Section 3 — Operation

Generac Air-cooled 7 kW, 12 kW and 15 kW Generators

Upon restoration of utility source voltage above a pre- set level, generator circuit board action signals the transfer switch to transfer loads back to that power supply. After retransfer, the engine is signalled to shut down.

The actual sequence of operation is controlled by sensors and timers on a control logic circuit board, as follows:

DANGER

Do not attempt to activate the transfer switch manually until all power voltage supplies to the switch have been positively turned off. Failure to turn off all power voltage supplies may result in extremely hazardous and possibly fatal electrical shock.

A.Utility Voltage Dropout Sensor

•This sensor monitors utility source voltage.

•If utility source voltage drops below about 70 per- cent of the nominal supply voltage, the sensor energizes a 15-second timer.

•Once the timer has expired, the engine will crank and start.

B.Engine Warm-up Time Delay

•This mechanism lets the engine warm up for about 10 seconds before the load is transferred to a standby source.

C.Standby Voltage Sensor

•This sensor monitors generator AC output volt- age. When the voltage has reached 50 percent of the nominal rated voltage, transfer to standby can occur.

D.Utility Voltage Pickup Sensor

•This sensor monitors utility power supply volt- age. When that voltage is restored to above 70 percent of the nominal source voltage, a retrans- fer time delay starts timing.

E.Retransfer Time Delay

•This timer runs for about 15 seconds.

•At end of a 15-second delay, circuit board action de-energizes the transfer relay in the transfer switch.

•Retransfer to utility power source then occurs.

F.Engine Cool-down Timer

•When the load is transferred back to utility power source, the engine cool-down timer starts timing.

•The timer will run for about one minute, and the generator will then shut down.

4.Use the manual transfer handle inside the trans- fer switch to move the main contacts to their “Standby” position, i.e., loads connected to the standby power source (Figure 3.2).

5.To crank and start the engine, set the AUTO/OFF/MANUAL switch to MANUAL.

6.Let the engine stabilize and warm up for a few minutes.

7.Set the generator’s main circuit breaker to its ON (or closed) position. The standby power source now powers the loads.

Figure 3.2 – Manual Transfer Switch Operation

3.5MANUAL TRANSFER OPERATION

‹3.5.1 TRANSFER TO GENERATOR POWER SOURCE

To start the generator and activate the transfer switch manually, proceed as follows:

1.Set the generator’s main circuit breaker to its OFF (or open) position.

2.Set the generator’s AUTO/OFF/MANUAL switch to OFF.

3.Turn OFF the utility power supply to the transfer switch using the means provided (such as a utility main line circuit breaker).

‹3.5.2 TRANSFER BACK TO UTILITY POWER SOURCE

When utility power has been restored, transfer back to that source and shut down the generator. This can be accomplished as follows:

1.Set the generator’s main circuit breaker to its OFF (or open) position.

2.Let the engine run for a minute or two at no-load to stabilize the internal temperatures.

3.Set the generator’s AUTO/OFF/MANUAL switch to its OFF (or open) position. The engine should shut down.

4.Check that utility power supply to the transfer switch is turned OFF.

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Generac 04674-2, 04673-2, 04675-3 owner manual Manual Transfer Operation, ‹ 3.5.2 Transfer Back to Utility Power Source
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04674-2, 04675-3, 04673-2 specifications

Generac, a prominent name in the power equipment sector, offers a range of reliable and efficient energy solutions, including the models Generac 04673-2, 04675-3, and 04674-2. These models are designed to meet diverse consumer needs, from residential applications to larger commercial setups, providing dependable backup power during outages.

The Generac 04673-2 is a standout home standby generator specifically engineered for residential use. It boasts an automatic operation feature, ensuring that power is restored within seconds of an outage. This model operates on a robust Generac engine, delivering a reliable power output that can support essential household appliances and systems, including HVAC units, refrigerators, and sump pumps. One of the main characteristics of this generator is its Quiet Test mode, which runs at a lower RPM to minimize noise while conducting weekly self-tests, ensuring that the system is always ready when needed.

Moving on to the Generac 04675-3, this model offers enhanced features tailored for users needing higher power output. With a larger capacity, it can handle more demanding power needs, making it suitable for larger homes or small businesses. The 04675-3 is equipped with advanced technologies, including the Mobile Link™ remote monitoring system, which enables users to check the status and performance of their generator from anywhere using a smartphone or computer. This connectivity empowers users with real-time information and alerts regarding their generator's operational performance.

The Generac 04674-2 model rounds out the trio, engineered for those who need a powerful standby generator with a slightly different configuration. It features the same robust engine as the other models, ensuring reliability and user-friendly operation. Its standout feature is the integrated transfer switch capability, which allows for seamless transfer of power from the grid to the generator without manual intervention. This model also supports various fuel types, providing flexibility depending on user preference and availability.

All three Generac models focus on safety and efficiency, incorporating features such as excellent ventilation systems, all-weather enclosures, and user-friendly control panels. They are designed for low maintenance, ensuring long-lasting performance without extensive upkeep. With Generac's commitment to innovation and quality, these generators offer peace of mind, enabling users to maintain their lifestyles and operations without interruption during power outages. Whether for home or business use, the Generac 04673-2, 04675-3, and 04674-2 models represent a reliable choice in emergency power solutions.
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