It finally happened to me :-( the BC-900 v32 toaster oven

[VidPro]

I was wondering what was going on :duh2: , they had been on the charger for a long time, and it wasnt saying "full" yet or reading the test Miliamp capacity or nothing, and the batteries were a bit hot.
oh well, i will just let it finish up, , to busy to mess with it now. . .

next day, hey i wonder how them batteries are doing . . . Hmm still at the same place , something must be wrong, let me just reach up here and :sick2:auuuu:sick2:gggghhh:sick2:, dang that was hot.

2 batteries on the inside 2 slots (the hotest ones) were Melted very slightly to the plastic around the Temp probe :shakehead of all things.
all 4 cells (perfectally new enloops) were so hot the wraper had peeled back , 2 of them are now completly ruined, the other 2 sorta work.

my Hypothisis is that the computer crashed :tinfoil: , yup, after having charged and topped-off and tested, now for , hundreds of rounds, it decided to crash like an MS operating system, and stop where the power was going to the battery, non stop. ( i am sorry dave, i am afriad i cant do that)

Without the stupid "smart" computer, there was no longer ANY thermal monitoring, there was NO cut-off, there was no slow down, there might not have even been PWM current control anymore.
that is my theory of why it happened. the display had locked up, you know usually it blips about changing by tiny ammounts.

Once i "rebooted" the charger , it of course worked just like it always has. poor batteries, computers shouldnt treat batteries (or people) like that :nana:

it is possible that it was due to a power surge, i knew i shoulda put the thing on a UPS. and isnt that when things Getcha the worst, when you knew you should have done something before.

 

[shadowjk]

Re: It finally happened to me :-( the b900 toaster oven

Hm, is this why the manual tells you to unplug it when you're not using it? Because the computer needs frequent reboots?

 

[VidPro]

Re: It finally happened to me :-( the b900 toaster oven

manuel? :shrug: was there a manuel?

i doubt its a matter of the memory leaking , and resources getting used up, although the next super battery computer will probably have that problem. you know the one with the 2 gig flash memory card :thinking:

it is probably more just a power glitch from the outside that can caused the microcontroller to stop . . . in the middle of what it was doing, leaving the "states" unchanged. mabey it needs a serial debugger

if this thing was Old School, it would have a capacitor doubling the size of the little thing, and protecting the microcontroller itself from such occurances. then the thing could be set to STOP when the cap voltage drooped, and it would be totally protected. course that would be in the $100 model instead of the cheap one.

 

[shadowjk]

Re: It finally happened to me :-( the b900 toaster oven

The battery adapter puts out 3V, you could put some diodes and a backup battery across the wires ;-)

 

[VidPro]

Re: It finally happened to me :-( the b900 toaster oven

i noticed somebody put a extra capicitor in it before, i was thinking just one on the main power line would cover a surge.

there are times when it was plugged in operating for DAYS, either topping for days, or just empty of battery and sitting there.
but
i have never USED it without having to turn it on and off constantally anyways, because i dont usually get the batteries in and adjust things fast enough, before it starts doing its own thing.
so my normal use of it does include unpowering it, after battery insertion.
but it has been pluged in for as long as 18day at a time, doing nothing but waiting, or topping.

edit: and of course this is the first time i have ever seen the display stop, so as far as i can tell this would be the first time it ever stopped when it was on, and plugged in.

 

[VidPro]

How To Tell your enloops are hosed

Ok i am going to put up the obligitory pictures.
and then i realised they had vented.

so mabey this is titled "How to tell if your Enloops are Ruined" :mecry:

some of the clues can be readily seen , if you look closely :thinking:, or even if you look from across the room, you notice that the wraper has peeled back a bit, it is assumed that this is due to extreeme heat conditions.

 

[VidPro]

Re: It finally happened to me :-( the b900 toaster oven

also around the nipple of the battery (we can say nipple cant we?) is a white substance, this is an indication that it vented enough to spew electrolyte out.
what is missing is the telltale brown streaks that come from the ventholes, but that probably happens over time. when the elecrolyte reacts with the moisture in the air.
this stuff is a crusty powder, the battery was probably sizzling for a long time

only about 1/2 of the electrolyte leaked out to the nipple end there, the rest of it is actually UNDER the white top cover of the battery.

this was really hard to see, because there is the white thing there, i noticed it first in my own pictures , (ok so maby i need glasses)

 

[VidPro]

Re: It finally happened to me :-( the b900 toaster oven

there is very little damage to the charger, as far as i can tell it still works
for me the funny thing is to see it melted by the thermal probe

i changed the lighting, so you could see the beump in the center of the charger.

