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Three macroscopic variables are necessary to define the state of static air, each subject to direct measurement.
These variables are pressure, temperature and volume; the state of gas in the air with volume V, pressure
P and temperature T is defined by Boyles Law:
P*V =n*R*T. where n is the number of moles composing the gas and R is a universal constant.
The possible states of a gas with constant pressure and volume are expressed by the Gay-Lussac Law: with
constant pressure the volume of a gas increases as the temperature increases, or vice versa.
E xample:
Scale 99.9 mmH
2
O at each °C variable, the pressure varies by +/- 0.7 mm H
2
O
Scale 999 mmH
2
O at each °C variable, the pressure varies by +/- 3.4 mm H
2
O
Therefore, if the instrument is connected at variable temperatures, the pressure registered at the start will
definitely differ from final pressure.
This is normal and is not due to malfunctioning.
The MT digital instrument leaves the factory with a testing and calibration certificate.
Such calibration corresponds to that declared by the test instrument, according to international standards.
N.B. The test instrument is kept in the manufacturing plant.
Measurement uncertainty is assessed as “category B”
Ordinary and extraordinary maintenance of the digital pressure gauge and CALIBRATION, whose natural
validity is ONE YEAR, must be carried out by authorised personnel with equipment in compliance with
standards.
Calibration
Information: Pressure and Temperature
Rechargeable Battery
This device is equipped with a 3.7V rechargeable LITHIUM POLYMER battery.
To recharge the battery it should be connected to the PC using a USB cable or you can purchase a 230V
recharging cable separately.
When first turned on
On purchase the batteries are not fully charged.
Before using the instrument we recommend you charge the batteries for a maximum of 10 hours.
Chargin g.
1 Connect the battery charger connector to the micro USB socket on the lower part of the instrument, and
connect this to the USB port of any PC.
2 Connect the battery charger connector with the power supply unit to the micro USB socket on the lower part
of the instrument, and then connect the battery charger to a power socket.
3 Do not recharge the battery in an ATEX zone.
Us e
Batteries should never be exposed to high temperatures, or rather exceed working temperatures of -20°C to
+45°C.
To ensure an optimal service life, use at room temperature.
If used at both low and high temperatures its service life may be diminished.
Never dismantle the battery and never throw it on a fire as it may explode.
Never dispose of the battery as normal waste. Comply with local regulations on its disposal.
Voltage of charged battery 3.7V.
Working time Approximately 30 hours
Recharge from PC Recharge from AC 230V
Concepts and Battery Charging
