HK-450GT CCPM Alloy T-Rex compatible - Part IV
01-12-2014, 04:27 PM
#1351
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Howdy,
well I managed to fly my 500, the quad and the axn yesterday so it was an interesting day. Did a quad speed run in dead calm as well for the speed challenge Results are:
21.25 (metres per second) = 76.5 km
Here's the first flight on the 500 for months so I was taking it very easy.
Both my last 2 nanotech 2650mah 6s packs have dropped the same cell as the first 2 did. So I have no packs no. All 4 packs have done the same thing. Won't buy nanotech packs again. Even though i've had a good run out of the 2200 3s nanotech's.
http://www.youtube.com/watch?v=FW8_WTIn9Ag
well I managed to fly my 500, the quad and the axn yesterday so it was an interesting day. Did a quad speed run in dead calm as well for the speed challenge Results are:
21.25 (metres per second) = 76.5 km
Here's the first flight on the 500 for months so I was taking it very easy.
Both my last 2 nanotech 2650mah 6s packs have dropped the same cell as the first 2 did. So I have no packs no. All 4 packs have done the same thing. Won't buy nanotech packs again. Even though i've had a good run out of the 2200 3s nanotech's.
http://www.youtube.com/watch?v=FW8_WTIn9Ag
01-12-2014, 04:31 PM
#1352
Join Date: Dec 2007
Location: Zellwood, FL
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Howdy,
well I managed to fly my 500, the quad and the axn yesterday so it was an interesting day. Did a quad speed run in dead calm as well for the speed challenge Results are:
21.25 (metres per second) = 76.5 km
Here's the first flight on the 500 for months so I was taking it very easy.
Both my last 2 nanotech 2650mah 6s packs have dropped the same cell as the first 2 did. So I have no packs no. All 4 packs have done the same thing. Won't buy nanotech packs again. Even though i've had a good run out of the 2200 3s nanotech's.
well I managed to fly my 500, the quad and the axn yesterday so it was an interesting day. Did a quad speed run in dead calm as well for the speed challenge Results are:
21.25 (metres per second) = 76.5 km
Here's the first flight on the 500 for months so I was taking it very easy.
Both my last 2 nanotech 2650mah 6s packs have dropped the same cell as the first 2 did. So I have no packs no. All 4 packs have done the same thing. Won't buy nanotech packs again. Even though i've had a good run out of the 2200 3s nanotech's.
Grrrrr (in red) and the *****es are EXPENSIVE!
Glad you got out and about!
b
01-12-2014, 05:07 PM
#1353
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Location: Ingleburn, AUSTRALIA
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Howdy,
well I managed to fly my 500, the quad and the axn yesterday so it was an interesting day. Did a quad speed run in dead calm as well for the speed challenge Results are:
21.25 (metres per second) = 76.5 km
Here's the first flight on the 500 for months so I was taking it very easy.
Both my last 2 nanotech 2650mah 6s packs have dropped the same cell as the first 2 did. So I have no packs no. All 4 packs have done the same thing. Won't buy nanotech packs again. Even though i've had a good run out of the 2200 3s nanotech's.
well I managed to fly my 500, the quad and the axn yesterday so it was an interesting day. Did a quad speed run in dead calm as well for the speed challenge Results are:
21.25 (metres per second) = 76.5 km
Here's the first flight on the 500 for months so I was taking it very easy.
Both my last 2 nanotech 2650mah 6s packs have dropped the same cell as the first 2 did. So I have no packs no. All 4 packs have done the same thing. Won't buy nanotech packs again. Even though i've had a good run out of the 2200 3s nanotech's.
They should be pretty similar results seeing we have the same setup. Im sure there is something in the settings to change to get more speed as Im sure with the KK board on mine used to go much quicker.
After talking to some guys at the field yesterday who use Nanotechs (5000 6s), together with your 4 bad ones and my dead one and a couple that are starting to puff, Im steering clear of them.
Never had a problem with the normal Turnigys and they are over 2 years old.
They might be ok for people with Brian money
who can afford to replace them every 50 cycles.
