[NTLK] How important is the Battery's temperature switch

Andrei Chichak newton at chichak.ca
Thu Nov 4 11:01:36 EDT 2010

The temperature sensor is used during the charging process. NiMH batteries are charged until they start to heat up, then they are full. The temperature probe tells the Newt the temperature so that it can haul down the charge current so the batteries don't boil and rupture. This is the little black matchhead looking thing. 

The yellow piece of paper looking thing is a resettable fuse, if the pack either draws too much current charging or is called upon to provide too much current while running (Newt screwup or accidental short), the fuse (polyswitch) will open up and stay open until the fault is removed.

Are they important? The lack of a temperature sensor will either tell the Newt that the pack is always cold (and the pack will be overcharged) or hot (and the pack will never be charged). The lack of the polyswitch is a little less critical, you don't need it until you do.


On 2010-November-04, at 2:53 AM, Tim Kaluza wrote:

> Hi there!
> I did do a Batterie replacement, made something wrong and put it now the right way in it. But I forgot to use the temperature switch. Well I wanted to forget it, because I'm not sure about it working the right way it should. 
> I got some quite good Sanyo rechargeable batteries in the unit. 
> What do you think? Should I reopen it and fix it? How much can 100mA do to my Newton? ^^. 
> Right now it is running in a old test unit quite well.
> All the best!
> Tim
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