm guessing your using a small wall charger. If so, my recommendation is for you to get a better charger. If you want your batteries to completely charge, discharge, and peak properly you will need a good charger. You will eventually burn out the battery with the wall charger and if you upgrade to a Nimh battery the wall charger will be incompatible.
If you are charging your receiver batteries I would also recommend getting a AA quick charger for those instead of charging them inside the handset. Most controllers (Not sure about the Hitec Aggressor) are set up for NiCad batteries and cannot take the higher charge that NiMh batteries need for a good charge.
Recommend a good Nimh battery with a high mah for both the receiver and transmitter. You can get the AA's like Duracell rechargeable nimh batteries at any store and the 6V receivers at the hobby store or at one of our online sponsors.
Not sure if the Hitec Aggressor allows the full 6V to the servos (Someone here will know) but if not you will want to run a "Y" lead to your servos for the full capacity of them.
Good luck and ya, I could of bought a few more 1/5's for what I waisted on Nitro.:(
 
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n3il.h

Member
Messages
10
Location
in a house
I mate

I just bought a Aggressor and in the hand book it does say about nicad and nimah batterys so that should be ok...well i hope! cos I cant be bothered taking the batteries in and out all the time to charge them.... also why wouldnt it allow 6v? i don't understand that comment... what does the radio have to do with the output of the battery pack?:)
 

Bigger the Better

LSF Plus Member
PLUS member
Messages
7,738
Location
Minnesota
I am not sure if your type of receiver allows the full battery voltage from the battery to the servo. Mostly it was the older style receivers with BEC that did not allow this. It may not be a issue with the Aggressor receiver? Just may want to check it if no one else chimes in on the subject, it really makes a difference.:)
Here are a couple small photos of the "Y" connection if needed.
 

Attachments

n3il.h

Member
Messages
10
Location
in a house
Hi BTB

Just looking in the manuals spec and it does state

Receiver
-Power Supply: 4.8v-6v

but it also only states 27 and 75mhz where as mine is 40mhz lol

but looks like the 6v is fine :)
 

Bigger the Better

LSF Plus Member
PLUS member
Messages
7,738
Location
Minnesota
All should accept 6.0V its just do they allow 6V to pass through or do they regulate it lower? I will check.:)

EDIT:
Hitec says your system has no BEC installed, anything that is plugged in will go to the servos. No "Y" lead is needed with the Aggressor.

Upgrade your battery and your good to go!
 
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