Campbell Scientific EC155 CO2 and H2O Closed-Path Gas Analyzer and EC100 Electronics with Optional CSAT3A 3D Sonic Anemometer - Manual (Page 33)

EC155 CO
2
and H
2
O Closed-Path Gas Analyzer
7.4 Device Configuration Utility
The Device Configuration Utility software may also be used to change settings,
although ECMon is generally preferred because of its more user-friendly
interface. Device Configuration may be downloaded from the EC150 &
EC155 Support CD (pn 27007), or may be downloaded free of charge from the
Campbell Scientific website in the Support|Downloads section
( www.campbellsci.com/downloads ). Device Configuration requires a USB
driver to communicate with the EC100, similar to ECMon. See Section 7.3,
ECMon for notes on installing a USB driver.
After launching the Device Configuration Utility, the user should select
“EC100” from the list of device types. The EC100 electronics should be
connected to the PC with the EC100 USB cable (pn 26563) and the appropriate
USB port selected before connecting. Once connected, the settings tab
displays all the current settings. The Apply button must be clicked to save any
changes.
The Device Configuration Utility is also used to send an updated operating
system to the EC100 electronics. The Send OS tab gives directions on this
procedure.
8. EC100 Outputs
The EC100 outputs data in one of four types: SDM, USB, RS-485, or analog.
In general Campbell Scientific recommends that SDM be used if a Campbell
Scientific datalogger is responsible for data collection. However, RS-485
output is recommended over SDM if cable lengths exceed 100 meters. If a PC
is being used as the collection vehicle, USB and RS-485 are suitable outputs.
Analog output may also be used, however only CO
2
mixing ratio and H
2
O
mixing ratio will be output. More information regarding each output type is
provided in the sections below.
The EC100 synchronously samples the gas in the EC155 sample
cell and the CSAT3A sonic head. However, a delay induced by
the intake assembly must be accounted for to ensure maximum
covariance. The exact delay will depend on the length and size of
the intake tubing and the pump flow rate. See Appendix A or the
CPEC200 manual for details.
8.1 SDM Output
SDM (Synchronous Device for Measurement) is a Campbell Scientific
communication protocol that allows synchronized measurement and rapid
communication between a Campbell Scientific datalogger and multiple devices
including the EC155. Although nearly all of the Campbell Scientific
dataloggers support SDM, only the CR1000, CR3000, and CR5000 dataloggers
support the EC155.
To use SDM data output, connect an SDM cable from the EC100 (see Section
6.3, Wiring and Connections) to a CR1000, CR3000, or CR5000 datalogger.
On CR1000 dataloggers, the SDM protocol uses ports C1, C2, and C3. These
are multipurpose control ports that are SDM-activated when an SDM
instruction is used in the datalogger’s program. On CR3000 and CR5000
NOTE
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