Pizzi Instruments S.r.l products

The optical alignment collimator is an instrument produced by Pizzi Instruments and designed especially for monitoring movement at dam crests. The instrument, of notable optical-mechanical characteristics, with an objective lens of 80mm diameter and 60X magnification, allows optical alignment between two points considered fixed, this alignment defines a fixed vertical plane which allows the detection of movement of points in the structure aligned with it. The collimator is always positioned at the same station point thanks to special bases which allow repeat placing in the exact same position.

The operating principle of this instrument is very simple. Movement of the movable target carriage is by a motorization system inside the target itself. This system, conveniently connected by 3 wire cable to an appropriate ‘control device’, allows screen movement in the two opposite directions of the horizontal plane; a 3-digit mechanical index (each digit 15mm high), visible on the screen of the target, provides the measurement value via the optical collimator.

Voltage-current / RS485 input module PZ-8I is an input module with ModBUS RTU interface for 8 analog voltage or current signals in the ranges ± 2.5 Vdc, ± 10 Vdc and ± 20 mA with 16 bit resolution. The module’s auxiliary power supply can power all 8 current loops simultaneously. The current input with internal shunt can be selected via dip-switch. The insulation of the inputs with respect to the remaining low voltage circuits is 1,500 Vac.

During the installation phases of any type of instrument, when possible, it is always advisable to have a portable readout acquisition unit for the functional verification of sensors, both before and during all phases of installation. The availability of a read-out unit also during the operation of the system protects against the loss of information in the event of a failure of the automatic acquisition system. Various portable readout units are available today, depending on the type of sensor to be monitored and the characteristics required. There are individual readout units for analog and vibrating wire instruments as well as readout units that manage both types of sensors with the possibility of configuring individual channels and data storage.

The settlement plate is used to detect any settlement, subsidence and deformation of artificial embankments, both during construction and in the management phase. Simplicity of installation and reading, reliability, accuracy of measurement and very low cost, make it extremely popular for geotechnical and structural monitoring in all types of embankment. The instrument can be read manually or through a graduated “stadia”, or automated via electrical sensors and readable remotely with our hand-held units, portable units DEC5 and DEC3000 or our automatic acquisition unit DAC3000.

The BRS-type settling meter is used for checking settlements or subsidence in road embankments, foundations, dams etc.; it is preferred to other methods when the embankment, or the site to be checked, is already constructed; in this case the settling column can be installed by drilling. the system consists of a settling column made from a PVC pipe encased by a corrugated pipe carrying rings of magnetic material at predetermined distances. The probe detects its passage in the magnetic field of each ring by sending a signal to the readout unit connected by cable. The depth of interception is read on the cable (graduations in centimeters) supporting the probe.

The float level meter is mainly used for measuring the water level in channels, for the collection of leaks, in earthfill, concrete and RCC dams. A float of suitable shape and size follows the variations in level upstream of a weir; a LVDT extensometer is connected to the float and automatically measures its vertical movement, that is the variation of level. Level meters are available with ranges of 100mm, 200mm, 300mm; other ranges customizable on request.

The ultrasonic measuring system is often used for the measurement of levels, especially in dynamic regime channels; it is available in various measuring ranges, and can also be used in channels with small levels (up to one meter), always with acceptable accuracy. Easy to install and easy functional verification, it is particularly used in dams, both in tributary channels and in tunnels for the measurement of levels .

The wire deformometer is usually used to monitor and measure movements in landslides by measuring two points distant from each other. The instrument is made from the protected sensor in a sturdy aluminum box, by a non-deformable wire constantly kept in tense by a tensioning device and a fixing device to fix the other end of the wire to the measuring point.

Long-stroke vibrating wire extensometers, commonly called crackmeters, are used to measure the surface movements of structural cracks and joints, rock movements and ground deformations. They consist of a cylindrical body in stainless steel that houses the vibrating wire transducer and a sliding rod connected to the transducer itself through a spring. The two final parts of the instrument are equipped with anchoring devices with self-aligning spherical joints, for fixing over the slot or joint whose movements you want to measure. Optional accessories are available for correct installation even in particular applications, such as cracks at corners or edges, where normal fixtures cannot be used.