In the piezometer range produced by Pizzi Instruments, of particular importance is the Vibrating Wire Piezometer, a pressure transducer used for the measurement of neutral and interstitial pressures and also hydraulic levels. It consists of a watertight cylinder with a head of flexible stainless steel which functions as a membrane and deforms according to the difference between the external and internal pressure of the instrument. The instrument has a single body, fully-welded, without O-ring joints or connections, thus ensuring maximum and absolute waterproofing watertightness. Accurate and reliable over time, it is ideal for use in locations no longer accessible after installation.
Associated with these instruments, we offer:
The Casagrande Piezometer, used for measuring groundwater levels and pore pressures in soils of differing permeability. It consists of a filter head and one or two PVC tubes which connect the porous element to the surface.
Measurement of groundwater level is by Water Level Meter.
This is composed of:
– A probe with two noble metal contacts, isolated from each other by a circuit breaker
– An additional weighting head, mounted at the end of the cable.
– A winding reel which includes the devices to detect the probe’s contact with water.
– An inextensible flat tape or circular cable with graduations in mm or cm depending on model.
The Water Level Meter is an extremely reliable and durable instrument and requires little maintenance apart from replacement of the batteries when exhausted.
Another important instrument for the high precision measurement of small levels is the Floating Leakage Level System, mainly used for water level monitoring in weirs and upstream of calibrated sections. The measuring element is constituted by a linear sensor of the electric type, without sliding contacts.
This instrument has many advantages, including automation of measurement, possibility of remote signal transmission and insertion into centralized systems without requiring additional units for sensor interrogation or conversion of measurements.
The sensor, which is installed in an area of calm near the calibrated mouth, is not affected by changes in barometric pressure and records changes in levels perceived by the float.
For measuring water levels in tanks or open tanks, we offer our vibrating wire piezometers or piezo-resistive models. Transducers for measuring levels are produced with measurement ranges which can be selected between: 2 ÷ 100 meters (more on request) and with differing degrees of precision depending on the type of sensor chosen.
Possible applications of these instruments are varied, basically there are two differences between them:
1. Installation with the transducer immersed in the liquid whose level being measured, and inaccessible; this instrument is also referred to by us as external piezometer
2. Installation in a location always accessible (only the sensitive transducer membrane is in contact with the water). This instrument is also referred to as internal piezometer.
In addition to the piezometric sensor, Pizzi Instruments offers the following for measurement of liquid levels (particularly moving liquids):
– Level meters with radar sensor
– Level meters with ultrasonic sensor
These two sensors differ only in measuring range and precision, always proportional to full scale.
The radar sensor has a greater measuring range and allows greater precision.
For level measurements with even greater accuracy and larger measuring range, on request we offer level meters with digital quartz sensor.