Product Manual
Table Of Contents
- Table of Contents
- Safety
- General Information
- Specifications
- Unit Serial Number Locations
- Component Locations
- Control Panel
- Power Zone™ Gen Controller
- Controller Features and Functions
- Operator Screens
- Alarm Mute
- Auto/Manual Mode
- Navigation Buttons
- Control Power Switch
- Engine Start
- Engine Stop/Reset
- The Liquid Crystal Display (LCD)
- Operator Screens
- Home Screen
- Engine Screen
- Generator Screen
- Voltage Adjust Screen
- Maintenance Screens
- Generator Summary
- Engine Tab
- Generator Tab
- Alarms Tab
- Input/Output Tab
- Schedule Tab
- Status Tab
- Generator Monitoring
- Engine Monitoring
- Controller Information Displays, Functions and Reset
- Belt Tensioners
- Operation
- Prestart Checklist
- Manual Starting of the Unit
- Auto (Remote) Starting of the Unit
- Derating for Altitude
- Generator Output Connection Lugs
- Fine Voltage Adjustment
- Voltage Selector Switch
- Voltage Regulation
- Customer Convenience Receptacles
- Main Circuit Breaker
- Exhaust Filter Cleaning Operations
- Transfer Switch
- Auto Exercise Timer
- Shutting Down the Unit
- Emergency Stop Switch
- Idle Switch (MMG25I-45I only)
- Towing the Unit
- Lifting the Unit
- Maintenance
- Emissions Information
- Daily Walk Around Inspection
- General Maintenance
- Basic Maintenance Schedule - Isuzu Engine
- Basic Maintenance Schedule - John Deere Engine
- Isuzu Engine Break-In Requirements
- John Deere Engine Break-In Requirements
- Resetting the Maintenance Alarms
- Checking Generator Drive Plate Torque
- Jack Maintenance
- Trailer Wheel Bearings
- Troubleshooting
- Wiring Diagrams
- AC Wiring - MMG25IF4, MMG45IF4
- AC Wiring - MMG35DF4, MMG55DF4
- AC Wiring - 4 Pos. Voltage Selector Switch Option - MMG25IF4, MMG45IF4
- AC Wiring - 4 Pos. Voltage Selector Switch Option - MMG35DF4, MMG55DF4
- AC Wiring Option - Standard Receptacles
- AC Wiring Option - Engine Heater
- AC Wiring Option - Buck Transformer
- AC Wiring Option - PMG
- DC Wiring
- Trailer Lights Wiring
- Wiring Harness - Electric Brake Option
- DC Wiring Option - 12V Battery Charger
- DC Wiring Option - Low Oil Level
- Options & Accessories
Operation
36949 B MMG25I-35D-45I-55DF4 Operating Manual 29
Figure 3-7. Receptacle and Breaker Locations
Power to the receptacles is available any time the generator is running, EVEN IF THE MAIN
CIRCUIT BREAKER IS OFF (O). VERIFY EQUIPMENT CONNECTED TO THE RECEP-
TACLES IS TURNED OFF BEFORE TURNING THE BREAKERS ON. Verify the voltage
selector switch is in the proper position and that the output voltage is correct for the equipment
that is connected to the receptacles. Improper voltage may cause equipment damage or
malfunction.
Note: When the voltage selector switch is in position for 480/277V 3Ø, voltage at the two GFCI receptacles is 139
volts and the voltage at the three twist-lock receptacles is 240/139 volts. Generac Mobile Products does not
recommend using the receptacles in the 480V position. When the voltage selector switch is in position for 208/120V
3Ø, voltage at the three twist-lock receptacles and the two GFCI receptacles is 208/120 volts.
MAIN CIRCUIT BREAKER
The main circuit breaker is located on the main control panel. When the breaker is
OFF (O), power is interrupted between the connection lugs, the optional cam lock
receptacles, and the generator. Once the connections have been made to the
connection lugs or the optional cam lock receptacles, and the unit has been started
and allowed to reach normal operating temperature, the breaker may be switched ON
(I).
The main circuit breaker will be tripped, disconnecting power to the connection lugs
and the optional cam lock receptacles if any of the following items occur while the unit
is running:
Figure 3-8. Main Breaker
50A Circuit
Breakers
20A Circuit
Breakers
120V GFCI
Receptacles
125/250V
Twist-Lock
Receptacles
01034
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