GCinDC's Giant DH Comp

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dnmun   100 GW

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Re: GCinDC's Giant DH Comp

Post by dnmun » Mar 24 2013 12:36pm

why do you have to be so stupid and insulting? you could just be quiet and you would not be so offensive. seems like you always gotta make some insulting statement or prove how truly ignorant you are.

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Re: GCinDC's Giant DH Comp

Post by chroot » Mar 24 2013 12:47pm

Hey guys, Lets be adult and no need insult each other.

You all need remember we are not perfection human being so Greg made his mistake gotten
him trouble. No one is invincible! Just like what happened to my Headway battery pack got fire caused
by shorted. Lets move on please!
Thank you Justin Lemire-Elmore - You are a HERO!

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Re: GCinDC's Giant DH Comp

Post by Ykick » Mar 24 2013 1:17pm

chroot wrote:Hey guys, Lets be adult and no need insult each other.

You all need remember we are not perfection human being so Greg made his mistake gotten
him trouble. No one is invincible! Just like what happened to my Headway battery pack got fire caused
by shorted. Lets move on please!
Good post, we're storing energy which carries the risk of fire. Always has, always will.

Re-reading my previous post 'didn't intend to armchair QB but merely observations of what may or may not have led up to this event and the flammable liquid storag? I applaud Greg for sharing this (amid some silly PG flak) and glad it's mostly cleanup and no injuries.

'sure whatever you come up with will be better than ever!
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Re: GCinDC's Giant DH Comp

Post by etriker » Mar 24 2013 2:19pm

It freaks me out !

Lipo rules are for newbees only ?

Why are we seeing long time members being so careless with rc lipo ?

He is so blessed his whole house did not burn down ! ! !

This was almost the big one we have been praying would not happen.

Does someones family have to die before we get it ? ? ?

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Re: GCinDC's Giant DH Comp

Post by GCinDC » Mar 24 2013 3:09pm

good. be freaked out. just don't be an ass. assholes are as assholes do.

i'm not saying you are. i don't know you. just think twice before you judge someone. call me crazy? be specific. you may think i ride like a madman, but any serious biker knows that i take calculated risks. there are a lot of things that look crazy to me, but the riders are in control. i think it's crazy to go flying over jumps w/o being able to see the landing! that's why i prefer flats to flat. all is relative. don't judge what you don't know. it is far more honest to say it freaks you out. thank you.
etriker wrote:Lipo rules are for newbees only ?
the rules of physics apply to everyone. i'm not sure what's confusing here. the lipo rules have always been: never below 2.7V, never above 4.3V, and never puncture. those are the rules. i apparently broke the rules. let's take a poll of lipo users and see who've had cells above 4.3V and below 3V. the rest, like in that article, is a lot of good advice. you may even consider them rules too. maybe i will stop charging unattended. i think a smoke detector may be more reliable than me and an eaiser solution. either way, i wouldn't consider that a rule. that dude is no scientist. he even says:
John Salt on his About Me page wrote:So why do I claim to be an RC helicopter expert? Hey, I never claimed that. There are radio controlled helicopter pilots who could fly circles around me. There are aeronautical helicopter engineers who can teach you way more theory than I ever could.

I am simply an ordinary person and average flier who loves the RC helicopter hobby and wants to help others experience that same passion while avoiding many of the common mistakes and pitfalls.
i'm no expert either. i learn everyday. i make tons of mistakes. i document them too for your benefit. in lots of ways i'm still a noob. but there is no us and them. we're all individuals with different levels of experience. don't trust anyone cause he was a member since 2008... read and read and read. and be freaked out.
Youtube channel, 2013 Highlights vid. Ebike Nerdcast.
Giant DH Comp: 20s lipo (11.6Ah), hs3540, Adaptto Mini-E, 900W BMSBattery charger.
GT I-Drive (sold), 20s lipo, 9C, 72V 45A 12FET.

