Emerson LTM-300 Manuel D’Utilisation

Level/Interface.  A second float may be added below the first    one, 

and the second output will be calibrated automatically.  The second 

time interval is measured in the same manner as the first and added 

to the first to derive the position  of the heavier float.

The same six inch dead zone applies to the measurement 

of the second level although the reasons are different.  This 

will typically correspond to a physical separation of the two 

floats by approximately three inches.  The float size, geometry, 

magnetic strength all play a factor in how close the two floats 

can get without interfering with each other.

The LTM-300 can be mounted to the side of a MagTech LG series level gage 
using a special mounting bracket and stainless steel hose clamps.  When 
mounting the transmitter to an LG series gage the active sensor region 
of the probe should fall within the centerline of the process connections 
on the gage.  If the transmitter deadband region is inside the centerline 
of the process connections the transmitter will not output an accurate 
measurement because the active region of the probe is too short.  When 
placing an order for a transmitter to accompany an existing gage it is 
important  to  indicate  the  style  of  the  gage,  the  temperature  and  the 
center-to-center  dimensions.    Calibration  of  the  probe  will  be  factory 
set along the active region of the probe; however, a field calibration may 
have to be performed to match the probe to the desired control room 
specifications.

If a transmitter is being purchased for an interface gage, the calibration 
for the probe should be done in the field to ensure a proper control room 

reading.  For long transmitters it may be desirable for the operator to have 
the electronics housing mounted at the bottom of the gage for easy access.  
THIS MUST  BE SPECIFIED AT TIME OF PURCHASE.  

Installation Note (European):
The cable entry devices and blanking elements of unused apertures shall 
be of a certified flameproof type, suitable for the conditions of use and 
correctly installed.

The  LTM-300  stand-alone  transmitter  comes  equipped  with  a  3/4” 
compression fitting, mounted approximately 6.00” below the electronics 
housing.  The fitting is placed in this area to ensure the transmitter is 
calibrated in the sensor tubes active region.  Refer to the stand-alone 
drawings for a visual description of the transmitter features.  Optional 
mounting configurations are available upon request.  

The magnetic float used in the stand-alone unit is designed to travel 
up the sensor tube with the change in fluid level.  If build-up of 
process or contaminates should restrict the movement of the float, 
the transmitter sensor tube will have to be cleaned or the float may 
have to be replaced with one that has a wider inside diameter.  The 
floats are designed to match the pressure and specific gravity for 
the process being measured and come in various materials ranging 
from stainless steel to kynar.

CAUTION:
During installation, do not attempt to twist or turn the head of the 
transmitter. Damage to the detector assembly may occur if the head 
is rotated . If the head is loose, please notify the factory.

The magnetic float can be changed out at any time to accommo-
date the processes being measured.  The float stop, located at the 
bottom of the transmitter, can be removed to allow the float to slide 
off the sensor tube.  

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PLEASE NOTE:
If using a transmitter configured for dual level output or interface 
measurements, remember to slide the float with the lightest grav-
ity range first.