The D2, D3, and S-Type series have identical power usage figures for all MVP models: Heater Blower (HB), Tornado (TR), and Ring of Fire (RF). The COOLDOME™ (CD) series also has identical power usage for the D2 and S-Type models, however the D3 COOLDOME™ (CD) uses a dual cooler which doubles the peak power consumption over the other COOLDOME™ (CD) models. Dotworkz has tested the majority of models using a special 25 watt resistor for camera load simulation. Most cameras will create a lower overall power use from model-to-model. Please read test conditions on each model, as some will allow for added camera power load. These are for exact power usages, but when designing a system please use transformers or power supplies with a 30-50% higher maximum power rating (VA or wattage) in order to create a robust and reliable power system.