01-12-2014, 09:26 PM
#1354
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Howdy,
well I managed to fly my 500, the quad and the axn yesterday so it was an interesting day. Did a quad speed run in dead calm as well for the speed challenge Results are:
21.25 (metres per second) = 76.5 km
Here's the first flight on the 500 for months so I was taking it very easy.
Both my last 2 nanotech 2650mah 6s packs have dropped the same cell as the first 2 did. So I have no packs no. All 4 packs have done the same thing. Won't buy nanotech packs again. Even though i've had a good run out of the 2200 3s nanotech's.
http://www.youtube.com/watch?v=FW8_WTIn9Ag
well I managed to fly my 500, the quad and the axn yesterday so it was an interesting day. Did a quad speed run in dead calm as well for the speed challenge Results are:
21.25 (metres per second) = 76.5 km
Here's the first flight on the 500 for months so I was taking it very easy.
Both my last 2 nanotech 2650mah 6s packs have dropped the same cell as the first 2 did. So I have no packs no. All 4 packs have done the same thing. Won't buy nanotech packs again. Even though i've had a good run out of the 2200 3s nanotech's.
http://www.youtube.com/watch?v=FW8_WTIn9Ag
I'm a bit skeptical of the issue you're describing here... 4 packs, likely of different production runs, all fail on the same cell? I'm thinking the balancer portion of your charger may not be properly charging that cell. I'd ESPECIALLY suspect that if it is on a #4, #5 0r #6 cell that isn't used with 3S packs.
Otherwise -
If you're doing the Q450 quads, HK has the V3 Integrated Power Distribution version frames on The Swarm right now for $8.73 apiece; you can get 3 of them at that price, so good opportunity to stock up on spare arms cheap.
http://www.hobbyking.com/hobbyking/s...B-2F0F1BC8F952
Remember to sign into to HK first, yadda, yadda, and if the link doesn't work, here's The Swarm so you can search it yourself:
http://hk.rc-international.info/swarm
l8ters ffolkks!
mnem
Roundy-plop for teh win.
Last edited by mnemennth; 01-12-2014 at 09:29 PM.
01-12-2014, 09:44 PM
#1355
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Jonesey...
I'm a bit skeptical of the issue you're describing here... 4 packs, likely of different production runs, all fail on the same cell? I'm thinking the balancer portion of your charger may not be properly charging that cell. I'd ESPECIALLY suspect that if it is on a #4, #5 0r #6 cell that isn't used with 3S packs.
I'm a bit skeptical of the issue you're describing here... 4 packs, likely of different production runs, all fail on the same cell? I'm thinking the balancer portion of your charger may not be properly charging that cell. I'd ESPECIALLY suspect that if it is on a #4, #5 0r #6 cell that isn't used with 3S packs.
After flying the 6s packs for a couple of mins, I've got one cell on 3.4v and the rest on 3.9. It's always cell number 6. The 4 packs were purchased in two's about 3 months apart. Strange indeed. It's either draining this cell faster or infact it has not balanced it properly.
EDIT: further to this after doing a bit of reading. I think the correct term for what is going on with my nano's is "voltage sag" on one cell. Which pretty much makes them useless. I'm not sure if it's my fault for not using them enough. Another thing I read about is the nanos have a very steep drop off and if you go over this it can damage the cells. Maby this has happened, not sure. They have been stored at storage charge 3.8v/cell when I wasn't using them.
I'm half considering selling my 500 as I'd rather buy packs for the quad or put it into another project then having to buy more 6s packs.
Last edited by ahamay; 01-12-2014 at 10:22 PM. Reason: No reason you need to know about.
01-13-2014, 04:14 AM
#1356
Join Date: Dec 2007
Location: Zellwood, FL
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Jonesey...
I'm a bit skeptical of the issue you're describing here... 4 packs, likely of different production runs, all fail on the same cell? I'm thinking the balancer portion of your charger may not be properly charging that cell. I'd ESPECIALLY suspect that if it is on a #4, #5 0r #6 cell that isn't used with 3S packs.
