On-Line Electronic Liquid Density Monitor/Controller

A totally submerged plummet of constant volume functions as the density sensor for the Densitrol. The plummet is fastened by chains to a reference base and the whole assembly (plummet, chains and reference base) is housed within a chamber through which the liquid flows.

The plummet is weighted so that it assumes an equilibrium position at mid range with the weight of the chains equally supported by the plummet and reference base. The weight acting on the plummet will change as the plummet moves up or down in response to a change in liquid density. For each liquid density the plummet will assume a definite position corresponding to that density.

A Linear Variable Differential Transformer (LVDT) is mounted on the outside of the sensor chamber and monitors the plummet inside. The plummet includes a magnetic iron core. When the density changes, the plummet moves to a new position which is sensed by the LVDT. The voltage signal from the LVDT is a function of the plummet position and corresponds to the existing liquid density.


Range Limits

0.005 to 0.2 gm/cc

Densities 0.5 to 3.5 gm/cc

Viscosity Limit

50 cps max. @ Operating Temp.

For viscosity greater than 50 cps,

Consult factory


3% of range or 0.0002 gm/cc,

Which ever is greater

Flow Rate

Typical flow rates through

the chamber are 0.1 to 0.5 gpm


% of range

Speed of Response

Less than 30 seconds

Temperature Compensation

Typically 50F


   Standard:  4 to 20 mA DC

   Options:    1 - 5 or 10 - 50 mA DC 

                    or 5 to +5 mV DC

  To View or Download White Paper Technical Description of 

DENSITROLTechnology and Application

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PH: 215-355-1500  -  FAX: 215-355-7766

1020 Industrial Boulevard - Southampton, PA 18966 

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Last modified: November 29, 2005