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Re: GCinDC's Giant DH Comp

Post by GCinDC » Mar 24 2013 3:25pm

now, what to do with the garage?? before the fire, you may have noticed it was an unsightly mess. clearly i must change my ways on a variety of fronts.

having a clean workspace would be a good start. if you've got any pics of nice garage workspaces, please send the links for inspiration.

remember those home reno projects i was moaning about. well, i just fixed up the office playroom.

before:
Image
after:
Image
it's all ikea stuff. i don't have quite that budget for the garage tho!
Youtube channel, 2013 Highlights vid. Ebike Nerdcast.
Giant DH Comp: 20s lipo (11.6Ah), hs3540, Adaptto Mini-E, 900W BMSBattery charger.
GT I-Drive (sold), 20s lipo, 9C, 72V 45A 12FET.

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Re: GCinDC's Giant DH Comp

Post by etriker » Mar 24 2013 4:12pm

So maybe you will stop charging unattended ?

Are you kidding ? ? ? You think this is funny ? ? ?

I just bought some of these and there was a paper in the box with a warning saying do not charge unattended.

http://www.batteryspace.com/LiFePO4-Pri ... t-PCM.aspx

That really should be lipo rule #1.

http://www.horizonhobby.com/pdf/EFL-LiP ... rnings.pdf

http://www.allerc.com/battery.php

http://thunderpowerrc.com/PDF/TP-425.pdf

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Re: GCinDC's Giant DH Comp

Post by hydro-one » Mar 24 2013 5:08pm

better get another bag of birdseed for those mice WHO PISSED OUT THE FIRE!!!!! I think you will be asked alot of very detailed questions about the pack and where it came from . I personally do cell level monitoring during each bulk charge, the way you were charging , those db-25s cant handle eight amps especially is pins were loose etc. , there would have been a huge voltage drop during charge and mabye one cell group slowly became out of balance. the low cell group got hammered at LVC (which was too low IMO ) and was damaged. Then the most damaged cell in the group lost signifigant capacity, and when u plugged into charge all the charge kept hamming that cell too. . . then during bulk (!) charging of the cell group, that cell hit 4.2 long before the rest, and was probably being hammred at eight amps or more when it did. and then it kept going until it blew. this is very sililar to my buddys fire. ,. you must know every cell at HVC and LVC, , , and shit happens, lipos and wiring get damaged.

Im looking towards a light fiberglass fireproof shell that has a duct for fire with some sort of fire absorbing filter or baffle, like a mufler , , , with a filter to condense most of the real bad stuff. that comes out.........

I think the message is pretty clear what you should do.......feed those mice!! glad to still have you here, , mabye take a break from cycling for a while and rethink priorities..... :wink:
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Re: GCinDC's Giant DH Comp

Post by dnmun » Mar 24 2013 5:43pm

the CO2 level may have been so high that the fire could not sustain combustion enuff to keep the wood ignited.

you can do a new layout space in the garage and leave a space for a charging closet or box that would be lined with fire resistant sheet rock.

maybe have a wheel rack to hold the bike upright and then lower a sheet rock cabinet down over the bike while charging.

use some foam strips on the bottom edges of the box so when it sits on the floor the box is air tight except for the charging leads going into the box which could be sealed with fire stop where they go through the side or top of the box. this is a high temperature caulk used for sealing holes between floors to prevent spread of fire.

maybe have an access panel of sheet metal which would open and close on one side where you had to reach inside the box to make the charging connections. then close it when charging to keep the box sealed.

i already recommended people consider using the GFCI breakers for these alloy shell chargers because of the risk of a shock hazard. your charger became a shock hazard when the ground wire burned open. i have since opened a brand new kingpan charger and found that the ground was never even attached to the case during assembly of the charger. just loose inside the charger where it coulda shorted to the high voltage even. the switching mosfets can and do short to the case when they fail and if someone is grounded and picks up one of the chargers which is still active but has the high voltage shorted to the case and the ground is burned off then they could receive a serious shock.

smoke alarm. code now requires that all new smoke alarms be tied together so that if any one is set off then all of them in the house will alarm. this would require running another small wire from the garage back into the house to tie into the other smoke alarms. easy enuff to do. this may get you over the hump with the fire insurance if they get on your case about the source of the fire. maybe keep your rates from being jacked up too.

fire suppression. water sprayed on the heat source will reduce the temperature a lot and may prevent secondary ignition. in conjunction with a charging closet, using a spray nozzle and stored volume of water to be sprayed on the fire as soon as the thermal relay closes may be easy enuff, but you wanna have the water pump on a separate circuit from the charger because you can expect the charger to blow the circuit breaker.

you can rewire that service box with 240V from the service panel in the house using the current 12AWG romex running out there now. you could do it yourself or hire the guy who worked for you before. he will know how to wire the third wires for the smoke alarms too. he could install the GFCI breakers in that service panel in the garage and bring out several circuits from the panel there.

