Punto de posicionamiento – Tecfluid LD61N User Manual
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1. WORKING
PRINCIPLE
The LD61N level switch is based on the variation of the natural resonant frequency of a 
vibrating fork, when it comes into contact with a liquid. 
This variation is detected by the internal electronics and is used to determine the state of 
the output . 
2. RECEPTION
The LD61N level detectors are supplied ready for installation and operation. 
They are supplied packed for their protection during storage and haulage. 
To handle the detectors, they should always be held by the head, never by the vibrating 
fork. 
The vibrating fork should not be modified or bent, as this can damage the detector beyond 
repair. 
3. INSTALLATION
The LD61N level switch can be 
mounted in any position. The more 
usual insertion points are shown in the 
figure 1. 
In positions 1 the LD61N acts as a 
maximum level detector. In positions 2 
the LD61N acts as a minimum level 
detector and in position 3 it acts as an 
empty pipe detector (for example, to 
protect a pump). 
If the LD61N is installed in a horizontal 
position it is recommended to install it 
with the tines vertical to avoid 
accumulation of substances, especially 
in the case of high viscosity liquids. 
To indicate the position of the tines the 
LD61N has a round mark on two of the 
flats of the nut. These marks should be 
in a vertical position when the detector 
is installed in a horizontal position. 
Punto de
posicionamiento
Positioning mark
Figure 1
