Multiquip DCA25USI2XF, DCA25USIXF operation manual General Information, Familiarization

GENERAL INFORMATION

FAMILIARIZATION

Generator

The MQ Power DCA-25USIXF/DCA-25USI2XF Ultra-Silent generators (Figure 5) are 56 kW generators that are 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:

Tachometer

Water Temperature Gauge/ Alarm Lamp

Oil Pressure Gauge/ Alarm Lamp

Charging Ammeter Gauge

Pre-Heat Lamp

Panel Light

Panel Light Switch

Ignition/Preheat Switch

Fuel Gauge

Fuel Filter Water Level Alarm Lamp

Fuel Leak Detected Alarm Lamp

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, 60 amp Main Circuit Breaker

Output Terminal Panel

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

Two 250 VAC output receptacles (CS-6369), 50 amps

Two auxilliary circuit breakers, 250V @50 amps

Two 125 VAC output receptacles, (GFCI), 20 amps

Two GFCI circuit breakers, 125V@ 20amps

Five output terminal lugs (3Ø power)

Control Box

The “Control Box” is provided with the following:

Automatic Voltage Regulator

CurrentTransformer

Emergency Relay

Open Delta Excitation System

This 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 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

These generator’s are powered by two different types of diesel engines depending on the model of the generator. Both engines are 4 cycle, water cooled, direct injection types. The DCA25USIXF incorporates an ISUZU AA-4LE2 diesel engine, while the DCA25USI2XF incorporates an ISUZU BB-4LE2 diesel engine. Theseenginesaredesignedtomeeteveryperformancerequirement for the generator.Reference Table 2 for engine specifications.

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

The basic controls and indicators for the 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 6 ) as a guide for selecting proper extension cable size.

DCA25USIXF/DCA25USI2XF — OPERATION AND PARTS MANUAL — REV. #2 (07/26/11) — PAGE 17