Battery Problem

[Muncher]

A friend got a Polaroid 3.2 mega pixel PDc 3070 recently, came with 4x AAA alkaline batteries, worked fine with those.


I bought her some Uniross AAA 1.2v 700ma NiMH batteries to use in it and a charger. On the pack it says although they are 1.2v they are suitable for all 1.5v applications.

When the batteries are fully charged and put in the camera, it simply does not turn on! A replacement set was bought and the same thing happened.

I've tested the batteries with a battery tester and they are all showing well over 1.5v, maybe nearer 1.7v.

Anyone got any ideas?

[simpo two]

I'd be worried that a 1.2V battery is giving 1.7V...

But I'm sure it's the fact that NIMH don't give the same voltage as alkaline. Maybe that camera really needs a kick to get it going?

Not much use though if you're stuck with alkalines.... £££

[LongQ]

FWIW my Sony U30 came with 800maH rechargeable AAA's which seem to last longer than Duracell's. (But only needs 2)

However I also have used AA rechargeables quite a bit in the past and fouond that the failure rate is quite high from an early age. In fact the last set of 4 I bought had a duff unit included from new - showed as charged but didn't really have any charge to work with on load and gave similar symptoms to those you are experiencing iirc.

[joust]

[ techy mode]
You are measuring "unloaded" voltage. If you do the same with a 1.5V alkaline you'll find it's not actually 1.5 but more like 1.7 to 1.9.

Multimeters are very high impedance on their voltage range so as not to add much when you measure the voltage (1/Rtotal = 1/R1 + 1/R2, if R2 is high then Rtotal is very close to R1).

What you really need is an analogue multimeter that has a "load circuit" in it - usually shown as a battery test, which then loads up the cell and measures the voltage across that.

Some cameras are very fussy about their voltage circuit, and the fact that NiMH are 1.2V under load can confuse them.
[ techy mode off ]

However, reading the manual for the 3070 it says that you should only use Alkaline batteries, so I'd suspect that unless you've been incredibly unlucky you can't use NiMH with the camera. Your only last shot is to try NiCAD batteries as they sometimes will give a better "under load" voltage.

Guess you've just found out why Polaroid is going down the pan....

J

[Muncher]

joust said:

[ techy mode] You are measuring "unloaded" voltage. If you do the same with a 1.5V alkaline you'll find it's not actually 1.5 but more like 1.7 to 1.9. Multimeters are very high impedance on their voltage range so as not to add much when you measure the voltage (1/Rtotal = 1/R1 + 1/R2, if R2 is high then Rtotal is very close to R1). What you really need is an analogue multimeter that has a "load circuit" in it - usually shown as a battery test, which then loads up the cell and measures the voltage across that. Some cameras are very fussy about their voltage circuit, and the fact that NiMH are 1.2V under load can confuse them. [ techy mode off ] However, reading the manual for the 3070 it says that you should only use Alkaline batteries, so I'd suspect that unless you've been incredibly unlucky you can't use NiMH with the camera. Your only last shot is to try NiCAD batteries as they sometimes will give a better "under load" voltage. Guess you've just found out why Polaroid is going down the pan.... J

Cheers J,

I will see if she can take the camera back, it's a bit rubbish if it can only use Alkaline batteries!