GLX-RSS-2-300 WL User Manual
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GLX-RSS-2-300 WL Non-Contact Flow Meter
#set_an420_max=<value>
#set_ lvl_420_max=<value>
Change processing parameters:
Sensitivity level
- Configures the radar sensitivity level. The sensitivity level threshold is used by
the radar to determine whether the reflected signal is too low to detect any flow. If the instrument
is incorrectly reporting flow when there is no water in the channel, it’s necessary to increase the
value of this parameter.
#set_filter_len=<1-1000>
4 – 20 mA max.
– To configure the 4 – 20 mA output range, the maximum measured value which
will correspond to 20 mA analog output needs to be set. The value is set in the currently configured
measurement unit. Example: if values measured by the instrument are expected to be within the
range of 700 mm/s up to 1500 mm/s, it is recommended to configure the maximum value to slightly
above 1500 mm/s (for example 2000 mm/s). Alternatively, if the resolution is not critical, then the
maximum value for 4 – 20 mA output can be left to the instrument maximum of 15000 mm/s.
Level 4 – 20 mA min.
– To configure the 4 – 20 mA output range, the minimum measured value
which will correspond to 4 mA analog output needs to be set. The value is set in the currently
configured measurement unit. Example: if values measured by the instrument are expected to be
within the range of 700 mm up to 5000 mm, it is recommended to configure the minimum value to
slightly below 700 mm (for example 500 mm). Alternatively, if the resolution is not critical, then the
minimum value for 4 – 20 mA output can be left to the instrument minimum of 0 mm.
#set_lvl_420_max=<value>
Level 4 – 20 mA max.
– To configure the 4 – 20 mA output range, the maximum measured value
which will correspond to 20 mA analog output needs to be set. The value is set in the currently
configured measurement unit. Example: if values measured by the instrument are expected to be
within the range of 700 mm up to 5000 mm, it is recommended to configure the maximum value to
slightly above 5000 mm/s (for example 6000 mm). Alternatively, if the resolution is not critical, then
the maximum value for 4 – 20 mA output can be left to the instrument maximum.
#set_thld=<0-100>
SNR threshold
- The minimal Signal to Noise Ratio that is required to detect water flow. If the
actual measured SNR is lower than the threshold, the instrument will not report any flow. Setting
SNR threshold to a higher value will result with more robust measurements but may also result
with no measurements when the water is very smooth. Generally, the measurements with SNR
below 10 dB may be inaccurate, and measurements with SNR below 6 dB should not be trusted.
The SNR threshold should be set accordingly.
#set_thld_snr=<0-5120>
Filter length
- The length of the averaging filter, in number of readings, to smoothen the
measured values. The instrument performs 10 readings per second, so a filter length value of 50
will result in 5 second integration time. When using longer filter lengths, more measured values
are used for filtering, and the resulting data will be smoother. However, when the surface velocity
changes, it will take more time for the new measurement to be reported. Typically, this parameter
should be set to a value between 50 and 200. For highly turbulent water, longer filter length is
recommended.