Showing posts with label Sensors. Show all posts
Showing posts with label Sensors. Show all posts
Sunday, 15 January 2017
Advantages Disadvantages of RTD Thermocouple Thermistor Temp IC Sensors
Hi Greeting,
Friends we always come across various temperature sensors like RTD, Thermocouple, Thermistor, temperature sensing IC’s while doing automation of process plants. It’s very essential to know about advantages & disadvantages of the entire sensors so that we can select them with ease.
So let’s start with Thermocouple.
Thermocouple:
Advantages of Thermocouple:
- Self Powered
- Simple
- Rugged
- Inexpensive
- Wide Variety
- Wide Temp Range
Disadvantages of Thermocouple:
- Non Linear
- Reference Required
- Low Voltage
- Least Stable
- Least Sensitive
RTD:
Advantages of RTD:
- Most Stable
- Most Accurate
- More Linear than Thermocouple
Disadvantages of RTD:
- Expensive
- Current Source Required
- Small ∆R
- Low absolute Resistance
- Self heating
Thermistor:
Advantages of Thermistor:
- High Output
- Fast
- Two wire ohms measurement.
Disadvantages of Thermistor:
- Non Linear
- Limited Temperature Range.
- Fragile
- Current Source required.
- Self heating
IC Sensors:
Advantages of IC Sensor:
- Highest Output.
- Inexpensive.
- Most linear.
Disadvantages of IC Sensor:
- T< 200C.
- Power supply required.
- Slow.
- Limited Configuration.
- Self heating
Monday, 31 October 2016
Humidity Sensors with SHT11
Output of both sensors are combined and connected on 14-bit ADC and a serial interface on a single chip the same. The sensor output signal aimlessly good with a fast response time. SHT11 Humidity Sensor was calibrated at room denagn humidity accurately using as a reference hygrometer. Calibration coefficients have been programmed into the OTP memory. Coefficient will be used to Calibration output from the sensor during the measurement process.
 |
| Humidity Sensors Diagram Block |
Sensor system used to measure temperature and humidity are SHT11 Humidity Sensors with 5 Volt voltage source and bidirectonal 2-wire communication. This sensor system has a data path that is used for addressing and reading the command data.
Data collection for each measurement is done by giving orders addressing the microcontroller. Foot serial data that is connected with microcontroller provides a command addressing the pin Data SHT11 Humidity Sensors "00,000,101" to measure relative humidity and "00000011" for temperature measurement. SHT11Humidity Sensor provide humidity and temperature output data on data pins alternately in accordance with the given clock microcontrollers for sensor to work. Sensor SHT11 have ADC (Analog to Digital Converter) in it so that the output data is configured SHT11 Humidity Sensors in the form of digital data and requires no external ADC in data processing on the microcontroller. SHT11 Humidity Sensors data retrieval scheme can be seen in the picture below.
Data collection for each measurement is done by giving orders addressing the microcontroller. Foot serial data that is connected with microcontroller provides a command addressing the pin Data SHT11 Humidity Sensors "00,000,101" to measure relative humidity and "00000011" for temperature measurement. SHT11Humidity Sensor provide humidity and temperature output data on data pins alternately in accordance with the given clock microcontrollers for sensor to work. Sensor SHT11 have ADC (Analog to Digital Converter) in it so that the output data is configured SHT11 Humidity Sensors in the form of digital data and requires no external ADC in data processing on the microcontroller. SHT11 Humidity Sensors data retrieval scheme can be seen in the picture below.
Subscribe to:
Posts (Atom)