Otherwise -
If you're doing the Q450 quads, HK has the V3 Integrated Power Distribution version frames on The Swarm right now for $8.73 apiece; you can get 3 of them at that price, so good opportunity to stock up on spare arms cheap.
http://www.hobbyking.com/hobbyking/s...B-2F0F1BC8F952
Remember to sign into to HK first, yadda, yadda, and if the link doesn't work, here's The Swarm so you can search it yourself:
http://hk.rc-international.info/swarm
l8ters ffolkks!
mnem
Roundy-plop for teh win.
I'm a bit skeptical of the issue you're describing here... 4 packs, likely of different production runs, all fail on the same cell? I'm thinking the balancer portion of your charger may not be properly charging that cell. I'd ESPECIALLY suspect that if it is on a #4, #5 0r #6 cell that isn't used with 3S packs.
Otherwise -
If you're doing the Q450 quads, HK has the V3 Integrated Power Distribution version frames on The Swarm right now for $8.73 apiece; you can get 3 of them at that price, so good opportunity to stock up on spare arms cheap.
http://www.hobbyking.com/hobbyking/s...B-2F0F1BC8F952
Remember to sign into to HK first, yadda, yadda, and if the link doesn't work, here's The Swarm so you can search it yourself:
http://hk.rc-international.info/swarm
l8ters ffolkks!
mnem
Roundy-plop for teh win.
I always appreciate your posts! I'm prolly going to be moving away from this 450 platform as things are getting a little "tight" on my frame!
All the best!
b
01-13-2014, 04:19 AM
#1357
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I'll look into that. I do use a different charger for the 6s packs. But they seem to balance up fine (according to the charger) and I also check every pack before I fly it with a cell alarm/checker. What does not make sense is I used this charger only when I first got the 6s packs and had no issues. Worth checking though.
After flying the 6s packs for a couple of mins, I've got one cell on 3.4v and the rest on 3.9. It's always cell number 6. The 4 packs were purchased in two's about 3 months apart. Strange indeed. It's either draining this cell faster or infact it has not balanced it properly.
EDIT: further to this after doing a bit of reading. I think the correct term for what is going on with my nano's is "voltage sag" on one cell. Which pretty much makes them useless. I'm not sure if it's my fault for not using them enough. Another thing I read about is the nanos have a very steep drop off and if you go over this it can damage the cells. Maby this has happened, not sure. They have been stored at storage charge 3.8v/cell when I wasn't using them.
I'm half considering selling my 500 as I'd rather buy packs for the quad or put it into another project then having to buy more 6s packs.
After flying the 6s packs for a couple of mins, I've got one cell on 3.4v and the rest on 3.9. It's always cell number 6. The 4 packs were purchased in two's about 3 months apart. Strange indeed. It's either draining this cell faster or infact it has not balanced it properly.
EDIT: further to this after doing a bit of reading. I think the correct term for what is going on with my nano's is "voltage sag" on one cell. Which pretty much makes them useless. I'm not sure if it's my fault for not using them enough. Another thing I read about is the nanos have a very steep drop off and if you go over this it can damage the cells. Maby this has happened, not sure. They have been stored at storage charge 3.8v/cell when I wasn't using them.
I'm half considering selling my 500 as I'd rather buy packs for the quad or put it into another project then having to buy more 6s packs.
Yah, that HAS to be frustrating!
I've been using the Turnigy versions forever and have great luck!
Toyed around with selling my 500 too but I won't get near what I paid for it and for now I like going to the field and "mixing it up" with the Heli, Quad and planks!
I used to keep 5 or 6 batteries for it but now I'm down to two or three and will leave it that way!
Clear skies!
b
01-13-2014, 04:55 AM
#1358
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Hiya Jonesy!
Yah, that HAS to be frustrating!
I've been using the Turnigy versions forever and have great luck!
Toyed around with selling my 500 too but I won't get near what I paid for it and for now I like going to the field and "mixing it up" with the Heli, Quad and planks!
I used to keep 5 or 6 batteries for it but now I'm down to two or three and will leave it that way!
Clear skies!
b
Yah, that HAS to be frustrating!
