Multiquip DCA45SSIU2 - Manual (Page 24)

PAGE 24 — DCA-45SSIU2 — OPERATION AND PARTS MANUAL (STD) — REV. #7 (06/13/07)
DCA-45SSIU2 — GENERAL INFORMATION
DCA-45SSIU2 FAMILIARIZATION
Generator
The MQ Power Model DCA-45SSIU2 (Figure 5) is a 26 kW
generator that is 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 Operating Panel
The “Engine Operating Panel” is provided with the following:
z Tachometer
z Water Temperature Gauge/Lamp
z Oil Pressure Gauge/Lamp
z Charging Ammeter Gauge
z Engine Speed Handle
z Pre-Heat Lamp
z Panel Light
z Panel Light Switch
z Ignition/Preheat Switch
Generator Control Panel
The “Generator Control Panel” is provided with the following:
z Output Voltage Adjustment Knob
z Frequency Meter (Hz)
z AC Ammeter (Amps)
z AC Voltmeter (Volts)
z Ammeter Change-Over Switch
z Voltmeter Change-Over Switch
z Voltage Regulator
z Over-Current Relay
Output Terminal Panel
The “Output Terminal Panel” is provided with the following:
z Three 250 VAC output receptacles (CS-6369), 50 amps
z Three auxilliary circuit breakers, 250V @50 amps
z Two 125 VAC output receptacles, (GFCI), 20 amps
z Two GFCI circuit breakers, 120V@ 20amps
z Five output terminal lugs (3Ø power)
Control Box
The “Control Box” is provided with the following:
z 3-Pole, 250 VAC, 110 amp Main Circuit Breaker
z Automatic Voltage Regulator
z Current Transformer
z Emergency Relay
Open Delta Excitation System
The DCA-45SSIU2 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 ot 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 DCA-45SSIU2 is powered by a 4 cycle, water cooled,
turbocharged Isuzu 4BG1
diesel engine. This engine is designed
to meet every performance requirement for the generator. Reference
Table 1 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-45SSIU2 generator
are addressed on the following pages.
Mechanical Governor System
The mechanical governor system control the RPM of the engine.
When the engine demands increase or decrease, the mechanical
governor system regulates the frequency variation to ±.5%. The
electronic governor option increases frequency variation to
±0.25%.
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 5 ) as a guide for selecting proper extension cable size.