Thermistor module expects 10k pullup

[gfwilliams]

It seems to me at least - and this should be different depending on the thermistor. Maybe an option is needed.

Also 'Thermistors' should probably reference it better, and circuit diagram ought to really show current limiting resistor as optional.

[peter-clarke]

This actually occured to me a while ago. A the pull up is dependant on the type of bead although I know from memory the top two are 10k.

Yes agreed that the current limiting resistor should be indicated as optional.

[gfwilliams]

I'd imagine it doesn't actually matter that much what resistor you use as long as it's about right - my gut feeling would have been to use one that fits with the temperature range you expect to measure - but then there's self-heating/etc to worry about.

Also if someone really cared about accuracy they might want to measure their 10k resistor's value and put that in, as it's probably not spot on unless they've spent a lot of money.

[peter-clarke]

I used some high precision SMD resistors when I made the HVAC board which
worked okay but had previously tested with similar success using through
hole resistors.

Personally I tend to only use the first two on the list which happen to
require a 10K bias because its the most popular.

We do not measure the resistance of the cable to the sensor nor take into
account any heating etc. for commercial units so I would say you can ignore
that. Providing any cabling to the sensor is screened with the earth
connected at only one end you will have no issues over even significant
distances.

To be honest the bias resistance could be measured and used but its not for
commercial units so figured it would be sufficient to hardcode this. I
might add a functionality for a temperature offset although from experiance
its not linear so never really works.

I think someone was after a way of characterising their own sensors on the
Espruino forum. I have an excel spreadsheet which gives you the correct
figures to use in the Steinhart Hart equasion if you know the temperature
and the resistance over a number of readings. Would you like me to add
this in the module folder?