Multiquip Portabel Generator (Standard) DCA-800SSK - Manual (Page 26)

PAGE 26 — DCA-800SSK (STD) — OPERATION AND PARTS MANUAL — REV. #4 (06/03/10)
DCA-800SSK — GENERAL INFORMATION
DCA-600SSK FAMILIARIZATION
Generator
The MQ Power Model DCA-800SSK is a 640 kW generator
that has been designed as a high quality portable (requires
a trailer for transport) power source for telecom sites, lighting
facilities, power tools, submersible pumps and other
industrial and construction machinery.
Engine Control Panel
The “Engine Control Panel” is provided with the following:
 Tachometer
 Water Temperature Gauge
 Oil Pressure Gauge
 Oil Filter Alarm Lamp
 Charging Ammeter Gauge
 Engine Warning Lamp Module
 Air Cleaner Indicator
 Engine Speed Switch
 Pre-Heat Button
 Pre-Heat Lamp
 Emergency Stop Button
 Battery Switch
Generator Control Panel
The “Generator Control Panel” is provided with the following:
 Output Voltage Adjustment Knob
 Frequency Meter (Hz)
 AC Ammeter (Amps)
 AC Voltmeter (Volts)
 Ammeter Change-Over Switch
 Voltmeter Change-Over Switch
 Panel Light
 Panel Light Switch
 MPEC Module
 Circuit Breaker ON/OFF Lamps
 Circuit Breaker ON Switch
 Circuit Breaker Reset Switch
 Pilot Lamp
Microprocessor Controlled Alarm System
The DCA-800SSK generator is equipped with various alarms
and LED status indicators. These alarms and status
indicators are provided to add safety to the generator when
operating under normal conditions. The DCA-800SSK
generator is designed to shutdown in the event of low oil,
high coolant temperature, low battery and other operation
conditions that may cause severe damage to the generator.
Open Delta Excitation System
The DCA-800SSK generator is equipped with the state of
the art "
Open-Delta" excitation system. The open delta
system consist of an electrically independent winding wound
among stationary windings of the AC output section.
There are four connections of the open delta A, B, C, and D.
During steady state loads, the power from the voltage
regulator is supplied from the parallel connections of A to B,
A to D, and C to D. These three phases of the voltage input
to the voltage regulator are then rectified and are the
excitation current for the exciter section.
When a heavy load, such as a motor starting or a short
circuit occurs, the automatic voltage regulator (AVR)
switches the configuration of the open delta to the series
connection of B to C. This has the effect of adding the
voltages of each phase to provide higher excitation to the
exciter section and thus better voltage response during the
application of heavy loads.
The connections of the AVR to the AC output windings are
for sensing only. No power is required from these windings.
The open-delta design provides virtually unlimited excitation
current, offering maximum motor starting capabilities. The
excitation does not have a "
fixed ceiling" and responds
according the demands of the required load up to the
horsepower of the engine.
Engine
The DCA-800SSK is powered by a 6 cylinder, water cooled,
turbocharged KOMATSU Model SA12V140 diesel
engine.
This engine is designed to meet every performance
requirement for the generator. Reference Table 2 for engine
specifications.
In keeping with Multiquip's policy of constantly improving
its products, the specifications quoted herein are subject to
change without prior notice.
The basic controls and indicators for the DCA-800SSK
generator are addressed on the following pages.
Electronic Governor System
The electronic governor system is made up of two parts, an
electronic controller that monitors frequency variation as the
load increases and decreases, and an electronic actuator
that controls the engine throttle. The frequency is regulated
at ±0.25 to help protect sensitive equipment.