Emerson Transmitter 350 Mode D’Emploi

A stilling well may be used along with the 

transmitter inside the tank. Stilling-well is a pipe 

external to the sensor probe and float encasing the 

entire assembly protecting it from surface agitation 

or from physical damage due to the length of the 

sensor probe.  A depiction of a transmitter with a 

stilling well is provided below.

Figure 4.  Transmitter with a Stilling-well

When a stilling well is used, care should be 

exercised when installing the tube to center it in 

the chamber so that the float can freely travel 

the entire length of the probe.  Stilling wells are 

Optional Features that are available with the    

LTM-350 but NOT the LTM-250 are:

1. HART Protocol, which enables:

a. A second digital output proportional to 

an interface level (requires a second 

float of different specific gravity)

b. A digital temperature output that 

reflects the liquid temperature.

c. Advanced diagnostics and features 

highly beneficial for commissioning, 

troubleshooting or monitoring.

Up to two floats may be used with the LTM-350 

only.  The second float will typically sense the 

interface level (the heavier of the two fluids) in the 

tank.  The specific gravity of the second float will be 

such that it can be totally immersed in the lighter 

fluid.  The drawing below shows a transmitter with 

dual floats, one for total level and the other for 

interface level (also available with various process 

connections).

Figure 5.  Dual Output Transmitter

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