Emerson Rosemount 5402 Reference Manual page 204

Service and Troubleshooting
October 2018
190
The level value drops to a
lower value when the
product surface is close to
the antenna.
The transmitter displays
"measurement error" and
activates Measurement
Alarm
Alarm when the product
level is close to the antenna.
The measured level is
unstable.
Reference Manual
00809-0100-4026, Rev KC
May be caused by:
Product level within the Hold Off region, that

is outside the approved measuring range, and
the transmitter is picking up secondary signal
reflections
Action:
Avoid filling the tank to levels close to the

antenna.
Move the transmitter to increase the distance

between maximum product level and
antenna, if possible.
Activate the Full Tank Handling function if

measurements up to the antenna are
required, see "Full tank handling" on
page 261 and 267.
May be caused by:
Product level within the Hold Off region, that

is outside the approved measuring range
Action:
Avoid filling the tank to levels very close to the

antenna.
Move the transmitter to increase the distance

between maximum product level and
antenna, if possible.
Activate the Full Tank Handling function if

measurements up to the antenna are
required, see "Full tank handling" on
page 261 and 267.
May be caused by:
An empty tank with the Amplitude Threshold

too low
Product surface is close to a registered False

Echo
Action:
Create a new ATC, see "Echo tuning" on

page 109.
Service and Troubleshooting