How can i drive a 5v 120VAC 80mA with 15A contacts with a raspberry pi?
One solution (of many) is to use the Raspberry Pi GPIO pin to drive a logic-level MOSFET.







simulate this circuit &ndash; Schematic created using CircuitLab

The GPIO only needs to sink/source enough current to turn the MOSFET on and off. The 10k resistor is there to keep the MOSFET in a defined state if the GPIO goes high-impedance. The diode across the coil clamps the reverse EMF generated when the coil is switched off, protecting the rest of the circuitry.

(It is up to you to choose an appropriate MOSFET and diode; the examples shown are for illustration only.)