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5 ACOUSTIC PROTECTION
For
maximum isolation effect, water lines and electrical conduit should also be isolated. Wall sleeves and rubber
isolated piping hangers can be used to reduce the sound transmitted through water piping. To reduce the sound
transmitted through electrical conduit, use flexible electrical conduit. EU and Local codes on sound emissions should
always be considered. Since the environment in which a sound source is located affects sound pressure, unit
placement must be carefully evaluated. Consult an acoustical engineer for critical
connections.
6 ELECTRICAL POWER SUPPLY
The mains power supply characteristics have to match the unit’s absorption. The mains power supply tension must
correspond to the nominal value ± 10%, with a maximum difference between the phases of 2%.
All power supply wiring must be sized and selected accordingly by the project engineer in accordance with standard IEC
60364. All wiring must comply with local code.
6.1
POWER CONNECTIONS
Protect the unit electric box power supply circuit with protection devices (not included in the supplied
equipment). Connect the line terminals with a three-core cable of a section which is appropriate to the unit
absorption. The switch and the fuses like all the power connections must comply with the regulations in force.
6.2
IMBALANCE BETWEEN THE SUPPLY TENSION PHASES
Do not run the electrical motors when the voltage unbalance between the phases is more than 2%.
Use the following formula to check:
% Imbalance = [(Vx – Vave) x 100/Vave]
Vave = (V1 + V2 + V3)/3
Vx = phase with greatest difference from Vave (without
regard to the sign)
IMPORTANT: If the mains voltage has an imbalance of above 2%, contact the company, which distributes the electrical
energy. If the unit functions with a unit voltage imbalance between the phases of above 2% the warranty is invalid.
6.3
UNIT VOLTAGE PHASING
It is important that proper rotation of the compressors be established before the unit is started. Proper motor
rotation requires confirmation of the electrical phase sequence of the power supply. The motor is internally
connected for clockwise rotation with the incoming power supply phases A-B-C.