DCA-45USI — GENERAL INFORMATION

DCA-45USI FAMILIARIZATION

Generator

The MQ Power Model DCA-45USI (Figure 4) is a 36 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:

zTachometer

zWater Temperature Gauge/ Alarm Lamp

zOil Pressure Gauge/ Alarm Lamp

zCharging Ammeter Gauge

zPre-Heat Lamp

zPanel Light

zPanel Light Switch

zIgnition/Preheat Switch

zFuel Gauge

zFuel Filter Water Level Alarm Lamp

Generator Control Panel

The “Generator Control Panel” is provided with the following:

zOutput Voltage Adjustment Knob

zFrequency Meter (Hz)

zAC Ammeter (Amps)

zAC Voltmeter (Volts)

zAmmeter Change-Over Switch

zVoltmeter Change-Over Switch

zVoltage Regulator

z3-Pole, 110 amp Main Circuit Breaker

Open Delta Excitation System

The DCA-45USI 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 fromtheparallelconnectionsofAtoB,AtoD,andCtoD.Thesethree phases of the voltage input to the voltage regulator are then rectified and are the excitation current for the exciter section.

Whenaheavyload,suchasamotorstartingorashortcircuitoccurs, 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

TheDCA-45USIispoweredbya4cycle,watercooled,turbocharged Isuzu BB-4JG1T diesel engine.This engine is designed to meet every performance requirement for the generator.ReferenceTable 1 for engine specifications.

InkeepingwithMQPower'spolicyofconstantlyimprovingitsproducts, the specifications quoted herein are subject to change without prior notice.

Output Terminal Panel

The “Output Terminal Panel” is provided with the following:

zThree 120/240V output receptacles (CS-6369), 50 amps

zThree auxilliary circuit breakers, @50 amps

zTwo 125 VAC output receptacles, (GFCI), 20 amps

zTwo GFCI circuit breakers @ 20amps

zFive output terminal lugs (3Ø power)

Control Box

The “Control Box” is provided with the following:

zAutomatic Voltage Regulator

zCurrent Transformer

zEmergency Relay

zOver-Current Relay

The basic controls and indicators for the DCA-45USI 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 within ±.5%. The electronic governor option decreases the frequency variation to within ±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.

PAGE 20 — DCA-45USI — OPERATION AND PARTS MANUAL (STD) — REV. #2 (04/22/05)

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Multiquip DCA-45US1 operation manual DCA-45USI General Information, Three auxilliary circuit breakers, @50 amps