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GENERAL INFORMATION
GENERATOR
The MQ Power Model DCA250SSI/DCA250SSIU are 220 kW generators (Figure 3) 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
Emergency Stop Switch
Water Temperature Gauge
Oil Pressure Gauge
Charging Ammeter Gauge
Fuel Level Gauge
Battery Switch
Engine Alarm Lamps
Engine Alarm Lamps
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
Voltmeter
Pilot Lamp
Panel Light/Panel Light Switch
“Control Box” (located behind the Gen. Control Panel)
•Automatic Voltage Regulator
•Current Transformer
•
•Voltage Rectifi er
•Starter Relay
•Engine Control Unit (ECU)
•Voltage
OUTPUT TERMINAL PANEL
The “Output Terminal Panel” is provided with the following:
Three 120/240V output receptacles
Three auxiliary circuit breakers, 50A
Two 120V output receptacles (GFCI), 20A
Two GFCI circuit breakers, 20A
Eight output busbar terminal lugs (3Ø power)
Battery Charger (Optional)
Water Heater (Optional)
OPEN DELTA EXCITATION SYSTEM
These generators are equipped with the state of the art
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 rectifi ed 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 confi guration 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
ENGINE
Each generator is powered by a 6 cylinder, water cooled, direct injection, turbocharged
In keeping with MQ Power’s policy of constantly improving its products, the specifi cations 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.
PAGE 16 — DCA250SSI/DCA250SSIU GENERATOR • OPERATION AND PARTS MANUAL — REV. #0 (01/12/11)