Okay, here's a guide for choosing and using a
home diesel generator. Diesel generators, due to their durability, better fuel economy than gasoline engines of the same power, and long run times, have become an essential backup power source for many households, especially in rural areas, villas, or areas prone to prolonged power outages.
A Guide to Purchasing and Using a Home Diesel Generator
1. Power Requirements (The most important of all!)
Calculation: Carefully list all critical appliances you need to operate simultaneously during a power outage, along with their starting power (peak power) and running power (rated power).
Examples of critical appliances include refrigerators, freezers, water pumps (well or booster pumps), home air conditioners (which draw a high starting current!), electric heaters (which consume a lot of power), computers, routers, basic lighting, and medical equipment (if needed).
Important to note:
Starting power is greater than running power: Motor-type equipment (such as air conditioners, refrigerator compressors, and water pumps) draw 3 to 7 times their rated power when starting. The generator must be able to handle this peak power. Reserve margin: Add a 20% to 30% safety margin to the calculated total peak power to determine the generator's rated power. Avoid overloading to extend the life of the equipment.
For example: If you need to simultaneously power a 1.5-horsepower air conditioner (starting power draw approximately 3000W, running power draw approximately 1200W), a refrigerator (starting power draw approximately 1000W, running power draw approximately 200W), several lights (100W), and a router (20W), the peak power demand would be at least 3000W + 1000W + 100W + 20W, which equals 4120W. Choosing a generator with a rated power of at least 5000W (5kW) is a safer option.
2. Brand and Quality:
International brands: Cummins, Perkins, Kohler, Generac (a subsidiary of Techtronic), Deutz - top quality, excellent noise control, advanced technology, and a high price. Top-tier domestic brands include Weichai, Yuchai, Shangchai, Changchai, Quanchai, Kipor, Loncin, and Zongshen. These brands offer high cost-performance, a high market share, a relatively large number of repair service locations, and consistently improved quality.
Choice Recommendation: For home use, the demand for ultimate reliability is less stringent than for industrial use. For budget-constrained users, top-tier domestic brands are the mainstream choice. Be sure to purchase through reputable channels and be careful to identify counterfeits and inferior products.
3. Generator Type:
Open-Frame: Simple structure, low price, and good heat dissipation. The downside is that they are very noisy! They can generally only be used in a separate space away from the home.
Silent/Soundproof: Highly recommended for home use! The generator is housed in a metal enclosure with soundproofing and a muffler. This effectively reduces noise (typically between 65-85 decibels, depending on the model and distance), provides wind and dust protection, and offers a more attractive and safer appearance. Noise control is a key consideration for home use.
Mobile (optional): Typically lower power and equipped with wheels and a push rod for easy mobility. Suitable for small-scale, temporary use, or outdoor activities.
4. Fuel Consumption and Economy:
Diesel engines are most fuel-efficient between 50% and 75% load.
Fuel consumption typically ranges from 200 to 400 grams per kilowatt-hour. For example, a 10kW generator operating at 50% load (5kW) consumes approximately 1 liter per hour (depending on the unit). Calculate your fuel reserves (diesel is safer and more stable than gasoline, but it still requires careful storage).
5. Control System:
Manual Start: The most basic and inexpensive. In the event of a power outage, you must manually pull the generator to the designated position, connect the load, start the machine, and transfer the power source.
Automatic Transfer Switch (ATS): Highly recommended! Used in conjunction with a dedicated automatic transfer switch, the ATS automatically activates the generator and transfers the load to the generator within seconds. Providing truly seamless transfer protection is particularly important for homes with elderly or sick people or those with temperature-controlled equipment (such as fish tanks and incubators). This is key to improving the user experience.
6. Noise Level:
Open-frame models: Can reach 90-110 decibels or even higher, which is very disturbing and unsuitable for use near neighbors.
Quiet models: The noise level is typically calibrated at a distance of 1 meter or 7 meters (e.g., 65 decibels @ 7 meters). Try to choose models with lower noise ratings. The installation location should be away from bedroom windows.
Structure and Key Components Overview
1. Diesel Engine: The core power source. Household diesel engines are typically single- or multi-cylinder, air-cooled, or small, water-cooled. Quality is a key factor in durability and reliability.
2. Alternator: Converts mechanical energy into electrical energy. Key features include voltage stability (AVR - Automatic Voltage Regulator) and waveform purity (sine wave).
3. Control System Panel:
Voltmeter, frequency meter (hertz meter), and ammeter (or indicator light). Output voltage socket (220V AC, 380V sockets may also be available but are rarely used in homes), 12V DC output (for battery charging, etc.).
Start switch (key or button), protection switches (overload, short circuit, low oil pressure, and high water temperature protection).
Automation control module.
4. Fuel system: Fuel tank (internal or external), fuel line, and filter.
5. Cooling system: Air cooling (fan) or water cooling (radiator, water pump).
6. Exhaust system: Muffler. Quiet models have more complex sound-absorbing designs.
Quiet enclosure (quiet models): Steel outer shell, internal sound-absorbing foam, and ventilation and heat dissipation design (very important!).
7. Base and shock absorbers: Support the machine and absorb vibration.
Safety Instructions (Important!!!)
