072-0500
Alphasense User Manual
OPC-R1 Optical Particle Counter
Issue 1
Alphasense Ltd
Page 30 of 33
February 2019
Sensor Technology House, 300 Avenue West, Skyline 120, Great Notley. Essex.CM77 7AA. UK
Tel: +44 (0) 1376 556700 - Fax: +44 (0) 1376 335899
Email: [email protected] - Web: www.alphasense.com
0x30
Sample Flow Rate Byte0
'Sample Flow Rate' is a float
variable occupying 4 bytes that
represents the sample flow rate in
ml/s.
0x30
Sample Flow Rate Byte1
0x30
Sample Flow Rate Byte2
0x30
Sample Flow Rate Byte3
0x30
Temperature Byte0
Temperature is unsigned 16bit
integer.
0x30
Temperature Byte1
0x30
Relative humidity Byte0
Relative humidity is unsigned 16bit
integer.
0x30
Relative humidity Byte1
0x30
Sampling Period Byte0
Sampling Period' is a float variable
occupying 4 bytes and is a
0x30
Sampling Period Byte1
measure of the histogram's actual
sampling period in seconds.
0x30
Sampling Period Byte2
0x30
Sampling Period Byte3
0x30
Reject count Glitch
'Reject count Glitch' is unsigned 8bit
integer.
0x30
Reject count Long
'Reject count Long' is unsigned 8bit
integer.
0x30
PM_A Byte0
PM_A is a float variable occupying 4
bytes. Units are ug/m3.
0x30
PM_A Byte1
0x30
PM_A Byte2
0x30
PM_A Byte3
0x30
PM_B Byte0
PM_B is a float variable occupying 4
bytes. Units are ug/m3.
0x30
PM_B Byte1
0x30
PM_B Byte2
0x30
PM_B Byte3
0x30
PM_C Byte0
PM_C is a float variable occupying 4
bytes. Units are ug/m3.
0x30
PM_C Byte1
0x30
PM_C Byte2
0x30
PM_C Byte3
0x30
Checksum Byte0
Checksum is unsigned 16bit integer.
0x30
Checksum Byte1
Read PM data (and
reset histogram)
0x32
0x32
0x31
Suggest that 10 ms be used as
delay between command byte and
following byte.