DST ObservAir Скачать руководство пользователя страница 10

 

 

18 

ObservAir

 Operating Manual 

Figure 10. 

Step 3 of filter tab replacement: Push the filter tab into the 

sensor until it is fully seated (notch should be flush with front panel) and 

tighten the thumbscrew firmly.

  

 
It  is  best  to  change  the  aerosol  filter  while  the  ObservAir  is  powered  off. 
However,  if  this  is  not  possible  or  inconvenient,  the  filter  may  also  be 
changed while the sensor is running. In this case, the LED button will flash 
red rapidly while the filter is removed  to indicate that an error is occurring. 
When the filter is replaced and tightened, the LED will go back to normal 
breathing  mode,  indicating  current  pollutant  concentrations.  If  the  LED 
flashes  red  rapidly  after  replacement,  check  that  the  filter  tab  has  been 
inserted fully into the sensor and is properly aligned in the slot: The notch 
on the tab should be directly above the solid white circle and flush with the 
front panel. The sensor will automatically detect the new filter and reset the 
ATN to 0. The ATN can also be reset manually (Section 3.2.4).  
 

3.4.

 

Battery charging 

 
Whenever  possible,  the  ObservAir’s  internal  battery  should  be  recharged 
using the included micro-USB cable and 2.1A power adapter. The sensor 
charges  fastest  when  it  is  powered  off  and  connected  to  the  2.1A  power 
supply:  a  depleted  battery  will  fully  charge  in  about  5  hours  in  this 
configuration. When the sensor is off and charging, the LED button shines 
a solid and turns off when charging is complete. The sensor can also be 
plugged into the charger while it is powered on and operating. The battery 
will  automatically  recharge  in  this  state,  but  at  a  lower  charging  current 
than when the sensor is powered off. When in normal operation, the LED 
button will briefly flash yellow once to indicate that a charging cable has 
been  successfully  connected.  The  sensor  will  also  trickle  charge  while 
connected to a computer’s USB port.  
 

Filter notch aligned with solid white mark. 

Notch tip flush with front panel. 

 

 

19 

ObservAir

®

 Operating Manual 

3.5.

 

Data collection from onboard SD card 

 
While the ObservAir is operating, data is written to the onboard SD card in 
real time as both a primary means of data collection and a reliable physical 
backup  when  wireless  data  transmission  protocols  are  implemented.  By 
default, the ObservAir creates a new data file every time it starts up. Each 
file 

represents 

data 

collection 

“mission”, 

and 

is 

called 

“DataXXX_YYMMDD_HHhMMm.txt”  where  XXX  represents  the  ObservAir 
unit’s  ID,  followed  by  the  date  and  time  of  startup.  The  SD  card  also 
contains a file called “Settings_DataXXX.txt” (where again XXX represents 
the  unit’s  ID)  that  contains  a  running  log  of  the  sensor’s  operational 
settings. A comprehensive overview of both files’ contents is provided below.  
 

3.5.1.

 

Settings file  

For each sensor mission, a new entry is appended to the settings file with 
the corresponding data file name as the header. Each entry in the settings 
file is composed of four sections:  

1.

 

Header:

 The name of the corresponding data file for which the listed 

sensor settings apply.  
 

2.

 

Sensor  Settings:

  This  field  contains  information  on  the  sensor’s 

configuration  and  operational  settings.  Fields  are  defined  below  and 
appear in the order listed.  

a.

 

SN 

Serial number. 

b.

 

ID: 

User assigned sensor ID. Default is the unit’s SSN.   

c.

 

Version:

 Hardware version number. 

d.

 

Firmware:

 Firmware version number. 

e.

 

GAS1:

 First optional gas sensor mounted onboard. 

f.

 

GAS2: 

Second optional gas sensor mounted onboard. 

g.

 

flowRate:

 Sample flow rate setting in units of ccm. Default is 100 

ccm.  

h.

 

samplePeriod: 

The data collection sample rate in seconds. Default 

setting is 2 seconds.  

i.

 

envComp:

  DST’s  proprietary  environmental  compensation 

algorithms  are  active  (‘True’)  or  pollution  concentration 
measurements are direct from the sensor(s) and uncompensated 
(‘False’). Default setting is True.  

j.

