When you purchase a high-intensity discharge (HID), also known as High Pressure Sodium (HPS) lighting system, the assumption is that you’re going to be drawing the exact wattage at the wall, that the system references. For example, a 600w HPS will use 600 watts of electricity, a 315w CMH will use 315 watts. NOT TRUE.
That number being used, refers to the bulb’s draw, not the system’s.
So how much more?
We’re talking about 10%! on a good quality digital balast and much more on a magnetic. We’ve provided three examples below: for digital 600w HPS, 600w 400V HPS and 315w CMH.
As you can see from the photo, a traditional 600w HPS light on a digital ballast, will use 667+ watts of your electricity.
As you can see from the photo, a 600w, 400V HPS light will use 635+ watts of your electricity.
As you can see from the photo, a traditional 315w Ceramic Metal Halide light will use 339+ watts of your electricity.
Conclusion; Always check you wattage with a power meter, you can find them for sale in our tools section here https://diyleduk.com/collections/grow-room-tools/products/plug-in-power-meter