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kimmi
- 16th April 2006, 16:25
Hi all ...

PT1000 is a temperatur sensor R=1000 Ohm

How can I connect the PT1000 to my 16F876 to read temperatur

mabye as a RC 100nF / PT1000

or ?

Kim

sayzer
- 17th April 2006, 06:20
You should use ADCIN to read PT series.


Pls check http://www.picbasic.co.uk/forum/showthread.php?t=3720 for useful info.



------------------------------

kimmi
- 17th April 2006, 11:44
Tnx SayZer ...

no need for opamp for the adc

have tryed this :

(+)
|
10K
|
+------[47K]---+--> AD
| |
PT1000 100n
| |
| |
(GND) (GND)

and this to :

(GND)-- 100nF -- PT1000 -- > AD
this workes fair but not stabil (RC)

is ther a better way to do this ?

/kim

sayzer
- 18th April 2006, 06:00
For ADC input, no need for capacitor. RC or POT commands are painful to work with PT series.

Attached schematic is what I do to read PT3000.

For PT1000, 5K6 to Vdd needs to be determined experimentally.

Currently with this schematic, reading PT3000 is quite satisfactory.




'Added the schematic.

kimmi
- 18th April 2006, 06:39
Well I am new in this forum but canīt finde the Attached schematic do you use another forum for Attached files ?

/Kim

kimmi
- 18th April 2006, 12:01
tnx ...
now I can see it
will try it tonight after work ..

Kim

kimmi
- 20th April 2006, 07:20
Hi SayZer ..

Have tested it
but do we need to limit the current to 5 Volt 1 mA

/kim