Answer / rambalaji

1. zirconia oxygen analyzers determine oxygen concentration using the conductivity of a zirconia ceramic cell. Zirconia ceramic cells only allow oxygen ions to pass through at high temperatures (750oC). With reference gas on one side and sample gas on the other, oxygen ions move from the side with the highest concentration of oxygen to that with the lowest concentration. The movement of ions generates an EMF (Electro Motive Force) which can be measured to determine the oxygen content

2. The sensor does not actually measure oxygen concentration, but rather the difference between the amount of oxygen in the flue gas and the amount of oxygen in the air. Rich mixture causes an oxygen demand. this demand Causes high voltage to build up due to transportation of oxygen ions through the sensor layer. Lean mixture causes low voltage since there is oxygen Excess. Sensor working in Nernst Principle
In flue gas side O2 is low : High Voltage

In flue gas side O2 is high : Low Voltage

High Concentration : O2 + 4 e  2O2 -

Low Concentration : 2O2 -  O2 + 4 e

0% O2 = 0.82 mv

5% O2 = 0.40 mv

21% O2 = 0 mv

Answer / manikandana

. When temperature increases the content of oxygen decreases.- principle.
Reference gas(span gas) instrument air 21% O2.
1% gas should provide from cylinder for cal purpose.

Explain why plc require in analog input 4-20amp & 0-10 volt?

0 Answers  

---

How to decrease opening & closing time of on/off valve?

0 Answers   UPL,

---

two common seiling liquid used in seal pots are:

1 Answers   Thermax,

---

What are the logic behind 2x2 and 2x3 logic and more when ask in interviews

1 Answers   Reliance,

---

anybody having Qatar Petroleum questions for instrument Technician offshore ....please send me

0 Answers  

---

tion 0,50,100% equql to voltage formula?

1 Answers  

---

what is loop1 and loop2 in MTS LT?

0 Answers   SPGC,

---

In vortex flow meter how can measure the frequency of vortex generated by vortex flow meter

4 Answers   Cadila,

---

GIVE BRIEF DESCRIPTION ABOUT "DCS"

2 Answers  

---

what is the differnce between PLC & DCS

7 Answers   TVS,

---

what is difference b/w the solinoid volve and autodrain?

3 Answers  

---

If P will increase then what will happen with PID?

1 Answers   Chettinad, Galfar, Mehran Sugar Mills,

---