Re: thermister

Jim Thompson wrote:
On Wed, 09 Jan 2008 20:33:03 GMT, zekfrivo@xxxxxxxxxxxxxxxx (GregS)
wrote:

In article <ca9ao31b1a3dfrhfuckh4mrjcssbsntjhl@xxxxxxx>, legg <legg@xxxxxxxxxxxxxxx> wrote:
On Wed, 09 Jan 2008 19:27:18 GMT, zekfrivo@xxxxxxxxxxxxxxxx (GregS)
wrote:

I'm trying to reverse engineer this controller. I can't find anything yet on
its thermsiter. Its a 3 wire thermister, but the third wire
does no go to itself. It appears like two thermisters a 6 ohm and a 36 ohm
series
combination. Top, bottom, and juncion. I'm trying to find a similar
thermister. ??
Is it sealed in a vacuum?

How is it used in the circuit?
Its a black bead, pretty small. I don't yet know the circuit. It might be a
heated thermister.

One heater controller I made years ago, I simply used a thermister
driven with high current generating heat. If the liquid had dried up or vanished,
the heater would basically shut down automatically, because
the air could not dissipate the small amount of self generated heat.

greg

A bit scary... maybe... someone will lecture me on vapor pressure...

The typical automobile low-fuel indication is done using a self-heated
thermistor. When it no longer contacts fuel its self-heating causes
the resistance to plunge operating a relay ;-)


My old Chrysler had that for the oil level. All the cars I had since do not have an oil level indicator at all. Only oil pressure and when that lamp comes on it's often too late, meaning blue smoke coming out the tail pipe.

--
Regards, Joerg

http://www.analogconsultants.com/
.