I've been using the Turnigy versions forever and have great luck!
Toyed around with selling my 500 too but I won't get near what I paid for it and for now I like going to the field and "mixing it up" with the Heli, Quad and planks!
I used to keep 5 or 6 batteries for it but now I'm down to two or three and will leave it that way!
Clear skies!
b
I've just sussed out some turnigy 3000 6s packs for around 50 bucks each delivered. I think I'll just get two of those and call it a day.
01-13-2014, 03:45 PM
#1359
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Jonesy -
Uggh. That's NOT cool. I'm going to recommend a couple things;
First -
Get in the habit of balance charging and CHECKING the per-cell voltage after the charge completes EVERY TIME. And then after use, before you recharge, check them with a stand-alone balancer like the one below and balance the pack BEFORE RECHARGING if any cell is more than .05V away from the others. The balancing circuit in a modern LiPo charger can only make up for SO MUCH of an imbalance; they only have a certain amount of time before the pack reaches delta peak. Balancing a pack that's as far out as yours can take hours.
Second -
Make double damn sure your charger is doing its job; charge your new batteries, then discharge them using a dummy load, NOT the "discharge cycle" in the charger. For my 3S packs, I use a single 60W headlight bulb; for 6S, use 2 in series. You need to monitor them with a battery tester like this one:
http://www.hobbyking.com/hobbyking/s...dproduct=34137
which will sound an alarm if the connected battery becomes imbalanced, as well as a regular battery minder like this one:
http://www.hobbyking.com/hobbyking/s...rm_2s_6s_.html
to tell you when the battery is done discharging. If you get through the discharge cycle on a new pack and all cells are within .1 volt under load, your charger is PROBABLY working properly. If not, the balance circuit is probably compromised. This tester is the one I have; it will alarm if battery balance goes more than .04V off on any cell, which is good for an unloaded battery. It will probably go off on one or more cells with the battery under load when the battery nears 3.3V per cell; this is normal.
There is an array of transistors and resistors in the balance circuit; those transistors can develop a leaky junction or even short out as a result of voltage spikes caused by sparks when connecting/disconnecting a pack, or even from a brand new pack with very low internal resistance drawing too much current from the balancing circuit. The worst part is, this can happen and the charger APPEARS to work normally; voltages appear normal at the end of the charge, and the only way of knowing is that batteries start to fail repeatedly in the same way.
I had a brand-new 4S 25-50C rated Nano-Tech kill my iMars charger this way; the internal resistance on it measured like 5 milli-ohms! I found after the first charge with that battery that subsequent charges never charged accurately on 2 cells; it had actually drawn enough current through the balance circuit to kill 2 of the inputs on the voltage monitor D-A converter. After that, I never charge at more than 2 amps on that pack; though I have charged as high as 6A on my 3S packs.
Right now, I'm in the process of rebuilding one of these:
http://www.hobbypartz.com/75p-t6-multi-charger.html
that I picked up off eBay for $17; the one channel that appeared to work seemed to charge normally to an even 4.20V/cell; it even tested right with my Power Analyzer. I would never have known there was something wrong with it if it weren't for the fact I left a battery connected which I had observed charge up evenly to approx 4.19V per cell just before I sat down to watch TV with wifey for a few hours; when I went to disconnect it, I found one cell had dropped to 3.9V. A little testing revealed it had a shorted transistor (about the size of a grease ant) in the balance array on that channel.
My point is this; if you're not checking the cell balance of your batteries EVERY TIME you charge (I do), one of your batteries could have damaged that cell of the balance array on both your chargers and you'd never know.
Too bad you're so far away; I'd be glad to charge your packs on one of my known-good chargers and give them a dummy-load workout... I'm not afraid of your batteries damaging my charger since I can fix it if they do anyways.
