INFORMATION
US / WHISPER 15 ULTRA - Three Phase / December 2008 / Copyright © 2008 Mastervolt
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Fig. 11 AVR Trimmers (potentiometers).
The power comes from 12 wires that can be connected in
star, delta or combined double / star and double / delta
arrangements to take off different voltages. For 60Hz
applications the Whisper 15 ULTRA should be connected
in one of the following ways:
- As a 120/240Volt split phase generator by an
arrangement of the wiring in double DELTA.
-
As a 3 x 120V/208 Volt three phase generator when
the wires are arranged in double STAR. Here, 3x 208
Volt is available between the phases while 120 Volt is
available between every phase and neutral.
Further technical data on the connections of the alternator
can be found in drawings and diagrams in this manual.
The three phase synchronous alternator is directly
coupled, one bearing, brushless, rotating field design, 12
wire, four pole (1800 RPM) and regulated by an Automatic
Voltage Regulator (AVR).
Residual magnetism causes a small voltage over the
stator windings and allows a current to flow in the
windings, which is magnified because of the feed back
effect between rotor and stator. The field windings in the
rotor are short-circuited over a diode to rectify the current.
A capacitor over an additional winding in the stator which
is at an angle with the power-winding keeps the voltage
stable within 5 % at the specified rpm and provides voltage
fall off with speed, preventing over-excitation at low engine
speeds and softening the effect of load switching to relieve
the burden on the engine.
Further technical data on the design of the alternator can
be found in drawings and diagrams in this manual.
2.5.2 Engine
The Whisper 15 ULTRA Three Phase generating set is
based on the Mitsubishi S4L2 4 cylinder diesel engine.
The engine is indirectly injected. The engine is water
cooled and the cooling liquid is cooled by a heat
exchanger and raw water. The heat exchanger and all
other parts which are in direct contact with the raw (sea)
water are made of seawater resistant material like naval
brass and gunmetal.
The engine has been specially adapted for the Mastervolt
application and is very different from the standard engine
supplied for industrial applications!
The engine fulfills EPA emission standards and is certified
and labelled as such.
2.5.3
Digital Diesel Control system
The standard electrical engine control system is 12 Volt
negative earth, non earth return (ungrounded) is available
as optional. Check your identification data to determine
which system is applied. The system is designed
according to the "energise to run" system. The Digital
Diesel Control is a very advanced microprocessor based
full automatic system. Besides automatic start the system
offers many monitoring options. Refer to the separate
Digital Diesel Control users manual.
The microprocessor unit is located in the black box on top
of the alternator (see figures 3 and 8)
2.5.4
Battery charger
On the engine is an alternator generating 50 Amp 12V.
This current is rectified to charge the battery. The voltage
is regulated at ±14.4V.
2.5.5
Alarms and shut down
In the event of malfunctioning this will be indicated by the
failure LED, details will be shown on the display and the
engine will be shut down. There are three functions
guarded: oil pressure, oil temperature and exhaust
temperature.
Exhaust temperature too high indicates the cooling water
to be blocked.
All alarm switches are closed when no malfunction occur.
A contact is cut in the event of an alarm. This means that
the generating set will not work when the alarm switches
are broken or there is a loose wire. The system therefore
is intrinsically safe. The panel will display details about the
alarm.
2.5.6 Monitoring
Refer to the operating of the Digital Diesel Control
2.5.7 Control
The generating set can be operated by push buttons on
the panel on the alternator or by the remote control. By
pushing the START button the control system is activated