 

[VidPro]

That ought fix it the b900 toaster oven

now i am gonna go all old school on the charger, i got nothing to lose

lets see your enloop charger do that huh

 

[Bones]

Re: It finally happened to me :-( the b900 toaster oven

...
there is very little damage to the charger, as far as i can tell it still works
for me the funny thing is to see it melted by the thermal probe
...

That would be the thermal probe that is supposed to protect against overheating, and bulging, and blistering, and melting, and venting and ... ?

Still, it's good to hear that 'only' the charger and cells suffered VidPro. Another reminder not to charge on surfaces that could exacerbate these situations.

This has me wondering though, if there's a device out there that will cut off the power supply as soon as it's interrupted?

Regardless of whether it causes an event like this, it seems to me that once the settings are lost, it's always better to have the plug pulled than it is to have the charger remain powered on, even if it manages to some sort of reset.

 

[shadowjk]

Re: It finally happened to me :-( the b900 toaster oven

I have plug-in RCD that also trips on powerloss.

 

[SilverFox]

Re: It finally happened to me :-( the b900 toaster oven

Hello VidPro,

Bummer... Those cells are "cooked."

Do you happen to remember what charge rate you were using?

Tom

 

[FlashCrazy]

Re: It finally happened to me :-( the b900 toaster oven

I like your "fix" with the big capacitors...lol. Does yours have the v32 or v33 software?

 

[VidPro]

Re: It finally happened to me :-( the b900 toaster oven

i think i was charging at 500, and it was in test or refresh mode?
some mode where it would have been working for a While anyways.
usually i know what mode i put it in when i started the process, and why i was using that mode, but by the time i get back to it , after dealing with 17 other projects and things, why i did it that way back then, i dont remember.

its version 32, the old one, i never thought that i would have to upgrade it, because it never missed a termination or anything ever, untill this day that it Locked-up.
and until i saw it for myself, i always thought it was due to missed termination, not a computer glitch.

 

[NA8]

Re: It finally happened to me :-( the b900 toaster oven

Sounds like your microcontroller went into dreamland and never woke up. You'd think they'd have a resetting countdown timer for protection against that sort of thing.

I did the capacitor mod that fixed the excessive resetting that mine did. After that I got the thermal shutdown mode when charging 4 AA's at 1 amp. My best luck was at 700ma charge current for AA's. One or two batteries seemed to give it less trouble than four.

Luckily a Maha MH-C808M charger should show up in a couple of days.

 

[Vikas Sontakke]

Re: It finally happened to me :-( the b900 toaster oven

Who makes this charger (which became toaster oven)? I always get confused between bc900 and b900.

- Vikas

 

[SilverFox]

Re: It finally happened to me :-( the b900 toaster oven

Hello Vikas,

It is the LaCrosse BC-900. Not to be confused with the Maha C9000.

Tom

 

[UncleFester]

Re: It finally happened to me :-( the b900 toaster oven

Vid Pro you're lucky. When mine did that it was auditioning for a remake of The China Syndrome.
I had been using it for more than a year to charge AAA nimhs. The 200ma default charge rate is a large enough percentage of the capacity for an AAA battery to generate a good negative delta V. It worked wonderfully so I got complacent. The melt down occurred when I put in 4 AA cells and left it at the default 200mA. That current isn't enough to generate a reliably detectable negative delta V when the cells are full so the charge doesn't terminate.
And so I joined the BC900 roast.

 

[Mr Happy]

Re: It finally happened to me :-( the b900 toaster oven

The melt down occurred when I put in 4 AA cells and left it at the default 200mA. That current isn't enough to generate a reliably detectable negative delta V when the cells are full so the charge doesn't terminate.
And so I joined the BC900 roast.

That's a bit odd. When I run a break-in charge on my C9000 it uses 200 mA on 2000 mAh cells (0.1C), and at the end of 16 hours the cells are not warm at all. It doesn't seem to me that 200 mA is enough to heat up an AA cell. At a supply voltage of 1.5 V the cell would only be dissipating 1/3 watt on overcharge. That shouldn't make it more than a few degrees warmer than room temperature.

 

[Vikas Sontakke]

Re: It finally happened to me :-( the b900 toaster oven

I thought LaCrosse had fixed all these issues with the latest firmware :-(

I guess I will stick with my classic Rayovac 1-hour charger (PS3 ??) for my needs.

- Vikas