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WARNING
!
It is absolutely forbidden to connect the unit to the public
mains and/or another electrical power source .
Access forbidden to area adjacent to electricity-
generating group for all non-authorized personnel.
!
WARNING
For the canopy generator sets provided with doors, the
following instruction shall be observed. During the normal
operation, the doors of the engine compartment and/or the
electrical box shall be kept closed, locked up if possible, as
they must be considered in all respects as protection barriers.
The access to the internal parts shall occur for maintenance
purposes only, by qualified personnel and, in any case, when
the engine is stopped.
The electricity-generating groups are to be considered electrical
energy producing stations.
The dangers of electrical energy must be considered together
with those related to the presence of chemical substances
(fuels, oils, etc.), rotating parts and waste products (fumes,
discharge gases, heat, etc.).
GENERATION IN AC (ALTERNATING CURRENT)
Before each work session check the efficiency of the ground
connection for the electricity-generating group if the distribution
system adopted requires it, such as, for example, the TT and
TN systems.
Check that the electrical specifications for the units to be
powered - voltage, power, frequency - are compatible with those
of the generator. Values that are too high or too low for voltage
and frequency can damage electrical equipment irreparably.
In some cases, for the powering of three-phase loads, it is
necessary to ensure that the cyclic direction of the phases
corresponds to the installation's requirements.
Connect the electric devices to be powered to the AC sockets,
using suitable plugs and cables in prime condition.
Before starting up the group, make certain no dangerous
situations exist on the installation to be powered.
Check that the thermal-magnetic switch (Z2) is in the OFF
position (input lever in downward position).
Start up the electricity-generating group, positioning the
thermal-magnetic switch (Z2) and differential switch (D) to ON
(input lever in upward position).
Before powering on the utilities, check that the voltmeter (N)
and frequency meter (E2) indicate nominal values; in addition,
check on the voltmeter change-over switch (H2) (where it is
assembled) that the three line voltages are the same.
+ In the absence of a load, the values for voltage and frequen-
cy can be greater than their nominal values. See sections on
VOLTAGE and FREQUENCY.
OPERATING CONDITIONS
POWER
The electrical power expressed in kVA on an electricity-
generating group is the available output power to the reference
environmental conditions and nominal values for: voltage,
frequency, power factors (cos ϕ).
There are various types of power: PRIME POWER (PRP),
STAND-BY POWER established by ISO 8528-1 and 3046/1
Norms, and their definitions are listed in the manual's
TECHNICAL SPECIFICATIONS page.
+ During the use of the electricity-generating group NEVER
EXCEED the power indications, paying careful attention when
several loads are powered simultaneously.
VOLTAGE
GENERATORS WITH COMPOUND SETTING
(THREEPHASE)
GENERATORS WITH CONDENSER SETTING
(SINGLEPHASE)
In these types of generators, the no-load voltage is generally
greater than 3–5% with respect to its nominal value; f.e. for
nominal voltage, threephase 400Vac or singlephase 230Vac,
the no-load voltage can be comprised between 410-420V
(threephase) and 235-245V (singlephase). The precision of the
load voltage is maintained within ±5% with balanced loads and
with a rotation speed variation of 4%. Particularly, with resistive
loads (cos ϕ = 1), a voltage over-elevation occurs which, with
the machine cold and at full load, can even attain +10 %, a
value which in any case is halved after the first 10-15 minutes
of operation.
The insertion and release of the full load, under constant rotation
speed, provokes a transitory voltage variation that is less than
10%; the voltage returns to its nominal value within 0.1 seconds.
GENERATORS WITH ELECTRONIC SETTING (A.V.R.)
In these types of generators, the voltage precision is maintained
within ±1,5%, with speed variations comprised from -10% to
+30%, and with balanced loads. The voltage is the same both
with no-load and with load; the insertion and release of the full
load provokes a transitory voltage variation that is less than
15%; the voltage returns to its nominal value within 0.2–0.3
seconds.
FREQUENCY
The frequency is a parameter that is directly dependent on the
motor's rotation speed. Depending on the type of alternator, 2
or 4 pole, we will have a frequency of 50/60 Hz with a rotation
speed of 3000/3600 or 1500/1800 revolutions per minute.
23
USING THE GENERATOR
M
37
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