Contents
What is the difference between sensor response time and sensor time?
Asymptotically means that the sensor reading/output will never truly reach the same temperature as the media. In terms of practical accuracy which is attainable in the real world, the sensor response time is taken as the time taken by the sensor to reach 99.3% of the measured temperature change.
What causes the O2 sensor circuit ” slow response “?
P0133 indicates the ECM senses that the O2 Sensor is not changing its voltage output quickly enough to the changing air-fuel ratio. Hence why the P0133 trouble code definition is O2 sensor circuit “slow response” because the circuit is not reacting quickly enough. What causes the P0133 code?
When is the second sensor reading closer to the real temperature?
Simply put, when the elapsed time between any two readings is equal to τ (sensor time constant), the 2nd sensor reading will always be 63.2% closer to the real temperature, no matter at which point in time the sensor values are taken. See Figure 1.
How is the response time different from the time constant?
Sensor Response Time = 5*τ (5x Time Constant) The Time Constant of a sensor is very different than its Response Time. In fact, the response time is exactly five times the time constant. Response Time is the time for the sensor reading to reach 99.3% of the total step change in measurand, or in this case the new temperature.
How is the time constant of a temperature sensor determined?
In a liquid or gas the time constant is strongly dependent upon the mass flow rate, which must be known when determining the time constant. For temperature sensors in meteorological applications, speed of air flow (wind speed) must defined when defining the time constant for temperature sensors.
How does a radiation shield affect sensor time?
In the case of meteorological air temperature measurement, solar radiation shields are used to limit the amount of error due to the sun’s irradiated heat onto the sensor in the form of global direct radiation, diffuse radiation and reflected radiation. Radiation shield design has a significant effect on the sensor time constant.