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AIR BOOSTER 2
© STULZ SpA . – all rights reserved EN/10.2018/IT30I
4.3. Components
Structure
These machines are built using self-supporting panels made of painted galvanised sheet metal
to guarantee good corrosion resistance (not suitable for corrosive and saline environments). The
internal components of the unit can be accessed by simply removing the upper grill.
Fan
The fan is an infinitely variable axial fan with EC drive and PP coated sheet steel blades.
The bearings of the fans are lifetime lubricated and do not need maintenance.
4.4. Electrical components of protection and control
Contactors
They control the motors by operating with auxiliary voltage. They refer to IEC947-4-1 standards.
Automatic circuit breakers
They protect against short circuits and excessive motor current. They have adjustable thermal and
magnetic triggering devices.
Main switch
A main switch is located on the top of the unit, under the grille. It's used to disconnect main power
supply to the unit. When switched off, it interrupts power supply to the unit circuits from it downstream.
Temperature probes
Three NTC temperature probes are connected to analogue inputs of electronic controller for units
with controller on board and they have to be positioned in the lower part, in the middle and in the
high part of the rack.
Temperature probe 1
Temperature probe 2
Temperature probe 3
