User's Manual

3 Description of the instrument
6
Feature Value
Bluetooth
Range 20 m (free field)
(Varies depending on the capability of the
mobile terminal device used.)
Bluetooth type
LSD Science & Technology Co., Ltd
L series BLE module (08 May 2013) based on
TI CC254X chip
Qualified Design ID D030430
Bluetooth radio class Class 3
Bluetooth company 10274
3
Description of the instrument
3.1
Use
The testo 552 is a digital vacuum gauge for the precise measurement of
extremely small pressures in the vacuum range. This allows you to monitor the
evacuation (usually during commissioning) of refrigeration systems and heat
pumps.
With the testo 552, you can therefore measure the current pressure in a
refrigeration system, and thus gather information about the degree of
dehumidification and the removal of foreign matter (oils, foreign gases, etc.).
A vacuum gauge is always used in conjunction with a vacuum pump (generates
the vacuum). A manifold (analogue or digital) is also often used in order to
obtain controlled access to the refrigeration system.