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Re: GCinDC's Giant DH Comp

Post by etriker » Mar 24 2013 6:05pm

dnmun wrote:the CO2 level may have been so high that the fire could not sustain combustion enuff to keep the wood ignited.

you can do a new layout space in the garage and leave a space for a charging closet or box that would be lined with fire resistant sheet rock.

maybe have a wheel rack to hold the bike upright and then lower a sheet rock cabinet down over the bike while charging.

use some foam strips on the bottom edges of the box so when it sits on the floor the box is air tight except for the charging leads going into the box which could be sealed with fire stop where they go through the side or top of the box. this is a high temperature caulk used for sealing holes between floors to prevent spread of fire.

maybe have an access panel of sheet metal which would open and close on one side where you had to reach inside the box to make the charging connections. then close it when charging to keep the box sealed.

i already recommended people consider using the GFCI breakers for these alloy shell chargers because of the risk of a shock hazard. your charger became a shock hazard when the ground wire burned open. i have since opened a brand new kingpan charger and found that the ground was never even attached to the case during assembly of the charger. just loose inside the charger where it coulda shorted to the high voltage even. the switching mosfets can and do short to the case when they fail and if someone is grounded and picks up one of the chargers which is still active but has the high voltage shorted to the case and the ground is burned off then they could receive a serious shock.

smoke alarm. code now requires that all new smoke alarms be tied together so that if any one is set off then all of them in the house will alarm. this would require running another small wire from the garage back into the house to tie into the other smoke alarms. easy enuff to do. this may get you over the hump with the fire insurance if they get on your case about the source of the fire. maybe keep your rates from being jacked up too.

fire suppression. water sprayed on the heat source will reduce the temperature a lot and may prevent secondary ignition. in conjunction with a charging closet, using a spray nozzle and stored volume of water to be sprayed on the fire as soon as the thermal relay closes may be easy enuff, but you wanna have the water pump on a separate circuit from the charger because you can expect the charger to blow the circuit breaker.

you can rewire that service box with 240V from the service panel in the house using the current 12AWG romex running out there now. you could do it yourself or hire the guy who worked for you before. he will know how to wire the third wires for the smoke alarms too. he could install the GFCI breakers in that service panel in the garage and bring out several circuits from the panel there.
Or you could just do like the instructions for all rc chargers say and don't charge batteries unattended ?

How are you going to keep an eye on the batteries when charging with a sheet rock cabinet down over the bike ?

Little windows ? Right ?

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knoxie   10 MW

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Re: GCinDC's Giant DH Comp

Post by knoxie » Mar 24 2013 6:14pm

hydro-one wrote:those db-25s cant handle eight amps especially is pins were loose etc.
It depends on the brand used, I use many different ones for differing projects some are rated at 17A at 100V DC the spec totally changes as some have nickel silver pins, some gold, sure some are only rated for a couple of amps some are much higher. In practice they can take many more amps and dont forget the BC balance charger pulse charges at 8A to help reduce heating when charging 1 x pack on its own through the very thin balance leads.

Greg has been unlucky, there is a risk for all of us who bring high volumes of lipo under our roof, sure there are things he should of done better maybe but he knows this now, I have always been very careful with my Lipo but then I have seen other people with horror show setups that dont have issues either.

Lipo is perfectly OK for us to use you just have to play by the rules and take pretty basic precautions thats all, its perfect for commuter use? I dont get that statement at all, its light, its powerful and cheap and safe as long as you handle it properly.

