General Information - MULTIQUIP Power WhisperWatt DCA45SSIU4 Operations & Parts Manual

GENERATOR
The MQ Power Model DCA45SSIU4 generator (Figure 3) is
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 operatIng panel
The "Engine Operating Panel" is provided with the following:
„ Tachometer
„ Water Temperature Gauge
„ Warning Lamp
„ Pre-Heat Lamp
„ Oil Pressure Gauge
„ Charging Ammeter Gauge
„ Fuel Level Gauge
„ Panel Light/Panel Light Switch
„ ECU Controller
„ Engine Speed Switch
generator Control panel
The "Generator Control Panel" is provided with the following:
„ Frequency Meter (Hz)
„ AC Ammeter (Amps)
„ AC Voltmeter (Volts)
„ Ammeter Change-Over Switch
„ Voltmeter Change-Over Switch
„ Voltage Regulator
„ 3-Pole, 110 amp Main Circuit Breaker
„ "Control Box" (located behind the Gen. Control Panel)
• Automatic Voltage Regulator
• Current Transformer
• Over-Current Relay
• Starter Relay
• Voltage Selector Switch
oUtpUt termInal panel
The "Output Terminal Panel" is provided with the following:
„ Three 120/240V output receptacles (CS-6369), 50A
„ Three auxiliary circuit breakers, 50A
„ Two 120V output receptacles (GFCI), 20A
„ Two GFCI circuit breakers, 20A
„ Five output terminal lugs (3Ø power)
page 16 — DCa45SSIU4 60 hz generator • operatIon anD partS manUal — rev. #1 (10/24/13)

generaL infOrMatiOn

open Delta exCItatIon SYStem
The DCA45SSIU4 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.
ENGINE
The DCA45SSIU4 is powered by a 4 cylinder, water
cooled, direct injection, turbocharged ISUZU 4JJ1T diesel
engine. This engine is designed to meet every performance
requirement for the generator. Reference Table 2 for engine
specifications.
In keeping with MQ Power's policy of constantly improving
its products, the specifications quoted herein are subject
to change without prior notice.
eleCtrIC governor SYStem
The electric governor system controls the RPMs of the engine.
When the engine demand increases or decreases, the
governor system regulates the frequency variation to ±.25%.
extenSIon CableS
When electric power is to be provided to various tools or
loads at some distance from the generator, extension cords
are normally used. Cables should be sized to allow for
distance in length and amperage so that the voltage drop
between the generator and point of use (load) is held to
a minimum. Use the cable selection chart (Table 6) as a
guide for selecting proper extension cable size.