Alright guys, I'm scratching my head trying to figure this one out. Our radio JR Z1and Z01B was running fine last weekend for a club race, and this weekend, we go to start a series race, and we chased an electrial problem the whole day. Whats happening is the battery is not lsting more than a few minutes. during warm up on the pit wall, I noticed alittle more twitching than normal, and I didn;t even make 1 warm up lap until the battery went dead.
the battery was charged probably 2 hours prior to the practice. So next we grab the back up battery, both were re charged at the same time, and same result, one lap, and battery was dead.We ended up chasing this the hole day, I've changed both servos, by passed the switch, disconnected the transponder, completely switched radio's from the JR to 3PK, and same results, I even used a different charger thinking mabye our charger was't working right, anybody got any ideas?

Assume this is NiMh? Are they getting hot when you charge them? If they are and going flat like that, have you tried a diff batt in your car, like borrow one and try? Motor is biggest draw on the batt, suspect batts are going, if not then they're not getting charged. Have you tried running your batts in someone else's car?

Yep we had someone else charge one of our batterys, same thing, then got some one elses NM, and still same thing,

You have a bad cell or two in the pack,or a bad connection somewere in the pack.If they are side by side cells check the solder connections.

If it does the same thing on some else's pacs, then its gotta be something on your rig. From what you've described, you've checked everything except the motor.

Def ck all connections - if its a bad connection(s), they should be getting pretty hot to suck so much jusice up, should be obvious.

what motor are you taliking about?, were running nitro, I am going to take all the electronics and put it in one of our ther cars, and see what happens. The first battery pak could have a bad cell, its about 3 months old, the other is new, I gues it could be coincendence both paks are bad, the battery pak does get warm faster than normal, and I'm gonna put an in-line amp meter, and look at the current draw when the servos are activated, hopefully I'll see some excessive draw, Im also gonna go throught he connections

Sorry, my bad, didn't see the Z01B.

Has to be something simple, there are only a few components involved. Make sure a wire is not shorted somewhere where it rubs chassis or something like that that could dump the batt.

In order for any battery to be discharged in a few minutes of use it must be discharged at a 20-30C rate. Not many rx batts, wires, plugs, ect. can handle that current. I would look into the "batteries not being charged" first. If the batt is indeed getting charged, then please test it after it is full.

it appears that the NM batterys that I had at the track had decided to crap out all at the same time, 3 different ones. last night i charged up a pak form one of the other cars for about 30 minutes, and with servos and transponder, and inline amp meter it lasted more than 5 minutes, I turned it off at that time and no indications of it going down. I then recharged the ones we had at the track, they lasted any where from 15 secs to 60 secs.
Thats sabout all I can think of,coincidence? don't know, well be back out this weekend with a new battery pak and see what happens

When you recharged the suspect pacs, you should be able to notice some cells getting hotter than others - usually when cells go bad, they get real hot when charging.

That is a strange coincidence to have them go at same time though.

OK I took one of the suspect battery paks and got one of the cheap ofna chargers that charge at 100ma, and let it charge for 2 hours. I plugged it in, and simulated driving the car, servos connected, granted I realize the load on the servos will not get the same load as driving, but watching the trandsponder LED, the system ran for 8 plus minutes, and no flickering on the transponder LED. I normally use a Trinton Jr. charger, and usually I charge at 1 amp, the NM are 1600ma, so I changed it to .5 ma and charged the other suspect pak, this took about an hour to charge up, I then waited about 15 minutes, and plugged it into the buggy, same servos etc, and this set up lasted 8 minutes, no problems. The only difference from at the track is that I usually have been chargeing at 1 amp, I've been doing this for a few years, now is it possible that the charger not charge properly at 1 amp but OK at 1/2 amp? I wouldn't think so, I'm gonna try everything again but drive it, but has anybody ran into this ? I'm gonna replace the charger, but I did have a guy peak chage the battery at the track, and it only took 3 minutes to peak it off, and died after 2 minutes. I'm getting to the point of just replacing the batteries and charger, but is this making any sence?

this probably a case of a worn/old battery giving a peak charger fits because of voltage fluctuations. The charger is not faulty, it is doing what it is supposed to do. It is a matter of "those batteries on those chargers"

At 0.5amps for 60min, you're only putting in 500mah and not all of what is input winds up in capacity due to losses. That's not getting close to capacity when it peaks.

Charging at lower rates there is not as much voltage fluctuation which may be seen as a peak by your charger. Try charging at 0.5amps and if you don't get a highcapacity (mah) input, re-peak it a few times and see what the amount going in on repeak does. Does your 610c have a trickle option following a peak charge? You could use that to be sure they're topped off. When mine start getting old, I use a wall plugin charger and let them go overnite and then re-peak them on the charger before using.

Either that or start letting them charge at some low rate like 0.1amp for 14-16hrs. If you can't tolerate the time spent charging, its prob time for new ones.

Many chargers have a "lock out" or "peak delay at start" function that can help get over the first hump so to speak (if there is a first hump) The nicest thing would be to watch the voltage during charge and see if it indeed goes down before it is full. If it does then the charger is doing what it supposed to.

thanks guys I'll follow up tomorrow, I'm gonna charge the batteries at .500 ma and run the buggy, and pay attention to the voltages, the other thing that I may have done wrong was not let the battery cool down after the practice, and when they started to act up I was in a hurry for the qualifier, it was 108 that day outside, so that could have something to do with it