THREE-PHASE - BRUSHLESS - ELECTRONIC
REGULATION
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The new
series of alternators called ECO is the result of our long
experience in this sector and of diligent studies and
researches aiming to keep pace with the technological
development of an era where technology is the winning card.
Apart from guaranteeing the characteristics of the
preceding series, such as assuring a permanent short circuit
current above or equal to 3 times the nominal current, the ECO
series has also been improved. As far as its mechanical
components are concerned, the end-brackets have a new shape to
improve ventilation, the coupling to the prime mover is
simpler and the terminal boxes are bigger to simplify the
connection of the electric cables. As for the electric
components, the electronic regulators are always updated to
improve their performance and reliability, with the
possibility to interchange them with the previous ones.
All the ECO alternators have a fixed inductor with skewed
slots and a rotating inductor fitted with a damper cage
(except for the ECO3/4 and ECO28/4 alternators). The windings
have a 2/3 pitch in order to reduce the harmonic content of
voltage.
The entire series is manufactured according to
and complies with the most common specifications such as CEI
2-3, EN 60034-1, IEC 34-1, VDE 0530, BS 4999-5000; special
versions are available on request to meet specific
specifications and regulations.
APPLICATIONS
The new ECO series has been designed to meet both the
traditional requirements of the industry and the more
technological requirements of applications such as
telecommunications, cogeneration, army, aeronautics and marine
sectors.
RANGE
The ECO generators are
available with a 50/60 Hz frequency, with a single or double
support.
In order to couple them with the prime mover it
is possible to choose among a wide range of flanges and
couplings.
MECHANICAL STRUCTURE
The robust
mechanical structure permits easy access to the connections
and components during routine and extraordinary maintenance
check-ups.
The materials used for the manufacture of the
mechanical structure are the following: FeP12 steel for the
frame, C45 steel for the shaft and cast iron for the
end-brackets.
The standard degree of protection is IP21 or
IP23; upon the customer's request, other higher degrees of
protection, such as IP45, IP54, etc., are available.
INSULATION AND IMPREGNATION
lnsulation is
of class H standard. Impregnation is made with tropicalized
epoxy resins by dipping and dripping, whilst for the high
voltage parts by vacuum, so that the insulation level is
always very good. In the highpower models, the stator windings
undergo a further insulation. Special treatments for
particular environmental conditions are available on request.
REGULATION
The self-regulation is obtained
through an electronic regulator.
The regulator is fed by
an auxiliary winding which guarantees an almost constant
supply under any possible operating condition of the
generator.
The ECO series can be equipped with the new
interchangeable U.V.R.6 or S.R.7/2 regulator, ensuring the
same performance. The paragraph "REGULATORS" explains the
differences between these electronic devices.
VOLTAGE ACCURACY
The voltage accuracy is
±1% in static condition with any power factor and with speed
variation between -5% and +30% with reference to the rated
speed.
VOLTAGE REGULATION
The voltage can
be regulated by the "VOLT" potentiometer of the electronic
regulator. By connecting a 1OOKohms potentiometer in the
proper terminals it is also possible to obtain a remote
voltage regulation in a range of 5% of the rated voltage.
TRANSIENT VOLTAGE AND RESPONSE TIMES
At
full load and no load, at constant speed, there is a transient
voltage variation lower than 15% of the rated voltage. In such
conditions, the 3% voltage resetting will occur in 0.2 seconds
for powers up to 300 KVA, while for higher powers it will
occur in 0.3 seconds. Make reference to the user's manual for
more details.
OVERLOAD
The permissible
overloads are of 300% for 20 seconds, of 50% for 2 minutes and
of 10% for 1 hour every 6 hours of operation.
PARALLEL OPERATION
ECO alternators can
function in parallel among themselves, notwithstanding the
type of alternator, and/or in parallel with the mains provided
that they are equipped with the special device. This device is
available upon request for the alternators up to type 37,
while the alternators with a higher power are equipped with
this as standard equipment. In case of parallel with the mains
we offer the P.F.R. 96/1 electronic device which controls the
alternator's reactive current and/or power factor of the
alternator.
RADIO INTERFERENCE SUPPRESSION
The standard generators comply with the specification VDE
0875, degree "K" and with the basic safety requirements of the
European regulation on electromagnetic compatibility; by
applying the European standards EN 50081-1 and EN 50082-1, we
comply with the above mentioned regulation.
On request we
can supply filters for more restrictive specifications such as
MIL 461-462 D, etc..
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REGULATORS
The U.V.R.6 regulator (Universal
Voltage Regulator, sixth generation) and the S.R.7/2 regulator
(Simplified Regulator, seventh generation) may be used without
distinction in the ECO alternators without affecting their
performance. The two regulators are perfectly identical in
performance although they differ in the indications and
sensing.
