Nizo Nightmare!

[akka10]

I have a dillema with my Nizo ... I hope someone can possibly shed some light on this for me. A while back, I pulled out my Nizo 4080 out of hibernation to shoot some stuff. I had not used it for about 18 months. After ongoing power problems, I had bought a Powerex "Smart Charger" in the hope of ressurecting/conditioning the old 1.2v 650 mah nicads in the camera's accubox.

http://thomas-distributing.com/maha-mh-c204f.htm

So I conditioned & charged them on the unit as per instructions, and then tried to run/turnover my 4080 with them. When I depressed the power button (not the roll button) on the back of the handgrip to power up the camera, it started making a motor whirring sound, even though the camera was not actually turning over! And that is all it would do. Make a running sound, even though it was not turning over. No other functionality seemed to be present. I checked and double checked I had put the batteries into the accubox correctly and all was okay. But it still would not function correctly when powered up. So I figured she was broken, and I contacted Kurt Schacherl in Germany, and sent it to him. I have now just heard the bad news back from him. The lightmeter is dead (presumably fried), along with some electronic components, and a switch in the handgrip. So he is going to fix it for me, luckily he has parts! But this all leads me to wonder if my batteries and the charger had something to do with my camera's demise! I have heard of these lightmeter problems occurring with Nizo's, when 1.5v cells have been used. Though these were 1.2v cells, and I have always made sure I use 1.2v only! My worries then led me to think about the Polarity Reversal characteristic that can occur with nicads that have not been used for a long time, and have undergone 'deep discharge', thus ultimately reversing the cells polarity. I am now wondering if my 'smartcharger' detected this reverse polarity in the old cells, then charged them with a reverse polarity! Then I basically drove a strong surge of reverse polarity through my Nizo, thus 'frying' several electronic components within. Could a nicad hold a reverse polarity charge, if it had gone through polarity reversal, and been charged in reverse? Would a smartcharger charge this way? Or is this all just due to the camera's age and bad luck? I just feel the fact that I have had it for about 16 years, with few problems, then now this problem coincides with me trying out a new charger system ...
I am glad I have found Kurt. He has been patient with my inablity to speak German. He seems to have the knowledge and PARTS! I will repost with the outcome of the repair job.
If anyone can shed any light, I would really appreciate it. As I really want to avoid future problems, especially after paying to get her fixed!!

Alex Orr :oops:

[christoph]

i'm not an expert but it seems unlikely (or lets say impossible) that you could charge an rechargable with reverse polarity.. it just contradicts everything i know about how batteries work.

i have three sound nizos myself and occasionally used 1.5V batteries, never had a problem (i stopped using them though since i dont want to force my luck). personally i think you just had bad luck, the nizos seem to have some tender electronics, sometimes one blows.

if you're having problems communicating with kurt schacherl, give me a yell.
++ christoph ++

[akka10]

Thanks Christoph. I am hoping this is the case. I try to take a lot of care with my cameras, and I hope I am not responsible for damage! Thanks very much for your offer to be 'translator'. Very kind. I might take you up on it! I will be talking to Kurt again soon, if we have problems understanding each other, I will be in touch!!!

[discs of tron]

i have a 4080, with the box for the 6 1.2 vbatteries. i have a length of bolt, approx 1/4" in diameter, cut to the length of a aa battery. wrapped gaff tape around it until it's the width of a battery. when i use aa's (1.5 v,) i use 5, with the bolt thing as a "dummy." that drops the voltage down into non-frying territory. i haven't had any trouble with this setup so far.

(this is of course not a direct response to your situation, but an idea for anyone who doesn't have/ needs an alternative to nicads.)

[S8 Booster]

I have a dillema with my Nizo ...

My worries then led me to think about the Polarity Reversal characteristic that can occur with nicads that have not been used for a long time, and have undergone 'deep discharge', thus ultimately reversing the cells polarity. I am now wondering if my 'smartcharger' detected this reverse polarity in the old cells, then charged them with a reverse polarity! Alex Orr :oops:

just giving some brief inputs as i am short of time going to nihon desu in a short while and time runs out due to ample preparations...

anyway, a smart charger should not reverse charge ur batts. it should only discharge and re-charge - read "re-condition" your battery - one or more times. whether or not it does this individually or for all - if more charged at the same time i have no idea of.

if a NiCd batt does not take charge it it possible to give it a short reverse charge and then correct charge again to get it alive but to my experience it will be nothing like new again.

same procedure can somewhat fix the memory effect. anyhow without proper knowledge on how to do thid may cause batts to explode so do not experiment with it!

if NiCds are charged in series and the batt conditions are individually uneven i belive to remember that some "damaged" batts can individually adobt a reverse polarity. pretty sure i know that from big power backup systems getting unwary useless if not maintenanced regulary.

nevertheless: if one or 2 batts should get a reverse charge it will not damage ur cam but it will not work and in theory you may get the result u describe

also, if all batts were reversed or all batts put into the cam incoorectly there should be a diode in the main circuit or at a critical point in the powersupply chain that should prevent damage by blockin reverse power flow but i can not guarantee this for ur cam.


Short note on Nizo/1.2v cells cams n Canon 8/1014 xlss since it was mentioned earlier.

generally use 1.2v on cams designed for it but NiMh is far better than NiCds due to no noticeable memory effect. seems like nizos designed for 1.2vs are better off with 1.2vs as some electronic components may get more fragile by ageing. capacitors for 1.


using 1.2v cells on the canons are not particulary smart by any measure. it uses at least 2 real stabilized power supplies for various oparations/controls in the cam amongst other the ultra fast exposure/iris control.

a 1.5v to 1.2v/cell drop will then only increase the current draw from the battery which again drains the batts much faster than expected despite the enhanced capacity. the system voltage will will aways be near(er) its low minimum and if the cart is a bit sticky or say shooting extra thick neg film the cam may stall due to its electronic protection system due to either too low voltage or to high current draw.

experiened this with my 1014x when trying 1600 mA NiMhs with a bad cart of the past. well charged batts. installing high power panasonic powermax3 for high current draw portable digital audio system fixed that.

panasonic reomends a certain 1.5 v batt for s8 cams called the super. as far as i know this is a long duration constant performance batt with moderate but far sufficient power drain for s8 cams.,

the 1014xs is extremely fine of with the powermax3 though as i suspect it being a little dry in lube land these days offering more resitance than it should in the drive train.

i think i have to open that maze box and lube it soon.

s