Optosense LLC
USER MANUAL
Design department
SMALL-SIZE EXPLOSIVE GAS MEASURING
SENSOR MIPEX-02-X-X-X.1 X (RX)
ESAT.413347.005 UM
Revision 3.0
January 19th, 2017
Page 16 of 46
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6.4. Getting started
During first 40 seconds after the power is up sensor does not return the
measured concentration value (the value is displayed as “-1”, hex:
“8001”, see Table 13).
When the measurement range is exceeded, concentration value is displayed
as “32767” (hex: “7FFF”).
Sensor updates information about concentration every 1.28 ± 0.065 seconds.
Sending any command more often than one time per second (1 Hz) may
reduce sensor accuracy.
Switching on/off sensor is performed automatically upon feeding/disconnecting power supply.
After sensor is installed into end-user equipment check its status by sending <DATAE2>
command via UART interface:
for <DATAE2> command description see Appendix C.2.1;
for status bytes description and recommendations see Table 12.
Sensor span calibration and zeroing should be performed next. Methods of sensor span
calibration and zeroing are given in Appendix D.1.
6.5. Connecting multiple sensors to single UART line
It is possible to connect to single UART line up to 256 sensors assigning them net addresses
in range 00…FF. Sensor has net address 00 by default. To view and change its net address use
the following commands: <!**>, <NETON>, <NETOFF>, <%AABB>. For commands description
see Appendix C.2.5.
If sensor is used in combination with other devices on single UART line, any command text
must
contain sensor’s address prefix as “#AA”, where AA stands for sensor’s net address in
hexadecimal format
in range 00…FF. Thus, command text must be sent as <#AAX>, where X
stands for command text containing any number of characters in accordance with sensor
communication protocol (see Appendix C). Connection diagram of multiple sensors to single UART
line is shown on Fig. 6.