How can we test a Flame sensor used in an Industril burner of Landis+Gyr or Honeywell Make.?

Question

Sometimes during startup cycle of the burner sequance controller Trips only after a flame is formed at that time doubt goes on flame sensor, but I dont know how to test this flame sensor, whether it is Good or not.

Answer 1

Your added explanation seems to be missing words or misusing them. The simple answer would be to use a replacement sensor and see if that works.
If you are using the UV flame sensor type, commonly called a purple peeper, should be testable by aiming it at a torch flame and checking the lead conductivity. Also check that it is clean.
If you are using the type that uses a thermocouple type wire that sits in the flame the output is so low, I don't know how to test it.