I am getting more subscribers joining my youtube channel and with Gregs fire in mind decided to do a quick safety video as I am always encouraging people to use this stuff and modify things its only fair newbies get to know how dangerous it can be too.

Hope Greg gets this sorted out and is back with a new routine and new batteries and bike really soon, you can write my name on a few of those packs for luck Greg :wink:

Electric KMX 72V Lipo, USPD drive unit. BMX 72V, Puma BMC,
Raleigh 26 inch MTB Puma 50V Turnigy 25C Lipo 10AH, Trek MTB, X5 48V NIMH. Electric BMX
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Re: GCinDC's Giant DH Comp

Post by hydro-one » Mar 24 2013 6:18pm

i like the idea of a |fume hood" for charging. --- I like the idea of a duct with a filter in it that condenses all the smoke. I think i will patent it it if hasnt been already done " lipo smoke condenserr for medium sized lithium packs" contained therin is a matrix of adsorbent medium, high flow, low particle pass. it is connected by a sealed duct to the sealed battery container. in case of exothermic reaction the case and duct will contain the toxic fumes and minimise smoke damage from particulate."

for indoor use i think all insurnace companies should make my device manditory. lol

either it burns or it dosent, may as well plan for the worse. seems to be the trend. :mrgreen: my other buddy whos lipo burned name was greg too lol
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Re: GCinDC's Giant DH Comp

Post by etriker » Mar 24 2013 6:22pm

That is why I said crazy.

How does he know his insurance man won't read this ?

He is already planning a new workshop and still might charge unattended ?

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Re: GCinDC's Giant DH Comp

Post by GCinDC » Mar 24 2013 6:35pm

etriker wrote:That is why I said crazy.

How does he know his insurance man won't read this ?

He is already planning a new workshop and still might charge unattended ?
open your eyes, and read what i frocking wrote, you asshole
GCinDC wrote:maybe i will stop charging unattended.
thanks for getting me thoroughly pissed off, on top of all the other shit i have to deal with.

christ, you sound like i burned down your garage.

now do me a frocking favor and frock the hell off. go deal with your own life. go for a frocking walk.
hydro-one wrote:i like the idea of a |fume hood" for charging.
that is an amazing idea! i love it!

see, etriker, that's constructive... unlike hysterical ranting...
Image
Youtube channel, 2013 Highlights vid. Ebike Nerdcast.
Giant DH Comp: 20s lipo (11.6Ah), hs3540, Adaptto Mini-E, 900W BMSBattery charger.
GT I-Drive (sold), 20s lipo, 9C, 72V 45A 12FET.

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Re: GCinDC's Giant DH Comp

Post by etriker » Mar 24 2013 6:40pm

You started out with god it's beautiful... look how everything melted. i've gotta take a ton of pictures. the guys are going to love this! too bad there's no video...

And now you are pissed ? ? ?

Why ?

Because you did not read the instructions for your charger and charged your batteries unattended and almost burned down the house ?

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Re: GCinDC's Giant DH Comp

Post by GCinDC » Mar 24 2013 6:45pm

what do you want? what can i tell you right now to make you happy?

obviously it's not enough that i said i'm going to pedal a bike for a while and think about it.

so what it the hell can i tell you?

you seem bent on proving i'm crazy. you want all the world to know and agree that i'm crazy. is that it? will that make you feel better?
Youtube channel, 2013 Highlights vid. Ebike Nerdcast.
Giant DH Comp: 20s lipo (11.6Ah), hs3540, Adaptto Mini-E, 900W BMSBattery charger.
GT I-Drive (sold), 20s lipo, 9C, 72V 45A 12FET.

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Re: GCinDC's Giant DH Comp

Post by knoxie » Mar 24 2013 6:55pm

Yes I have seen a lot of lipo packs let go, most that I have seen have only smouldered though they can flame of course but often when stifled inside a case especially the old point 1 packs I used to use that had aluminium cases and were full of beeswax and polystyrene! yes I know :lol: they just smouldered, never saw any flames.

You can charge unattended as long as its safe, you need to say well if this pack lets go the worst would be the clean up from the smoke damage and a new battery pack? you are pretty much always going to have to buy a new pack because even if you are in attendance right next to it the damage will be done before you have even got your hands on your fire extinguisher, the fire extinguisher being really to stop the surrounding area going up in flames as the exothermic tendency of the battery is very hard to control once established.

