Thermocouple cold junction compensator AD596 597 a circuit diagram of Temperature Monitor

  
Circuit from the AD596/597 form a temperature measurement and control instrument is shown in Fig. Here, AD596/597 (IC1) as a closed-loop thermocouple signal conditioner use. IC
Thermocouple cold junction compensator AD596 597 a circuit diagram of Temperature Monitor - schematic

2 is a monolithic CMOS 3 1/2 bit A/D converter ICL7136, can also be used to replace ICL7106, but power consumption will increase more. IC3 is + 5V bandgap reference voltage source AD584, + 5V reference voltage after R4, R5 partial pressure ICL7136 to provide a reference voltage of 1.000V, composed by the ICL7136 and LCD display for 2V full scale digital panel meter (DPM). IC4 selects OP07 operational amplifier. RP is the set point adjustment potentiometer for setting the temperature to be controlled T1. Optocoupler IC5 with triac (TRIAC) is.The instrument has a temperature, temperature control, and open thermocouple failure alarm. AD596/597 output voltage by R1, R2 divider to the ICL7136 after the analog input IN +, IN-. Take R1 45.2k, R2 10k, the instrument display Fahrenheit (oF). Appropriately adjusted R1, the resistance value of R2 can also display in degrees Celsius. AD584 output + 5V reference voltage UREF, after RP, R6 partial pressure to obtain the reference voltage U1, then OP07-inverting input terminal, an inverting input termination Uo. When Uo u1 when, op07 output high, by optical coupler electric heater 220v ac power supply is turned on, the to heat up. when t t1 uo u1, of becomes low, turn off power, forcing it lower temperature. ultimately climate control. open thermocouple, led emits light. if negative thermocouple ungrounded, once open-circuit fault meter will overload.




Leave Comment

characters left:

New Circuits

.