To continue the detailed information in the first installment on the generators, we will talk about other important technical aspects of this equipment. These aspects can serve as guidance or as basic information in case it is required to acquire one of these pieces of equipment.
Types of generators or generator sets
Different types of electric generators.
Currently there is a wide variety of generators, which can be classified according to the fuel they use, the voltage they generate or the type of equipment start-up.
Depending on the type of fuel:
- Diesel (Diesel equipment): They are ideal for power requirements of more than 5 kW and for intensive or continuous use. They are perfect for jobs in workshops and remote sites where the power of various electrical machines is required, including MIG and TIG welding equipment, which require tolerance to large currents.
- Naphtha: They are the most economical generator sets. They are used for powers less than or equal to 2 kW if they are used frequently and for powers of up to 5 kW if they are used sporadically. They are perfect for small businesses where it is only necessary to cover the energization of up to two refrigerators, cash registers and energy-saving lamps for short periods of time. They are also suitable for keeping in the garage, for small workshops and for building contractors who do not require the power of many machines at the same time (for example a paint mixer, a spinning top concrete mixer etc.
- Gas: These generators are of small or medium power —up to 5 kW— and ideal for frequent use. Its use is indicated for small businesses with a refrigerator or freezer located in regions where power outages are frequent and for contractors with small energy requirements (as we saw in the previous point with gasoline generators).
Classification based on the type of generator voltage:
- Monophasic: In general, household gasoline or gas generators or generator sets deliver alternating current at a maximum voltage of 220 V and a frequency of 50 Hz (with a direct current terminal for 12 V). This is a general rule for all those gas or gasoline generators that deliver a maximum power of 5 kW.
- Triphasic: Diesel cycle generators (or generator sets) with a power output greater than 5 kW usually incorporate outlets for alternating current of 380V and 50 Hz; of course they also offer 220V outlets.
Classification according to the type of generator start:
- Manual start without load switch: This is the cheapest starting system but also the least practical. Extension cables must be arranged and various loads connected to them, to obtain the capacity of the generator. Of course, one person must be in charge of connecting and starting the equipment. This type of start-up is indicated for generators of up to 5 or 6 kW, preferably those that work with gasoline or gas.
- Manual start with load switch: in this case the switch handles all the load current and is independent of the generator capacity. When the generator set is in operation, some loads must be disconnected to avoid exceeding its capacity. Like the previous type of starter, this is recommended for generators up to 5 or 6 kW, gasoline or gas.
- Electric start with manual load switch: with this type of start, the start button must be pressed and once the generator is running, the switch must be placed in “generator” mode. This type of starting is ideal for generators with power greater than 6 kW.
- Electric start with automatic control: this type of start-up is used for lower power generators and provides protection to them, since the possibility of overloading the generator is avoided, by automatically disconnecting the devices with the highest consumption, in the event that an alteration in power is detected.
Installation Instructions
Location and suitability of the space for the generator set
Example of a good location for a large generator. Although it is a museum piece, the roof and foundations prepared for this purpose give us an idea of ​​how a large diesel or gasoline-type generator set should be installed.
The area destined for the installation of the generator set must meet certain requirements to allow the perfect operation and maintenance of the equipment.
The installation space must be soundproof and it must have an outlet to the outside for the gases; it should also be provided with good ventilation to allow fresh air to enter. This will prevent the equipment’s engine from deteriorating by not getting the optimum gas mixture in the cylinders and will eliminate the risk of poisoning and death from carbon monoxide emissions.
It is vitally important that the space where the generator is installed is not closed. It is not enough to have an opening; exhaust fumes could build up and cause poisoning and even death if care is not taken. To do this, they must be installed in rooms where the air circulates freely, both to enter and to escape. The best solution is a shed with a gabled roof, with a solid wall up to one meter high and then an open metal mesh enclosure that allows full air circulation.
Location not recommended: there are no openings for the exhaust of combustion gases except for the pipes installed on the ceiling, which are insufficient. The board on the right is located a few centimeters from where the equipment would be, so it would be inaccessible or uncomfortable and in case of emergencies it could not be operated. Finally, the ceramic coating of the walls would create reverberations and echoes, enhancing the noise.
It is also important that the room intended to house the generator have thermal insulation to protect equipment from weather fluctuations.
The electrical output of the generator must be carried out through the magneto-thermal and differential protection system; under no circumstances should it be connected directly to the electrical installation.
Maintenance and commissioning
Before starting up a generator set, several aspects must be taken into consideration regarding its operation.
If the generator works on diesel fuel and is for frequent use, a tank similar to the one used by the equipment and a reserve tank must be installed near the generator. Please note that these tanks must be accessible to refuel.
When starting up the generator, you must consider that for the equipment to be ready to assume the load, you must wait around 10 seconds, if the equipment has a preheating system. Otherwise, the waiting time is between 5 to 10 minutes.
Once the generator is started for the first time, its maintenance must be taken into account for better performance.
Engine lubricating oil should be changed periodically after a certain number of operating hours. In engines that work with diesel, the spark plugs must also be changed. Likewise, the air and fuel filter must be cleaned. To find out how often, it is best to refer to the manufacturer’s information.
If the generator is left idle for a long time, it is recommended to start it every month or two. Another important recommendation is to empty the fuel tank when the generator is not working, in the event that gasoline and oil are used, and use a new mixture before starting the generator.
Remember to read the manufacturer’s instructions and user manual before starting to use the generator or generator set.