Actually... if you have a friend nearby who'd let you charge your batteries on their charger, the chance of harming a charger with a faulty battery is very small if you charge at 1A or so; I'd suggest you balance the packs, then try charging on another charger, and then double-check the voltage per cell with a power analyzer like the one I link above.
mnem
*adrift*
Uggh. That's NOT cool. I'm going to recommend a couple things;
First -
Get in the habit of balance charging and CHECKING the per-cell voltage after the charge completes EVERY TIME. And then after use, before you recharge, check them with a stand-alone balancer like the one below and balance the pack BEFORE RECHARGING if any cell is more than .05V away from the others. The balancing circuit in a modern LiPo charger can only make up for SO MUCH of an imbalance; they only have a certain amount of time before the pack reaches delta peak. Balancing a pack that's as far out as yours can take hours.
Second -
Make double damn sure your charger is doing its job; charge your new batteries, then discharge them using a dummy load, NOT the "discharge cycle" in the charger. For my 3S packs, I use a single 60W headlight bulb; for 6S, use 2 in series. You need to monitor them with a battery tester like this one:
http://www.hobbyking.com/hobbyking/s...dproduct=34137
which will sound an alarm if the connected battery becomes imbalanced, as well as a regular battery minder like this one:
http://www.hobbyking.com/hobbyking/s...rm_2s_6s_.html
to tell you when the battery is done discharging. If you get through the discharge cycle on a new pack and all cells are within .1 volt under load, your charger is PROBABLY working properly. If not, the balance circuit is probably compromised. This tester is the one I have; it will alarm if battery balance goes more than .04V off on any cell, which is good for an unloaded battery. It will probably go off on one or more cells with the battery under load when the battery nears 3.3V per cell; this is normal.
There is an array of transistors and resistors in the balance circuit; those transistors can develop a leaky junction or even short out as a result of voltage spikes caused by sparks when connecting/disconnecting a pack, or even from a brand new pack with very low internal resistance drawing too much current from the balancing circuit. The worst part is, this can happen and the charger APPEARS to work normally; voltages appear normal at the end of the charge, and the only way of knowing is that batteries start to fail repeatedly in the same way.
I had a brand-new 4S 25-50C rated Nano-Tech kill my iMars charger this way; the internal resistance on it measured like 5 milli-ohms! I found after the first charge with that battery that subsequent charges never charged accurately on 2 cells; it had actually drawn enough current through the balance circuit to kill 2 of the inputs on the voltage monitor D-A converter. After that, I never charge at more than 2 amps on that pack; though I have charged as high as 6A on my 3S packs.
Right now, I'm in the process of rebuilding one of these:
http://www.hobbypartz.com/75p-t6-multi-charger.html
that I picked up off eBay for $17; the one channel that appeared to work seemed to charge normally to an even 4.20V/cell; it even tested right with my Power Analyzer. I would never have known there was something wrong with it if it weren't for the fact I left a battery connected which I had observed charge up evenly to approx 4.19V per cell just before I sat down to watch TV with wifey for a few hours; when I went to disconnect it, I found one cell had dropped to 3.9V. A little testing revealed it had a shorted transistor (about the size of a grease ant) in the balance array on that channel.
My point is this; if you're not checking the cell balance of your batteries EVERY TIME you charge (I do), one of your batteries could have damaged that cell of the balance array on both your chargers and you'd never know.
Too bad you're so far away; I'd be glad to charge your packs on one of my known-good chargers and give them a dummy-load workout... I'm not afraid of your batteries damaging my charger since I can fix it if they do anyways.
Actually... if you have a friend nearby who'd let you charge your batteries on their charger, the chance of harming a charger with a faulty battery is very small if you charge at 1A or so; I'd suggest you balance the packs, then try charging on another charger, and then double-check the voltage per cell with a power analyzer like the one I link above.
mnem
*adrift*
Last edited by mnemennth; 01-13-2014 at 04:14 PM. Reason: unBALANCED-ED
01-13-2014, 04:50 PM
#1361
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Hey!
I have a similar thing I made to have a servicing stand for flat-screen TVs. Sick minds think alike!
mnem
Cold pizza... check. Warm beer... check... Hangover of he millennium... check. Add a fistful of Motrin and Tylenol: The breakfast of Champions!
