> a device is a singular countable mechanism (real or symbolic) which has a specific function. (an electronic device, the infrared device, a literary device) > equipment is non-countable and a general way to refer to a family of objects (some which may be devices, others just objects) that are used in a defined type of activity (sports equipment, diving equipment, filming equipment)

Device = a thing made or adapted for a special purpose. EG a device for measuring pressure, an explosive device Equipment = things needs for a particular purpose. EG office equipment = computers, copiers sports equipment = pads, balls

I used a home made device to open the safe... because the other equipment, we bought at the store, did not work.