Velleman-Kit K2649, Иллюстрированное руководство по сборке

Страница: 17 / 28

17
The set temperature is displayed when you push the button S1.
You can change it by gradually turning potentiometer RV1 until the display shows the desired temperature.
With the standard values for R2 and R33 (91K resp. 22K), the adjusting range is about 5 to 30°C (40 to 85°F).
You can change this range by using other values for R2 and R33 :
You can also experiment yourself in order to obtain an optimum adjusting range for your application.
Solder a 1M trimmer parallel to both R2 and R33 (see fig. 7.0).
Adjust both trimmers so that you obtain the optimum range.
Afterwards replace the trimmers by normal resistors which approximate the set value as close as possible.
17. Use
Range R2 R3
-50°C (-60°F) to 0°C (32°F) 51K 7K5
+50°C (120°F) to 100°C (212°F) 33K 12K
+100°C (212°F) to 150°C (300°F) 33K 16K
Use