Specifications

240
Reference Manual
00809-0100-4026, Rev HA
Appendix C: Advanced configuration
November 2014
Advanced Configuration
Empty tank detection area
The Empty Tank Detection Area is the range within a lower limit of 16 in.
(400 mm) and a higher limit of 39 in. (1000 mm) above the tank bottom. If the surface echo is
lost in this region, the tank is considered empty (the device enters Empty Tank State) and the
transmitter presents a zero level reading.
If the tank is empty, the transmitter searches double the Empty Tank Detection Area for the
product surface. When a new echo is found, it is considered to be the product surface.
It is important that there are no disturbances in this area, but if there are, they may need to be
filtered out.
This function requires the Bottom Echo Visible function to be disabled. The current Empty Tank
Detection Area value is shown in Advanced Setup in RRM and can be adjusted manually, if
required. See “Empty tank detection area” on page 244.
Bottom echo visible
Only set this parameter if the bottom echo is visible. Setting this parameter will use the bottom
echo as a disturbance echo to facilitate tracking of weak surface echoes close to the tank
bottom.
Check that the gauge detects the tank bottom when the tank is empty before activating this
function. See “Bottom echo visible” on page 243.
Tank bottom projection
This function handles situations close to the tank bottom and may enhance measurement
performance in the tank bottom region. In this region, the signal from the actual tank bottom
may be significantly stronger than the measurement signal from the product surface, in some
situations.
Extra echo
Extra Echo Detection is used for tanks with domed or conical bottom types and when there is no
strong echo from the tank bottom when the tank is empty and an echo beneath the actual tank
bottom can sometimes be seen. See “Extra echo function” on page 245.
Level alarm is not set when tank is empty
If the echo from the product is lost in the area close to the tank bottom (Empty Tank Detection
Area), the device enters Empty Tank State and triggers an alarm. Two types of alarms are
triggered:
 Invalid Level (can be seen in the Diagnostics window)
 The Analog Output enters Alarm Mode