I have a similar thing I made to have a servicing stand for flat-screen TVs. Sick minds think alike!
mnem
Cold pizza... check. Warm beer... check... Hangover of he millennium... check. Add a fistful of Motrin and Tylenol: The breakfast of Champions!
01-13-2014, 04:56 PM
#1362
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Location: Zellwood, FL
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Jonesy -
Uggh. That's NOT cool. I'm going to recommend a couple things;
First -
Get in the habit of balance charging and CHECKING the per-cell voltage after the charge completes EVERY TIME. And then after use, before you recharge, check them with a stand-alone balancer like the one below and balance the pack BEFORE RECHARGING if any cell is more than .05V away from the others. The balancing circuit in a modern LiPo charger can only make up for SO MUCH of an imbalance; they only have a certain amount of time before the pack reaches delta peak. Balancing a pack that's as far out as yours can take hours.
Second -
Make double damn sure your charger is doing its job; charge your new batteries, then discharge them using a dummy load, NOT the "discharge cycle" in the charger. For my 3S packs, I use a single 60W headlight bulb; for 6S, use 2 in series. You need to monitor them with a battery tester like this one:
http://www.hobbyking.com/hobbyking/s...dproduct=34137
which will sound an alarm if the connected battery becomes imbalanced, as well as a regular battery minder like this one:
http://www.hobbyking.com/hobbyking/s...rm_2s_6s_.html
to tell you when the battery is done discharging. If you get through the discharge cycle on a new pack and all cells are within .1 volt under load, your charger is PROBABLY working properly. If not, the balance circuit is probably compromised. This tester is the one I have; it will alarm if battery balance goes more than .04V off on any cell, which is good for an unloaded battery. It will probably go off on one or more cells with the battery under load when the battery nears 3.3V per cell; this is normal.
There is an array of transistors and resistors in the balance circuit; those transistors can develop a leaky junction or even short out as a result of voltage spikes caused by sparks when connecting/disconnecting a pack, or even from a brand new pack with very low internal resistance drawing too much current from the balancing circuit. The worst part is, this can happen and the charger APPEARS to work normally; voltages appear normal at the end of the charge, and the only way of knowing is that batteries start to fail repeatedly in the same way.
I had a brand-new 4S 25-50C rated Nano-Tech kill my iMars charger this way; the internal resistance on it measured like 5 milli-ohms! I found after the first charge with that battery that subsequent charges never charged accurately on 2 cells; it had actually drawn enough current through the balance circuit to kill 2 of the inputs on the voltage monitor D-A converter. After that, I never charge at more than 2 amps on that pack; though I have charged as high as 6A on my 3S packs.
Right now, I'm in the process of rebuilding one of these:
http://www.hobbypartz.com/75p-t6-multi-charger.html
that I picked up off eBay for $17; the one channel that appeared to work seemed to charge normally to an even 4.20V/cell; it even tested right with my Power Analyzer. I would never have known there was something wrong with it if it weren't for the fact I left a battery connected which I had observed charge up evenly to approx 4.19V per cell just before I sat down to watch TV with wifey for a few hours; when I went to disconnect it, I found one cell had dropped to 3.9V. A little testing revealed it had a shorted transistor (about the size of a grease ant) in the balance array on that channel.
My point is this; if you're not checking the cell balance of your batteries EVERY TIME you charge (I do), one of your batteries could have damaged that cell of the balance array on both your chargers and you'd never know.
Too bad you're so far away; I'd be glad to charge your packs on one of my known-good chargers and give them a dummy-load workout... I'm not afraid of your batteries damaging my charger since I can fix it if they do anyways.
Actually... if you have a friend nearby who'd let you charge your batteries on their charger, the chance of harming a charger with a faulty battery is very small if you charge at 1A or so; I'd suggest you balance the packs, then try charging on another charger, and then double-check the voltage per cell with a power analyzer like the one I link above.
mnem
*adrift*
Uggh. That's NOT cool. I'm going to recommend a couple things;
First -
Get in the habit of balance charging and CHECKING the per-cell voltage after the charge completes EVERY TIME. And then after use, before you recharge, check them with a stand-alone balancer like the one below and balance the pack BEFORE RECHARGING if any cell is more than .05V away from the others. The balancing circuit in a modern LiPo charger can only make up for SO MUCH of an imbalance; they only have a certain amount of time before the pack reaches delta peak. Balancing a pack that's as far out as yours can take hours.
