Infrared Temperature Measurement Module P31-A

Introduction

◆Product application

- Face recognition machine
- attendance machine
- Temperature door
- security check

 

  ◆Serial Communication

	VT YP31-A
Temperature Range	Body temperature mode 32~42.5 ℃, surface mode 0~300 ℃
Accuracy	±0.3℃ for temperature mode ±1℃ or ±1% m.v for surface mode
Digital Resolution	0.1 ℃
Measurement Cycle	0.5 s
Supply Voltage	4.5~5.5V
Working Current	＜2 mA
Output Signal	UART, II2C
Communication Level	TTL 3.3 V
Temperature  Compensation	10.0 ~ 40.0 °C
Angle Of View	12.4度
Spectral Response	5.5-14 μm
Length, Width And Height	34×26×25 mm
Range Of Working Temperature	0-50 ℃
Working Humidity Range	0-95%RH  no condensation

 

◆Packet Structure

Data packet header --- MSB --- LSB --- SUM --- terminator
The header of the data packet is the command symbol: 0x4C, 0x4D, 0x66, 0x53, 0x54 MSB: 
 high byte with 16bit data    LSB: low byte with 16bit data
SUM: Packet header + MSB + LSB (SUM is the low byte of the summation) terminator: 0x0D

 

◆Function Example

1.Use the emissivity value stored in the module to read the temperature value of the 
target object

-Example :
PC sends commands through the serial port : 0x4C, 0xAA, 0x55, 0x4B, 0x0D
The module returns data through the serial port : 0x4C, 0x14, 0x2A, 0x8A, 0x0D
0x14 and 0x2A are the data of the measured target temperature value, the calculation. 

-Method is as follows:
a. Convert 0x142A to a floating point number to get 5162;
b. 5162/16 = 322.625
c. 322.625-273.15 = 49.475
The target temperature is 49.475°C

2.Artificially set the emissivity value and read the temperature value of the target object

The artificially set emissivity value is placed in LSB bytes. The data range is 
10~100 (0x0A~0x64, representing emissivity 0.10~1.00). Other settings beyond 
the range are invalid. The module will use the emissivity value of 95, that is, 
emissivity 0.95, for calculation.        

-Example:
PC sends commands through the serial port :  0x4D, 0xAA, 0x64, 0x5B, 0x0D
 (Set the emissivity value to 100, 0x64, that is, the emissivity is 1.00)
The module returns data through the serial port :
0x4D, 0x14, 0x2A, 0x8B, 0x0D temperature calculation method is the same as above. 
49.475°C

3.Read the internal temperature value of the module
     
-Example :
PC sends commands through the serial port :  0x66, 0xAA, 0x55, 0x65, 0x0D
The module returns data through the serial port : 0x66, 0x12, 0xC3, 0x3B, 0x0D
The temperature calculation method is the same as above. 27.037°C

 

4. Change the emissivity value stored in the module

The emissivity value to be written into the module is placed in LSB bytes, and the 
data range is 10~100 (0x0A~0x64, representing the emissivity 0.10~1.00) 
Other settings beyond the range are invalid, and the default emissivity value of the
 module is 95, that is, the emissivity is 0.95. the module returns the actual written 
emissivity value.          

-Example 1 :
 PC sends commands through the serial port :  0x53, 0xAA, 0x64, 0x61, 0x0D
(The emissivity value to be written into the module storage is 100, a normal value 
within the range, 0x64, that is, the emissivity is 1.00)
The module returns data through the serial port : 0x53, 0x55, 0x64, 0x0C, 0x0D
 (The actual written emissivity value is 100, 0x64, that is, the emissivity is 1.00)

-Example 2 :
PC sends commands through the serial port :  0x53, 0xAA, 0xFF, 0xFC, 0x0D
 (The emission coefficient value to be written into the module storage is 255, the value
 is not within the range, 0xFF, the writing is unsuccessful, and the module emits by 
default a factor value of 95 gives an emissivity of 0.95
The module returns data through the serial port : 0x53, 0x55, 0x5F, 0x07, 0x0D
(The actual written emissivity value is 95, 0x5F, that is, the emissivity is 0.95)

5. Read the emissivity value stored in the module

-Example :
PC sends commands through the serial port :  0x54, 0xAA, 0x55, 0x53, 0x0D
The module returns data through the serial port :   0x54, 0x55, 0x64, 0x0D, 0x0D
(The emissivity value stored by the module is placed in the LSB byte, the current stored emissivity 
value is 100, 0x64, that is, the emissivity is 1.00)

 

◆ Dimensions

 

◆ Pin Diagram