1. Carbon Monoxide Poisoning (Fatal Risk!):
Absolutely do not operate a generator indoors, in a garage (even with the door open), in a hallway, or near doors, windows, or air vents! Exhaust fumes are colorless and odorless, but are extremely dangerous and suffocating.
The generator must be placed outdoors in a well-ventilated, spacious area! Keep away from doors, windows, vents, and neighbors. Wind direction should also be considered. Use a dedicated, extra-long (and properly sized) power cord for the mains connection.
2. Fire Risk:
The generator runs very hot. Keep it away from flammable materials (leaves, paint, fabric, fuel).
When refueling, turn off the engine to cool down! Avoid spilling fuel on hot components. Wipe up any spilled fuel.
Store diesel safely in a dedicated container away from heat sources, flames, and living areas.
Keep the exhaust pipe away from flammable materials.
3. Electric Shock Risk:
The generator must be properly grounded! Operate strictly according to the manual.
Do not "reverse power": Never plug the generator directly into a regular household outlet! This can create a serious electric shock hazard and damage the device. The following must be used:
Manual transfer switch (dual power transfer switch): A mechanical interlock ensures that the mains power and generator are not connected simultaneously.
Automatic transfer switch (ATS): The safest and most convenient option.
Dedicated outlet circuit: Run a separate circuit in the distribution box, connecting only necessary emergency loads, and connect it to the generator through a dedicated outlet. Disconnect this circuit from the mains power.
4. Operational Safety:
Regularly check the oil level and coolant level (for water-cooled models).
Do not touch hot parts (exhaust pipe, cylinder block) during operation.
Keep the machine's surroundings dry and tidy.
Keep children away from a running generator.
Maintenance (to ensure long-term and reliable operation)
1. Daily/pre-startup inspection: Check the engine oil level, coolant level (for water-cooled models), air filter cleanliness, leaks, and ensure that the connecting cables are intact and secure.
2. Regular Replacement:
Engine Oil and Oil Filter: Change after the first 20-50 hours of operation, then every 150-250 hours or annually (even if not in use). Use diesel engine oil that meets the specifications (such as CD, CF-4, CH-4, etc.).
Fuel Filter: Change every 300-500 hours or annually.
Air Filter: Clean or replace regularly (usually every 100-300 hours) depending on the dust level. More frequent changes are required in dusty environments.
3. Cooling System (Water-Cooled): Use antifreeze coolant as required, check the fluid level and concentration regularly, and clean the radiator.
4. Long-Term Storage:
Drain the fuel tank (or fill it up and add diesel stabilizer).
Replace the engine oil (old oil contains acidic substances that can corrode the engine).
Disconnect the negative terminal of the battery to prevent leakage.
Store in a dry, well-ventilated area and protect from dust.
5. Battery Maintenance: Keep the battery fully charged (especially for automatic models), check the electrolyte regularly (for batteries that are not maintenance-free), and clean the electrode terminals.
Purchasing Recommendations
1. Accurately calculate the required power and add a 20-30% safety margin. Don't buy a smaller model for cheap.
2. Prioritize quiet models. Noise is the most detrimental factor in home use.
3. We strongly recommend using an automatic transfer switch (ATS). It's hassle-free, safe, and timely.
4. Choose a reliable domestic brand or an international brand if you have a sufficient budget. Purchase through reputable channels.
5. Carefully read and follow the user manual and safety regulations! Safety first!
6. Plan the installation location: Outdoor, well-ventilated, stable, and rainproof (the silent box comes with built-in rainproofing), away from living areas, convenient for refueling and maintenance, and consider the direction of noise transmission and fuel handling.
7. Consult a professional electrician: For distribution box modifications, ATS installation, grounding, cable specifications, and other matters, always consult a certified electrician to ensure safe and compliant electrical use.
Advantages and Disadvantages
Advantages:
Excellent fuel economy (compared to gasoline engines of the same power), relatively low operating costs.
Diesel is less volatile and slightly safer to store than gasoline.
High torque and strong load capacity for motors.
Rugged engine construction and long design life; with proper maintenance, it can operate for tens of thousands of hours.
Suitable for extended periods of continuous operation (e.g., power outages exceeding 8 hours).
Disadvantages:
High initial purchase cost (for the generator itself and the ATS).
Noise and vibration are loud (even silent generators are louder than gasoline engines).
Cold start performance is inferior to gasoline engines (caution for use in extremely cold regions).
Generally larger and heavier than gasoline engines of the same power.
Odor and black smoke are present during operation (may be noticeable during startup or heavy loads).
Requires more professional maintenance (compared to gasoline engines).
Final Reminder:
A home diesel generator is a significant emergency equipment investment. Before purchasing, be sure to do your research and carefully assess your needs, budget, installation conditions, and safety risks. Safety is always paramount! Proper installation, proper use, and regular maintenance are key factors in ensuring it can reliably and safely provide power to your home when it matters most. If your area experiences only occasional power outages, a small gasoline generator or a large-capacity outdoor power source may also meet your needs, offering lower costs, greater portability, and quieter operation. Choose the best option for your situation.
