Emerson Rosemount 5408 Reference Manual page 102

Service and Troubleshooting
November 2017
(1)
Symptom
Measured level is correct at 0% (4 mA) but
incorrect at 100% (20 mA).
Incorrect level when the product surface is
above the 50% level.
Measured value drops to zero level.
When the product surface is near the sloped
tank bottom, the transmitter enters alarm
mode.
1. = actual level
= reported level
90
Possible causes
Upper Range Value is not set
correctly.
Time
Strong double bounce echo
that is interpreted as the
product surface.
Time
Transmitter has locked on a
strong tank bottom echo.
Time
Reduction of projected surface
area close to sloping tank
bottom.
Time
Reference Manual
00809-0100-4408, Rev BA
Recommended actions
Check that the Upper Range Value matches the
100% (20 mA) level in the tank.
Enable the Double Bounce Handling function, see
"Handling strong double bounce echoes" on
page 111.
Verify the Reference Height is configured

correctly.
Enable the Tank Bottom Projection function, see

"Use tank bottom projection" on page
Enable the Bottom echo visible when tank is empty

parameter, see "Enable bottom echo visible
when tank is empty" on page
Verify the tank geometry parameters are

configured correctly (especially the Reference
Height and Bottom Offset).
If measurement in this region is not crucial,

increase the Empty Tank Detection Area, see
"Empty tank detection area" on page
Verify the Bottom echo visible when tank is empty

parameter is disabled, see
when tank is empty" on page
Service and Troubleshooting
108.
108.
200.
"Bottom echo visible
201.