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When using residual current operated circuit brakers, be
sure to use a high speed type 300 mA rated residual
operating current.
5.3. Phase unbalance
In a three-phase system, the excessive unbalance between the
phases is the cause of the engine overheating. The maximum
permitted voltage unbalance is 3%, calculated as follows:
Imbalance % =
Vx = phase with greatest imbalance
where:
Vm = average of the voltages
Example:
the three phases measure 383, 386 and 392 V respectively.
383 + 386 + 392
The average is:
3
The unbalance percentage is:
(392 – 387) * 100
3
less than the maximum allowed (3%).
6. oPerator's rePonsibiLities
It is essential that the operator is appropriately trained and becomes
familiar with the system before operating the unit. In addition to
reading this manual, the operator must study the microprocessor
operating manual and the wiring diagram to understand startup
sequence, operation, shutdown sequence and operation of all the
safety devices.
During the unit initial startup phase, a technician authorized by the
manufacturer is available to answer any questions and to give
instructions as to the correct operating procedures.
The operator must keep a record of operating data for every installed
unit. Another registration must also be kept for all the periodic
maintenance and assistance activities.
If the operator notes abnormal or unusual operating conditions, he is
advised to consult the technical service authorized by the
manufacturer.
If the unit is switched off, the compressor oil heater cannot
be used. Once the unit is reconnected to the mains, leave
the compressor oil heater charged for at least 6 hours
before restarting the unit.
Failure to observe this rule may cause damage to the
compressors due to excessive accumulation of liquid
inside them.
This unit represents a substantial investment and deserves the
attention and care to keep this equipment in good working order.
However, during operation and maintenance it is essential to observe
the following instructions:
• do not allow unauthorized and / or unqualified personnel to
access the unit;
• It is forbidden to access the electrical components without
having opened the unit main switch and switched off the
power supply;
DEIMHP0140521_00EN
18
(Vx – Vm) * 100
Vm
= 387 V
= 1.29
1.29 %
• It is forbidden to access the electrical components without
using an insulating platform. Do not access the electrical
components if water and/or moisture are present;
• Verify that all operations on the refrigerant circuit and on the
components under pressure are carried out exclusively by
qualified personnel;
• The replacement of the compressors must be carried out
exclusively by qualified personnel;
• Sharp edges and the surface of the condenser section could
cause injury. Avoid direct contact and use adequate pro-
tection device;
• Do not introduce solid objects into the water pipes while the
unit is connected to the system;
• It is absolutely forbidden to remove all protections of moving
parts.
In case of sudden stop of the unit, follow the instructions on the
Control Panel Operating Manual which is part of the on board
documentation delivered to the end user.
It is strongly recommended to perform installation and maintenance
with other people.
Avoid installing the unit in areas that could be dangerous
during maintenance operations, such as platforms without
parapets or railings or areas not complying with the
clearance requirements around the unit.
7. MaintenanCe
Personnel working on the electrical or the refrigeration components
must be authorized, trained and fully qualified.
Maintenance and repair requiring the assistance of other skilled
personnel should be carried out under the supervision of the person
competent in the use of flammable refrigerants. Any person
conducting servicing or maintenance on a system or associated parts
of the equipment should be competent according to EN 13313.
Persons working on refrigerating systems with flammable
refrigerants should have competence in safety aspects of
flammable refrigerant handling supported by evidence of
appropriate training.
No person carrying out work in relation to a refrigerating system which
involves exposing any pipe work shall use any sources of ignition in
such a manner that it may lead to the risk of fire or explosion. All
possible ignition sources, including cigarette smoking, should be kept
sufficiently far away from the site of installation, repairing, removing
and disposal, during which refrigerant can possibly be released to the
surrounding space. Prior to work taking place, the area around the
equipment is to be surveyed to make sure that there are no flammable
hazards or ignition risks. "No Smoking" signs shall be displayed.
Always protect the operating personnel with personal protective
equipment appropriate for the tasks to be performed. Common
individual devices are: Helmet, goggles, gloves, caps, safety shoes.
Additional individual and group protective equipment should be
adopted after an adequate analysis of the specific risks in the area of
relevance, according to the activities to be performed.
electrical
Never work on electrical components until the ma-
components
chine's main power supply has been cut off with the
main switch on the electrical panel. Wait 10 minutes
after cutting off the machine's power supply before
opening the electrical panel, to prevent the risk of
high voltage due to firing of the capacitors.
EWYT~CZ / EWAT~CZ
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