S.R.7/2-G
The S.R.7/2-G regulator
is an advanced electronic regulator of small size and
economical price, even if it is very reliable.
This
regulator is equipped with a low speed and overload protection
with an adjustable intervention threshold, it works at 50/60
Hz, it has an adjustable voltage stability and it offers the
possibility for a remote voltage regulation.
U.V.R.6/1-F
The U.V.R.6 is built with the
same technology as the S.R.7/2-G and aside from having the
same performances and characteristics it also includes the
following specific functions:
1) possibility of
three-phase as well as singlephase sensing (we suggest to
choose this option in case of very unbalanced or non-linear
loads);
2) LED’s of self-diagnosis which indicate the
machine operating conditions instant by instant. By using the
optional device called S.P.D.96/A the information gathered may
be remote modified and made available; by doing so additional
protections and signalling are available.
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ACCESSORIES
U.F.P.-1
This
device is sensitive to the sudden speed losses of the main
engine in case of high torque and this problem occurs
especially with overfed diesel engines. The U.F.P.-1 device
triggers the electronic control U.V.R.6 or S.R.7/2 (they shall
be assembled together), thus considerably reducing the times
and thus increasing the capacity to reset the engine speed
thanks to a voltage/frequency multifunction characteristic of
the control.
S.P.D.96/A
The S.P.D.96/A
"remote protection warning device" is an electronic device
that, when combined with the U.V.R.6 voltage regulator, shows
how the alternator is working, from a distant location. lt
shows the following operating conditions:
overload: yellow
LED on
normal running: green LED on
low speed: red LED
on.
When one of the protections has tripped out, it is
possible to control other devices by means of an exchange
contact.
Furthermore S.P.D.96/A has an overvoltage and
overspeed detector. Each detector is connected to an exchange
contact which may be connected to external holding circuits
preventing these types of troubles. S.P.D.96/A is equipped
with a standard anodized aluminium box (DIN 43700 drilling)
allowing an easy fitting to the control panel.
R.B.D.-1
The R.B.D.-1 is an electronic
device which spots the presence of anomalies on the rotating
diode bridge (open diodes, short circuit, etc.); this
accessory is available on request. Said anomalies are
indicated by a red led as well as by the commutation of a
relay which, through an exchange contact of 2A 250V, allows
the user to obtain signals, alarms or shutdowns. Through an
external 12V battery, it is also possible to memorize the said
intervention.
P.F.R.96/1
The «Power factor
regulator» type P.F.R. 96/1 manufactured by MECC ALTE is a
piece of electronic equipment that when fitted to our
generators type ECO, allows control of the reactive current
and/or power factor of machines working in parallel with the
main, thus allowing the maximum utilisation of the plants.
P.F.R. 96/1 is housed in a DIN standard aluminium box
allowing easy fitting to the control panel.
ANTI
CONDENSATION HEATERS
Our whole range can be fitted
with anti condensation heaters of adequate power depending on
KVA.
Voltage for heaters must be specified when ordering.
RADIO INTERFERENCE SUPPRESSORS
MECC ALTE
generators comply with the main standards of radio
suppression.
To comply with even more restrictive
standards, upon the customer's request, it is necessary to fit
special filters in the generators, which MECC ALTE is able to
design and manufacture.
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THERMAL
PROTECTIONS
Upon the customer's request it is possible
to install one of the following devices as thermal protection:
-) PTC Thermistors
These components (which
are included in the standard equipment of the 37 - 40 -43 type
generators) are assembled in the heads of the stator windings
and they control the max. temperature. When the pre-set
temperature is reached, the thermistors emit a signal that can
be used by a trigger device (not included) to protect the
generator.
-) Thermal resistors PT100
The
resistance of this device varies proportionally to the
temperature of the winding where it is assembled. lf combined
with a thermostat (not included) it allows to set the
temperature to the desired value at which the whole protection
system trips out.
-) Bimetallic overload
protections
These devices have a NC contact that trips
immediately when a pre-set temperature is reached. lf the
temperature decreases, the contact resets automatically.
PARALLEL DEVICE PD 400
The PD parallel
device is a unified module allawing ECO generators to operate
in parallel among themselves with the tipical voltage drop or
with constant voltage. It also allows to operate in parallel
with the main eventually with the addition of P.F.R. 96/1. PD
is fitted as standard on generators series 40-43; for the
other series it is available on request.
INTAKE AIR
FILTERS
Environmental conditions for our generators
are extremely diversified. There are some very restrictive
standards concerning the protection degree of machines that,
in certain circumstances, must be applied. MECC ALTE studied a
protection system to be fitted on the machines to comply with
protection degrees IP 44 and IP45 of I.E.C. standards.
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