Industrial USB hubs offered by StarTech.com require an external power supply that connects to the terminal block on the hub. StarTech.com does not sell power supplies for these hubs and a power supply must be provisioned separately.
To select a power supply, you need to determine the maximum power requirements (wattage) of the hub.
The equation you should use to determine the power requirements is P = 5 * I * N, where the following is true:
For example, a four-port USB 3.0 hub's maximum power requirement is P = 5 * 0.9 * 4. Therefore, the minimum wattage of the power supply for the four-port USB 3.0 hub is 18 watts.
When you determine the power requirements of the hub, you can choose a power supply. The following criteria must be met when you select the power supply:
Most power supplies come with a rating in volts (V) and amps (A). To determine the current in amps, use I = P / V, where the following is true:
For example, if a hub requires 18 W and you choose a 12 V power supply, the current of the power supply would be I = 18/12, I = 1.5A.
Power supplies are sold by a number of online distributors and resellers. StarTech.com does not provide any official recommendations for distributors or resellers.