Pro4 going though batteries quickly

[King James]

My pro4 4600 is going though batteries much quicker than before lately. Not sure why. I haven't changed anything in my setup besides suspension. I'm going though 8 2200s a day. Used to go though about 4-6 depending on how hard I was driving. I just tore it down and it looks good besides being a little dirty. Never had this issue before with my 3300. Could it just be my batteries. They are turnigy nano tech 2200s 45-90c.

[Olle P]

The giveaway should be your motor and ESC's temperatures, although measuring the battery capacity is also an option.
- If the motor gets hotter than normal then there's more friction in the drive train (motor to wheels) than before. Check the bearings, clean and lubricate.
- If the ESC (only) gets hotter than normal then there's a problem with that. With luck it can be fixed (bad capacitor or something like that) but most likely will need a replacement.
- If ESC and motor stay as cool as before the batteries are to blaim.

[dna4engr]

Clarify something for us. When you say 4-6 a day, that was with the 4600 or the 3300? You said same setup, but then you mentioned a 3300.

I've found pro4 motors to be very power hungry compared to redlines or roc412. Olle made some very good suggestions to try. My gut Would say batteries, but check everything. I assume you're always balance charging on a moderate charge rate (2.2 amps for the 2200 batteries). Also, the fact you're running nanotech is an indication it might be the batts. Do you have another brand or a buddy that you could borrow one from to compare. Not picking on turnigy, I have many myself, just have read many problems with nanotech models.

Dna

[JohnRobHolmes]

Battery, especially if they are running hotter, have more than 30 cycles, or if the weather is colder.

[King James]

Originally Posted by Olle P

The giveaway should be your motor and ESC's temperatures, although measuring the battery capacity is also an option.
- If the motor gets hotter than normal then there's more friction in the drive train (motor to wheels) than before. Check the bearings, clean and lubricate.
- If the ESC (only) gets hotter than normal then there's a problem with that. With luck it can be fixed (bad capacitor or something like that) but most likely will need a replacement.
- If ESC and motor stay as cool as before the batteries are to blaim.

Motor and esc are warm. But not hot, I'm running 11/56 gearing so the motor doesn't get hot. Esc was in a tight space so I'm gonna relocate it to get it more air flow.

[King James]

Originally Posted by dna4engr

Clarify something for us. When you say 4-6 a day, that was with the 4600 or the 3300? You said same setup, but then you mentioned a 3300.

I've found pro4 motors to be very power hungry compared to redlines or roc412. Olle made some very good suggestions to try. My gut Would say batteries, but check everything. I assume you're always balance charging on a moderate charge rate (2.2 amps for the 2200 batteries). Also, the fact you're running nanotech is an indication it might be the batts. Do you have another brand or a buddy that you could borrow one from to compare. Not picking on turnigy, I have many myself, just have read many problems with nanotech models.

Dna

With the 4600 I bought in January. I ran the 3300 last year. Our group usually crawls from 10-1. Takes a lunch break then crawls 2-5. Yeah I balance charged them every time. I'll have to check and see if anyone else had a different brand I could try. Most of us do use the turnigy.

[King James]

Originally Posted by JohnRobHolmes

Battery, especially if they are running hotter, have more than 30 cycles, or if the weather is colder.

Weather is definitely cooler, but I bought the batteries back in January and they may have 15-20 cycles on them. I'm gonna clean out the motor with compressed air tonight. I tore it down and it was very dusty/dirty.

[JohnRobHolmes]

Dust won't affect motor efficiency. I bet you are driving harder and the packs are wearing out. You probably have 85 to 90% usable capacity on discharge, high power motors wear small packs quickly.

[King James]

Ok, I'll look into some new packs

[dna4engr]

Try the Turnigy "Heavy Duty" packs. These are not the nanotech models. Had good luck so far. Also, can you fit a bigger Mah in there? Power hungry motor will obviously last longer.

Dna

[King James]

Yeah I can fit bigger now When I bought them I needed something small.

[Olle P]

Originally Posted by JohnRobHolmes

Dust won't affect motor efficiency. ...

A matter of definition. With lots of dust and grime in the motor bearings the load on the axle will increase and the output efficiency go down.

The mentioning of dust in my previous post include all bearings in the drive line and any dust in gearboxes and such, all of which can add friction.

[JohnRobHolmes]

Sure, if the bearings are full of dust or otherwise damaged it will reduce system efficiency. If there is enough to make a noticeable difference in runtime, the bearings would be consuming so much energy that the bearing grease would catch on fire (if localized in motor bearings) and/or the motor and ESC would be running at a higher temperature. As a whole system it is more likely than just being in the motor bearings, but to the order of using twice the amount of energy I would say bearings are probably not the root issue since he reports no meaningful change in system heat. But certainly a very good point and something to look over and clean, 10 watts gained is a lot in terms of runtime on a 2200 pack.