Chapter 4
4-20 mA Signal Configuration / Operation
Airnet II Particle Sensor Operations Manual
Page 4-5
Configuration Commands
The following commands are available to use when setting 4-20 mA signal parameters.
?
Displays a command summary (a summary of the information in this table).
sta(tus)
If in PMS Operational mode, displays the current firmware version number, MAC
address, IP address, Multicast address, Net mask, gateway, and connection status. It
will also display current 4-20 mA parameters if that option was selected.
set sam(ple) x y
This function sets the minimum sample interval to
x
seconds and the maximum
sample interval (used when zero particles are detected) to
y
seconds.
This value is stored in permanent memory and is used by the instrument when it starts.
This value can be changed by means of the Ethernet interface (Facility Net). However,
when the Airnet II particle sensor is de-energized, the value set by the Ethernet
interface is replaced by the value in permanent memory. When the 4-20 mA option is
used, it always runs by the first sample interval.
set cumul n
This function selects between cumulative and differential data for the first two
configurable 4-20 mA outputs if that option is available.
If
n
equals 1, the data is cumulative and represents the number of particles detected
that are larger than the size specified for the channels.
If
n
equals 0, the data is differential and represents the number of particles detected
that are between the size specified for the first output channel and the size specified
for the second output channel.
set eos n
If
n
is set to 1 then the data in each channel is updated only at the end of each sample
interval and is held constant for the duration of the subsequent sample interval. If
n
is
equal to 0, the 4-20 mA channels are updated approximately every 100 milliseconds.
set raw n
If
n
is 1, the data in each channel is simply the number of particles detected. If
n
is 0,
the data is normalized by dividing the counts by the volume sampled. The output units
are counts per cubic foot.