Second -
Make double damn sure your charger is doing its job; charge your new batteries, then discharge them using a dummy load, NOT the "discharge cycle" in the charger. For my 3S packs, I use a single 60W headlight bulb; for 6S, use 2 in series. You need to monitor them with a battery tester like this one:
http://www.hobbyking.com/hobbyking/s...dproduct=34137
which will sound an alarm if the connected battery becomes imbalanced, as well as a regular battery minder like this one:
http://www.hobbyking.com/hobbyking/s...rm_2s_6s_.html
to tell you when the battery is done discharging. If you get through the discharge cycle on a new pack and all cells are within .1 volt under load, your charger is PROBABLY working properly. If not, the balance circuit is probably compromised. This tester is the one I have; it will alarm if battery balance goes more than .04V off on any cell, which is good for an unloaded battery. It will probably go off on one or more cells with the battery under load when the battery nears 3.3V per cell; this is normal.
There is an array of transistors and resistors in the balance circuit; those transistors can develop a leaky junction or even short out as a result of voltage spikes caused by sparks when connecting/disconnecting a pack, or even from a brand new pack with very low internal resistance drawing too much current from the balancing circuit. The worst part is, this can happen and the charger APPEARS to work normally; voltages appear normal at the end of the charge, and the only way of knowing is that batteries start to fail repeatedly in the same way.
I had a brand-new 4S 25-50C rated Nano-Tech kill my iMars charger this way; the internal resistance on it measured like 5 milli-ohms! I found after the first charge with that battery that subsequent charges never charged accurately on 2 cells; it had actually drawn enough current through the balance circuit to kill 2 of the inputs on the voltage monitor D-A converter. After that, I never charge at more than 2 amps on that pack; though I have charged as high as 6A on my 3S packs.
Right now, I'm in the process of rebuilding one of these:
http://www.hobbypartz.com/75p-t6-multi-charger.html
that I picked up off eBay for $17; the one channel that appeared to work seemed to charge normally to an even 4.20V/cell; it even tested right with my Power Analyzer. I would never have known there was something wrong with it if it weren't for the fact I left a battery connected which I had observed charge up evenly to approx 4.19V per cell just before I sat down to watch TV with wifey for a few hours; when I went to disconnect it, I found one cell had dropped to 3.9V. A little testing revealed it had a shorted transistor (about the size of a grease ant) in the balance array on that channel.
My point is this; if you're not checking the cell balance of your batteries EVERY TIME you charge (I do), one of your batteries could have damaged that cell of the balance array on both your chargers and you'd never know.
Too bad you're so far away; I'd be glad to charge your packs on one of my known-good chargers and give them a dummy-load workout... I'm not afraid of your batteries damaging my charger since I can fix it if they do anyways.
Actually... if you have a friend nearby who'd let you charge your batteries on their charger, the chance of harming a charger with a faulty battery is very small if you charge at 1A or so; I'd suggest you balance the packs, then try charging on another charger, and then double-check the voltage per cell with a power analyzer like the one I link above.
mnem
*adrift*
I don't understand why you don't have a job!
Thanks as always!
b
01-13-2014, 05:13 PM
#1363
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I don't have any probs with the 3s packs on either charger but your right it could have damaged some of the parts that do 6s. I hope it hasn't damaged my chargers. I have a mate that I can give the 2 6s packs to and see what happens on his charger.
01-13-2014, 06:41 PM
#1364
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Yup... I've just charged and discharged them and the dodgy cell only charges to 4.02 and the others goto 4.20 or 4.19. Tried on my two chargers same thing.
I've just sussed out some turnigy 3000 6s packs for around 50 bucks each delivered. I think I'll just get two of those and call it a day.
I've just sussed out some turnigy 3000 6s packs for around 50 bucks each delivered. I think I'll just get two of those and call it a day.
