What does the null meter pointer of the model 3604 thermo unit indicate when the set point temperature is stable?

What does the null meter pointer of the model 3604 thermo unit indicate when the set point temperature is stable?

• A. It will point to maximum
• B. It will point to zero
• C. It will point to minimum
• D. It will blink

Answer: (B)

When a set point temperature is stable in the model 3604 thermo unit, the null meter pointer indicates zero. This is because the purpose of a null meter in a temperature control system is to show that there is no difference between the measured temperature and the set point temperature. When the system reaches stability and the actual temperature is equal to the desired set point, the null meter reflects this condition with a pointer at zero, indicating that there is no error or deviation that needs to be corrected. A pointer indicating maximum or minimum would suggest the system is far from the set point, while a blinking indicator could signify instability or fluctuation in the temperature readings. Thus, the correct answer demonstrates the desired equilibrium condition in the calibration process, confirming that the system is functioning correctly at the defined set point.

When a set point temperature is stable in the model 3604 thermo unit, the null meter pointer indicates zero. This is because the purpose of a null meter in a temperature control system is to show that there is no difference between the measured temperature and the set point temperature. When the system reaches stability and the actual temperature is equal to the desired set point, the null meter reflects this condition with a pointer at zero, indicating that there is no error or deviation that needs to be corrected.

A pointer indicating maximum or minimum would suggest the system is far from the set point, while a blinking indicator could signify instability or fluctuation in the temperature readings. Thus, the correct answer demonstrates the desired equilibrium condition in the calibration process, confirming that the system is functioning correctly at the defined set point.