Mosa CD4R90119003, Use And Maintenance Manual

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ENGLISH

ENGLISH

Access forbidden to area adjacent to electricity-

generating group for all non-authorized personnel.

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 frequency 

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 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.

M

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UsE As gEnErAtor

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WARNING

It is absolutely forbidden to connect the unit to the public 

mains and/or another electrical power source .

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.

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