Are there any specs on how much current the blue signal wire of a Dell Precision fan connector outputs?

I know that standard fan ports generally supply up to 1A of power (though I have no idea if this is true for Dell, but since I see mine has multiple 0.95A fans with each connected to it's own port I will assume that is true for Dell as well) but what about the blue PWM signal wire? Is there any standard for how much voltage or amps go through that wire? I would assume it's a very low current since it's purpose is just to provide a signal for how fast the fan should go, and other than the fact that Dell uses a proprietary connector/pinout I know that the four wires when you re-pin them just carry the same standard power/signals standard fans use, but I wanted to check if anyone knows how much power goes through this wire. 

Reason being I am making my own connectors and am going to be putting a switch on the blue wire for some additional auxiliary fans so I can control if I want them to just run at full blast or not, but the switch is only rated for 0.5A. I highly doubt it's pushing any even semi-amount of amperage over the signal wire, but I wanted to ask just to make sure before I risk burning something up.