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Discussion Starter #1
Hey, I've been having a problem lately while discharging or cycling batteries. I have my amp rate set at 20amps, but some of the batteries i hook up will only reach something like 19.2amps...some of the batteries do reach 20amps. This leads me to believe there is a problem with some of the batteries and not the charger. Has anyone else heard of or had this happen to them and what do you think I can do about it? Is there a way to "fix" the batteries if they are indeed the problem? Thanks in advance.

Shawn
 

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Discussion Starter #3
I also forgot to mention that when I do discharge packs, the positive lead going from charger to battery gets extremely hot, as in it has melted off the rubber boot from the alligator clip. I know it will get hot just from the load going through it, but I really don't think it should be getting that hot. The packs never get really hot though, just like normal discharge temp.

Shawn
 

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I've got a Turbo 35 GFX like that. I sent it back and it worked fine for them. Still does it sometimes for me.

Unless it does it (not reach the amperage setting) every time you discharge a battery you are not going to get it fixed. They will test it once or twice, see that it works properly that once or twice and send it back to you.
 

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Discussion Starter #5
Thanks for the notice guys. I may contact them still and send them a battery i know does it along with the charger....we will see though since race season is starting I don't know how i'll get along without a charger.

Shawn
 

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Had the EXACT thing, mine max'd @ 23 amps, sent it in for service, they "Reset" the unit, in the paperwork they said hold the left arrow when powering the unit up and it will do it. I was impressed they were so honest and modest in their billing and the time it took to return the unit, but hopefully no need to do it.
Tom
 

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Check your connections first !!!

The alligator set up is only so-so ,built for the average racer , replace the last 6 inches of the voltage sensing wire with a good quality 16-18 gauge silicone high flex wire and re - solder the alligator clip.

If this doesn't help ,,, its probably in the power supply !
Alot of racers try and run this unit off a smaller than recommended unit or the power supply is faulty at 80-100 % output as the GFX needs sufficient amperage to run the discharge mosfets.

BEEN THERE , DONE THAT , TOOK MY 25 AMP UNIT BACK TO R S , WHICH THEY SAID HAD NO PROBLEMS , GOT A REPLACEMENT AND PROBLEM FIXED, I CAN DISCHARGE UP TO MY MAX OF 35 AMPS.
 

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The info about the power supply is very interesting but the question remains, with the same power supply, why does it only do it sometimes and not all the time? At any given setting from 17A to 35 A, every now and then it will fail to reach the discharge amperage setting.
 

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Your power supply has an intermittent problem of not producing enough amps.

Hitch it up to a good car battery and see if your problem goes away .

When you buy a power supply , check what the contiuous amperage / voltage is , not just the peak , advertising at its worst , some units are only rated at 80-90 % of rated output. Its called the duty cycle.
 

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I can't believe that... I used to discharge at 30 amps and I only had a 15 amp PS at the time. I sold the PS so I cant go and try it now to prove my memory isn't bad..lol
I think you have a problem with your connection to the pack... especially if the clip is getting that hot for a 20 amp discharge!
Always try the "reset" trick mentioned above before you send it in.
 

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I don;t know about RcOvalGuy, but I ahve daens plugs on my T35 GFX and it still doesn't reach the discharge amp setting every now and then. The deans plugs are not getting hot.
 

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Discussion Starter #12
You guys have given me many good ideas to try out. I never knew about the reset trick, and I did just recieve a new power supply so I will try that as well, only one thing at a time though so I can try and figure out what the real problem is...Thanks all. I will post again next time I get to it with results and what I found.

Shawn
 

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Happened to email Jim at CE today and mentioned your problem,,, this is what he wrote back to me

"if the clip gets hot it is a poor connection, usually a bad solder joint. The fact that the unit did not lock in on the set discharge rate also points to a faulty connection.
The GFX consumes very little (maybe 1/10 of an amp) from the power supply during discharge, it all comes from the battery pack"
 

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Try the car battery

I still lean towards the power supply as it could have a bad mosfet or diode and allowing an AC ripple at ANY amp draw.

It fixed mine :thumbsup:
 

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Your power supply amp rating, has nothing to do with the discharge function on your charger.. I ran my t 35 off of a 10 amp power supply for many years.. i never had any issues with improper discharging.. The power supply rating has to do with the set amp charge, ie you can not charge at a higher amp then your power supply.. and also the motor function.. your motor can not draw more amps then your power supply..

If you having problems with the discharge funtion it is another issue then the power supply..It states rght in the manual about PS ratings.. Ive notice some batteries if there bad, they wont allow a higher discharge.. the battery just isnt capable of supplying the power.. usually means the pack is close to toast..

if your clip has melted off of the wire, dont just solder it back on, replace it.. Ive seen clips go bad.. i usually replaced mine once a year..

Also for changing the wire on the chargers.. If you change the length, or the quality of wire your readings will change as well.. the chargers are all calibrated with the right length to get consistent readings from charger to charger.. I use to have a t 30 that i changed the wires on.. I Had the charger all painted up, and put neon wires on it.. same length and all.. the charger never read the same again..

i suggest before making any changes to contact CE and ask them.. there also very good about fixing chargers for free or reasonable prices. They guarentee longer if the chargers are used as they come..
 

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Sorry to play devils advocate ,,, but the voltage sensing wire length is BS and I've spoken to tech service many times and they endorced the change to a high flex silicone wire.

Plus if you read my comment I said to change the last 6 inches of wire not add 6 inches !

the voltage sensing wire has NO current going thu it so the minute resistance in wire length is hardly noticeable.

I've never heard back from the thread starter if he tryed it on a car battery.

So much information , so much misled help :eek:
 

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NCFRC said:
Sorry to play devils advocate ,,, but the voltage sensing wire length is BS and I've spoken to tech service many times and they endorced the change to a high flex silicone wire.

Plus if you read my comment I said to change the last 6 inches of wire not add 6 inches !

the voltage sensing wire has NO current going thu it so the minute resistance in wire length is hardly noticeable.

I've never heard back from the thread starter if he tryed it on a car battery.

So much information , so much misled help :eek:
Here is a simple test for you to show it does matter on lenghth.. take the voltage leads, and put them right on the battery bar.. hit discharge till it hits the cut off..

Then take the clips, and hook them as close as you can to the cap of the battery.. it takes a little bit to get them to stick right.. hit discharge again.. You should get about 10 extra seconds of discharge out of the pack having the sensors closer to the battery.... Its the same with the type and length of wire.. I wasnt saying it wont work or wont read.. but if your use to certain readings, they will change from what they were.. Ive also noticed a diffrence in voltage and internal resistance by messing with wire length..

The owner of CE races at my local trackin Milwaukee.... I was there the day a buddy of mine ask him about the wires. He asked bacause he wanted to put colored wires on... It does affect the numbers..
 

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The Competition Electronics GFX is probably the best tool anyone into RC racing could ever buy , I love mine , but we all have to remember it's NOT laboratory grade test equipment, its darn close , but if it was it would be in the thousands not in the hundreds.

A VERY GOOD BANG FOR YOUR BUCK :thumbsup:
 
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