Main purpose:
Generated by temperature sensor signal, transferred to dozens of meters from the total control center of the industrial control, considering the signal must be without interference, because this often USES the current transmission mode, the temperature changes into the change of the current,
Design requirements:
1, design circuit corresponding to 20 degrees to 60 degrees temperature change into 4 ma ~ 20 ma current changes,
2, please set the lower limit alarm at the lowest point and in a setting high limit alarm point, and red leds alarm indication,