Its funny how polarised (excuse the pun) people are about Lipo, and Lifepo or Nimh or what ever, you will get fanbois and haters all along the line, I have used every single battery chemistry known in over 10 years of this hobby and would not even consider doing it any more if I had to use anything other than Lipo, A123 at a push if the price was right :lol:

Try not to let it get your back up Greg, I think sometimes things sound a lot worse on the page than they are in reality 8) nobody wants to see you have any issues ever again, to be honest and you know this already, my main worry for you was on the road not in your house :? I had a bad dream once about it, I am rather a big fan of your videos and often watched them late in to the night with a bottle of wine and a half :lol:

Again Greg if I can help in any way or you just want to vent (again excuse that one) you can Skype me up, I will stay up late for ya 8) I am off to bed now, take care.

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Re: GCinDC's Giant DH Comp

Post by AussieJester » Mar 24 2013 6:59pm

Christ if etriker saw my setup he would have kittens, i have 20ah of lipo sitting randomily on the
carpet behind me, another 15ah sitting on a chipboard bench, i have no cell level monitoring
whatsoever and whats this pissy 4.30v per self pfft noobs, 5v babee they can take it :twisted:
....smoke? anyone smell smoke? ah shit my garage is on fire what did i do wrong
:cry: :cry: waa waaa waaa... :roll: :mrgreen:

On a serious note, Great to see your ok Greg, could of been worse :shock:
it could of been your new bike Thuds building up with the mid drive rc setup! ;-)

KiM

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Re: GCinDC's Giant DH Comp

Post by bigmoose » Mar 24 2013 7:02pm

etriker, I am going to publicly ask you to tone it down... take a walk or have a drink... go smell a rose somewhere other than this thread.

IMHO something pretty tramatic happened to GCinDC and he is processing it. He was a good enough chap to share it, pretty much unedited, realtime, and raw with all of us so we could learn something. I am absolutely sure he has pondered it, processed it, and will make some future changes.

The man could have lost everything, and I for one, think as an other poster said, "someone upstairs was keeping an eye on things for him!" I couldn't agree more.

That said, I have done some things that seemed right at the time, and considering the outcome, were pretty foolish in hindsight. People mess up, organizations mess up... just ask NASA about launching Challenger!

I for one appreciate GCinDC's posts and the chatter and analysis that has ensued.

In my opinion you have moved into making ad hominum attacks on his character, and I believe they are out of bounds and not in the spirit of the board. I am asking you, respectfully and kindly to simply shut it down on this thread and move on.

All the best,
bigMoose
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Re: GCinDC's Giant DH Comp

Post by etriker » Mar 24 2013 7:03pm

I have thought about this a lot while riding and pedaling.

There would be way less ebike battery fires if people kept an eye on their batteries while charging like the rc charger instructions say.

I want you to not charge your batteries unattended.

I can't believe you said you might.

Pedal until you understand.

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Re: GCinDC's Giant DH Comp

Post by etriker » Mar 24 2013 7:04pm

bigmoose wrote:etriker, I am going to publicly ask you to tone it down... take a walk or have a drink... go smell a rose somewhere other than this thread.

IMHO something pretty tramatic happened to GCinDC and he is processing it. He was a good enough chap to share it, pretty much unedited, realtime, and raw with all of us so we could learn something. I am absolutely sure he has pondered it, processed it, and will make some future changes.

The man could have lost everything, and I for one, think as an other poster said, "someone upstairs was keeping an eye on things for him!" I couldn't agree more.

That said, I have done some things that seemed right at the time, and considering the outcome, were pretty foolish in hindsight. People mess up, organizations mess up... just ask NASA about launching Challenger!

I for one appreciate GCinDC's posts and the chatter and analysis that has ensued.

In my opinion you have moved into making ad hominum attacks on his character, and I believe they are out of bounds and not in the spirit of the board. I am asking you, respectfully and kindly to simply shut it down on this thread and move on.

