Considerations For Sizing A Diesel Generator

A properly-sized diesel generator is essential for having reliable and dependable backup power for your equipment. Improper sizing can easily lead to a variety of issues, including nuisance tripping and eventual generator failure. The following takes a look at various sizing considerations for modern diesel generators.

How Much Power Do You Need?

Diesel generators come in all shapes and forms to handle a broad range of power requirements. The exact type of generator you'll need will depend on a variety of crucial factors:

  • What are your phase requirements? Most homes and small businesses rely on single-phase current at 120 and 240 volts, whereas manufacturing plants and other commercial operations use three-phase current to drive heavy machinery.
  • What type of equipment will the generator power? Lights, refrigerators, HVAC units, chargers and inverters all have unique load requirements that must be considered.
  • What are your startup amperage requirements? Keep in mind that your powered equipment may run at a specific kilowatt rating, but it'll use far more power on startup. For example, a particular piece of equipment may need over 200 kilowatts at startup, despite having an average running load of less than 100 kilowatts.
  • What about future expansion? If you want to add on additional equipment in the future, you'll need to have some sort of reserve set aside to accommodate the addition.

It's not uncommon to find your equipment's power requirements listed in amperes instead of watts. Nevertheless, you can convert the power requirement needed simply by following this simple formula:

  • Wattage = amperes x volts (for resistive loads)
  • Wattage = (amperes x volts) x load factor (for reactive loads)

What are Your Environmental Conditions?

Your diesel generator's overall performance can easily be affected by the environment it's slated to operate within. For instance, high altitudes, high humidity levels and high ambient temperatures can negatively impact generator performance by reducing its power generating capabilities. These effects may be most noticeable in smaller generators with fewer margins for performance loss.

What About Physical Installation?

Several aspects of your diesel generator's physical installation can also play a role in its overall performance. For instance, a poorly-sized generator may exhibit poor cooling performance due to increased workloads, eventually resulting in complete generator failure. Larger units may be deprived of adequate cooling and exhaust air flow due to space constraints and improper blocking in order to reduce generator noise.

If you have any questions, you should consult your certified electrician for more in-depth answers about your power generation needs.