2.13 Sound emission
AIRTOWER 3C AIRTOWER 4C AIRTOWER 5C
AIRTOWER
7.5C
Sound pressure lev‐
el [dB(A)]
69
70
70
70
Sound pressure level as per ISO 2151 and the basic standard ISO 9614-2, tolerance: ±3 dB(A) at
maximum machine working pressure
Tab. 16 Sound emission
2.14 Power Supply
Basic requirements
The machine is designed for an electrical supply according to National Electric Code (NEC)
NEC-670, particulary NFPA 79, edition 2014 , section 4.3. In the absence of any user-specified
alternatives, the limits given in these standards must be adhered to. Consult manufacturer for any
other specific power supply.
Three-phase
Do NOT operate package on any unsymmetrical power supply. Also do NOT operate package on
power supplies like, for example, a three-phase (open) delta or three-phase star with non-grounded
neutral.
The machine requires a symmetrical three-phase power supply transformer with a WYE configura‐
tion output as shown in Figure 2 and Figure 3. In a symmetrical three phase supply the phase an‐
gles and voltages are all the same.
Other power supplies are not suitable.
Fig. 2 Three-phase star (wye); 4 wire; grounded neutral
Fig. 3 Three-phase star (wye); 3 wire; grounded neutral
Further information Please contact an authorized KAESER service representative for options.
The electrical diagram 13.3 contains further specifications for electrical connection.
2
Technical Data
2.13 Sound emission
10
Operator Manual Screw Compressor
AIRTOWER 3C–7.5C Tri-Voltage
9_6917 34 USE