All the best,
bigMoose
Big moose, I will never post on this forum again.

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Re: GCinDC's Giant DH Comp

Post by bigmoose » Mar 24 2013 7:05pm

I requested that you not post on this thread. If you want to leave the forum, so be it. Realize I asked for you to respectfully leave the thread only.
"Live simply. Love generously. Care deeply. Speak kindly. Leave the rest to God..." all the best, Dave

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Re: GCinDC's Giant DH Comp

Post by Axel » Mar 24 2013 7:54pm

Ouf ! (in french)
the forum will become constructive and friendly.
Thanks to leave the forum Etriker.
The world thanks initiatives, and if we had all read "the instructions", I think that the lipo's batteries would not exist, as this forum, and I would not met Greg one day in DC's street when I was driving my car at 35 miles/hours uphill in the traffic, I would not met my wife in the top of the Mont Blanc, I would not type in my computer now, I would not .....
So, thanks Greg to take me in this adventure, and we will continue all together !
Best,
Axel
:D :lol: :D

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Re: GCinDC's Giant DH Comp

Post by Trackman417 » Mar 24 2013 8:45pm

Damn it Greg! There was a really sweet deal on the for sale used thread to turnigy 6s lipos. I would have snagged em for you, but I found the deal after someone else did. That and this same guy was selling an icharger 208B. You said you needed a real balance charger? Right?

After some of the comments I have been reading, if Greg did not learn his lesson, then we can get mad at him. However, he has definitely showed signs of improving for a better tomorrow. I guess we can all agree that we have made mistakes and that: Foresight really sucks, but hindsight is 20/20.
I agree with Bigmoose, he has been awfully good at taking pics of just about everything, heck taking that video to show the damage was good as well. All of which was to help us not to make the same mistake he did.

You got some titanium balls Greg, showing us the stuff you did. I can't wait to kick your ass in a drag race when I stop by this summer. :mrgreen: :lol:
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Re: GCinDC's Giant DH Comp

Post by sn0wchyld » Mar 24 2013 8:56pm

well said bigmoose. etriker, chill out, take a walk, and understand that when greg's saying 'maybe ill stop charging unattended' hes actually saying 'I will', its just a turn of phrase to use 'maybe'. Regardless, 'charging attended' is unlikely to help much, if at all. At least in terms of stopping a catastrophic failure like this, at best you might be able to get the smoking/flaming mess out to a safe spot, but you 'aint gonna stop it altogether.

back OT, greg, great to hear you're ok, even if the bike's a bit frocked. sorry... frocked. My thought on reading the post mortum is this... you know atleast 1 or 2 cells were all but dead, but with the last few charges, you were paralleling the packs without first checking the individual cell voltages right (correct me if im wrong here)? so those cells may have been sitting at say, 3v, or 2.5v, or something lower, being paralleled with cells sitting at say, 3.6v, and then you're pumping in 8A ontop of that... so the already weak (or more realistically already dead) cells are having current dumped into them from the healthy cells they're paralleled with + most of the 8A from the charger... probably pushing them well over 1C or 2c charging, for an already weak cell... I mean, as far as I understand the 3.3v you were seeing on that cell group was after they were paralleled right? so that's the 'average' voltage for that group, with some of them under load 'charging' up the runt cell, which could have had resting voltage at or below 3v... That's my take on the cause anyway. the charger may also be too 'dumb', since it'd keep pumping power into the cells till the cows come home if it doesn't reach full charge, not cut out after a set amount of time, charged or not charged.

I had been planning on using a parallel to series 'block' like tench's http://endless-sphere.com/forums/viewto ... =2&t=39489 but now I think ill make some sort of protection/checking circuit to make sure there are no runt cells before paralleling the group. though im guessing runt cells like that would show their ugly head in the IR of the cell and other signs anyway, which my charger would probably pick up on...

anyway like i said mate, good to hear the damage wasn't too bad (given what could have happened!!), and that you and your fam are all a-ok. Shame 'bout the bike, that frame's probably a write off, but hey... just gives you the opportunity to build something better right? *cough* 40xx *cough* cromotor *cough* Johns 6phase *cough*.... :wink:

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