These have been good to me!
b
http://www.hobbyking.com/hobbyking/s...dProduct=15012
01-13-2014, 06:46 PM
#1365
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I might just buy some more 2200 packs and make a series adapter and run 2x2200's in series to make 6s. Then I can use these packs in the axn and on the quad as well.
Last edited by ahamay; 01-13-2014 at 08:33 PM.
01-13-2014, 09:27 PM
#1366
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Yeah, I don't know either, aside from the whole pesky "expecting to get paid for what I know" thing, not the "How many can I move in an hour" thing.
Thanks for the detailed post. I always check the packs with my cell checker straight after charging and then again at the field before they go into anything. I discharged the 6s packs with 2 25w bulbs (man their bright) and the dodgy cell drains much faster than the others. Also when charging them now the dodgy cell charged up to 4.2 much faster than the others. After doing this a couple of times the dodgy cell will not charge up past about 4.05 even after hours.
I don't have any probs with the 3s packs on either charger but your right it could have damaged some of the parts that do 6s. I hope it hasn't damaged my chargers. I have a mate that I can give the 2 6s packs to and see what happens on his charger.
I don't have any probs with the 3s packs on either charger but your right it could have damaged some of the parts that do 6s. I hope it hasn't damaged my chargers. I have a mate that I can give the 2 6s packs to and see what happens on his charger.
Jonesey -
Mmmmhmmm...
Sounds like you're doing like you should, aside from not doing the check & balancing ritual after discharge as I outlined above. This IS important; you should make sure the batteries are at least balanced, if not charged to a storage charge, the same day they're flown. Repeatedly storing them discharged and/or in an imbalanced state can greatly increase the likelihood of the sort of failure you experienced.
Do you have a standalone balancer?
The short charge time behavior you describe is typical of a weak cell (like you didn't know that
); but now the question is whether the packs died because of an overabundance of suck and your chargers are both fine, or because something failed in the charger, or because they damaged your charger in similar fashion to the way mine was damaged.The only way to find that out is to test the charger as I outlined earlier with new or known good 6S batteries.
Do you have a mate who might loan you a known good battery you can test charge then run down as I outlined?
Good luck my friend,
mnem
Rule # 17: The amount of random suck that will be visited upon you in any venture is directly proportionate to the likelihood of said random suck making it look like you did something incredibly stupid. Multipliers can be counted upon for: Number of witnesses, prolonged exposure to the witnesses, and the number of witnesses who are important relatives, friends, or bosses. Yes, multipliers do stack.
Last edited by mnemennth; 01-13-2014 at 09:58 PM.
01-14-2014, 03:48 AM
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b
(ouch)
01-14-2014, 04:27 PM
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[Random Mode]
Hey!
I resemble that remark!
Ummm... what's a 20C? I have some Hi-C... will that do?
mnem
Nurse - I need 20CCs of flibbertygibbettonium... STAT!
[/ Random mode]
Hey!
I resemble that remark!
Ummm... what's a 20C? I have some Hi-C... will that do?
mnem
Nurse - I need 20CCs of flibbertygibbettonium... STAT!
[/ Random mode]
01-14-2014, 08:52 PM
#1370
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Don't get to bored with this lazy AXN flight to test the new BEC. I've passed my two suspect 6s packs onto a mate of mine to try on his charger. We'll see what he reports.
http://www.youtube.com/watch?v=X9bL0dSu3js
http://www.youtube.com/watch?v=X9bL0dSu3js
01-14-2014, 08:53 PM
#1371
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01-15-2014, 03:30 AM
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Great flyin' and great blather! Some observations: 1) Your flying skills are causing the field to get too small! 2) What's yer next bird? 3) How'd the ESC do? I got no "money shot" after 20 minutes of your piffle??? Grrrrr! Don't make me come over there ****!!!
01-15-2014, 02:27 PM
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Hmmm? I knew that these printers would be good for something....
http://lunevalley.weebly.com/custom-...tom-parts.html
http://lunevalley.weebly.com/custom-...tom-parts.html
01-17-2014, 05:02 PM
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