Miniature Glass Component With Resistance Not A Diode In A Rechargeable NIMH Battery Pack

[Wild_Bill]

I can't recall what a glass-enclosed device is called which I think is a
capacitive component with resistance.
This component shows 11k ohm resistance and no difference in polarity, and
checks equally the same with a DMM diode test.

This just looks like a small axial lead glass diode (~3.8mm long) without a
cathode mark, copper colored dies at each end with a tiny gap between them.

The pack has three external terminals, of course (+) and (-) and a 3rd
sense/charge terminal.

The component's place inside the battery pack is between a third external
terminal and joined at a junction with the external negative terminal.
The battery negative battery contact is connected straight to the external
(-) terminal, and this device is between the negative terminal and the 3rd
external contact.
(not too swift at ascii art).

Thanks

--
Cheers,
WB
.............

[Paul Drahn]

It's a thermocouple to tell the charge controller how warm the battery
pack is getting while being charges. A sudden peak in temperature tells
the controller the pack is fully charged. At that point it may either
shut off or go to a trickle mode, depending on the charger design.

Paul

[Jon Elson]

Paul Drahn wrote:


> It's a thermocouple to tell the charge controller how warm the battery
> pack is getting while being charges. A sudden peak in temperature tells
> the controller the pack is fully charged. At that point it may either
> shut off or go to a trickle mode, depending on the charger design.

Not a thermocouple, but a thermistor. A thermocouple would have
a couple Ohms resistance, tops. 11K sounds very right for an
average thermistor. otherwise, what you say about temperature
measurement is right.

Jon

[Paul Drahn]

Yup. Right you are.

Paul

[Wild_Bill]

Thanks, Paul.. I wasn't thinking of temperature sensing but I believe you're
correct. The CT types shown in the Semitec pdf appear to be the same.
http://www.semitec-usa.com/product/index.html

I attempt to be thorough about details when asking questions, but left out
some this time.. the glass component was glued to the plastic jacket of one
of the cells.
Also, there are 2 Klixon temperature protectors inside the pack case.

I've often seen bimetal type temp protect devices used in rechargeable
packs, and fewer self-resetting polyfuse devices, also resistors a couple of
times and diodes a couple of times.

--
Cheers,
WB
.............


"Paul Drahn" <pdr...@webformixair.com> wrote in message
news:klonrv$5dm$1...@dont-email.me...