When selecting a generator for your home, RV, or job site, it’s crucial to understand the difference between starting watts and running watts. These two power ratings are essential in ensuring that your generator can handle the electrical demands of your appliances and tools. In this article, we’ll delve into what starting watts and running watts mean, why they matter, and how to choose the right generator based on these ratings.
What Are Starting Watts?
Starting watts, also known as surge watts or peak watts, refer to the extra power required to start an electrical device with a motor. Many appliances, such as refrigerators, air conditioners, and power tools, need a burst of energy to overcome inertia and get the motor running. This initial surge is typically much higher than the power needed to keep the appliance operating continuously.
For example, a refrigerator might require 2000 starting watts to kick-start its compressor but only 700 running watts to keep it operating. This spike in power demand usually lasts just a few seconds but is critical for the proper functioning of the appliance.
What Are Running Watts?
Running watts, sometimes called rated watts or continuous watts, are the amount of power an electrical device needs to operate under normal conditions. Once the initial surge (starting watts) has passed, the device will continue to run at this lower, steady power level.
Using the previous example, after the refrigerator’s compressor starts up using 2000 starting watts, it will then run continuously at 700 running watts. This rating indicates the ongoing power consumption and is vital for calculating the total load your generator must support over extended periods.
Why Both Ratings Matter
Understanding both starting and running watts is crucial for several reasons:
Preventing Overload: Generators have maximum wattage limits. If you exceed these limits, you risk damaging the generator and connected devices. Knowing the starting and running watts helps ensure you don’t overload your generator.
Proper Sizing: To choose the right generator, you need to sum up the running watts of all the devices you plan to power simultaneously. Additionally, account for the highest starting watts among those devices to ensure your generator can handle the initial power surge.
Efficiency and Longevity: Operating a generator within its capacity ensures efficient performance and extends its lifespan. Consistently running a generator at or near its maximum capacity can lead to wear and tear, reducing its operational life.
How to Calculate Your Power Needs
To determine the appropriate generator size, follow these steps:
List Your Devices: Make a list of all the electrical devices you intend to power with the generator.
Find Wattage Ratings: Check the user manuals or labels on each device to find their running watts and starting watts. If the starting watts aren’t listed, a general rule of thumb is to multiply the running watts by three for devices with motors.
Total Running Watts: Add up the running watts of all the devices you plan to use simultaneously.
Highest Starting Watts: Identify the device with the highest starting watts and add this number to your total running watts.
For instance, if you have a refrigerator (700 running watts, 2000 starting watts), a TV (150 running watts), and a microwave (1000 running watts, 1200 starting watts), your calculations would look like this:
Total running watts: 700 + 150 + 1000 = 1850 running watts
Highest starting watts: 2000 starting watts (refrigerator)
Therefore, you’ll need a generator that can handle at least 1850 running watts and 2000 starting watts.
Choosing the right generator involves more than just picking one that fits your budget; it’s about understanding the power requirements of your devices. By knowing the difference between starting watts and running watts, you can make an informed decision that ensures your generator operates efficiently and reliably. Always consider both ratings to avoid overloading your generator and to provide stable, continuous power to your essential appliances and tools.