 

DLPFilter:

 Digital low pass (DLP) filter is active (‘True’) or turned off 

(‘False’). The DLP filter decreases measurement noise but increases 
the  minimum  90%  response  time  from  ~2  to  8  seconds  when 
monitoring BC concentrations. Gas measurement response time is 
minimally affected. Default setting is True. 

Содержание ObservAir

Страница 1: ...rational limits and warnings 11 3 Operating Instructions 13 3 1 Hardware overview 13 3 2 Interactive LED button Sensor display and control 14 3 2 1 Sensor startup 15 3 2 2 Default LED mode Pollutant c...

Страница 2: ...pport WiFi and USB communication protocols and include a 16GB removable SD card for onboard data storage Units may also be supplemented with an LTE LoRa or SigFox communication module and a GPS unit f...

Страница 3: ...collection area is 3 mm in diameter After the first filter the air flow passes through a second reference filter assembly that is identical to the first Since the air is filtered devoid of PM the int...

Страница 4: ...plication Operate the 7 ObservAir Operating Manual ObservAir for 12 to 24 hours in an environment that is free of the analyte gas es and average the voltage differential data collected over the entire...

Страница 5: ...technical specifications are summarized in the tables below All electrochemical cells are sourced from Spec Sensors Gas measurement performance specifications are adapted from data provided by the ma...

Страница 6: ...intervals 2 3 Operational limits and warnings Environmental limits Only operate the ObservAir within the conditions listed in Table 1 Temperature and relative humidity must remain between 5 to 40 C an...

Страница 7: ...nd may result in permanent damage to the unit and or harm to the user Please contact DST Technical Support at info dstech io regarding any problems with your unit that cannot be resolved with the inst...

Страница 8: ...llutants For every new start up event a new data file is created on the SD card txt file and is assigned a filename that contains the sensor s ID number and the start up time date Section 3 5 1 3 2 2...

Страница 9: ...f the ObservAir hold the LED button to cycle through the menu until the first red flash and release The sensor will flash red two more times to confirm that it is shutting down 3 2 6 Sensor alarms and...

Страница 10: ...ront panel 19 ObservAir Operating Manual 3 5 Data collection from onboard SD card While the ObservAir is operating data is written to the onboard SD card in real time as both a primary means of data c...

Страница 11: ...e ADC s raw count Full scale value is 8388607 d ATN Optical attenuation unitless e BC Black carbon in g m3 f T Temperature in C g RH Relative humidity in h FR Sample flow rate in ccm i VBAT Battery vo...

Страница 12: ...tings Figure 12 6 With the Serial Monitor configured ObservAir data is displayed in real time at the time interval set by the user Commands can also be sent to the sensor using the dialog box at the t...

Страница 13: ...8 to 1 2 Set flow rate calibration coefficient Table 7 ObservAir serial commands and descriptions 25 ObservAir Operating Manual 3 7 WiFi connection Provisioning WiFi credentials to the ObservAir allo...

Страница 14: ...1 Zero calibration of pollution sensors Each ObservAir comes with a zero calibration sheet but it is good practice to periodically verify the sensor s baseline performance especially before and after...

Страница 15: ...but clearly the calibration is only as good as the reference measurements collected 4 4 Leak check The ObservAir incorporates a monolithic design architecture that is more robust than traditional ins...

Страница 16: ...loading artifact is not static it depends on the emissions source e g biomass vs diesel atmospheric conditions seasonality and other factors Therefore filter loading correction algorithms should be c...

Страница 17: ...ing can be optimized to meet your needs For example if greater BC measurement resolution is desired at the expense of filter life the flow rate can be increased past the minimum value Conversely flow...

Страница 18: ...exhaust stacks vehicle tailpipes and other pollution sources When sampling emissions directly do not exceed the ObservAir s maximum temperature relative humidity range and pollution concentration rat...

Страница 19: ...If BC measurements are proportionally lower than the reference value then it is also possible but less likely that the ObservAir is leaking Given these potential error modes it is important to valida...

Страница 20: ...38 ObservAir Operating Manual Figure 14 Hard reset using the magnetic cover...

Отзывы: