For a cost effective solution to be used in heave machine automation where magnets cannot be used due to the sheer bulk of ferro-magnetic parts, Reed Switch based ferro-magnetic detection sensors are useful. Ferrous part detection sensors are built by positioning two weak magnets near the seals of reed switches. The two magnets are by themselves not strong enough to transfer the magnetic flux lines between them and close the reed switch. But if this system is brought near a ferrous part, the flux lines travel through the ferrous part and enlarge the two smaller field into one big field which then close the reed switch. As the current carrying capacity is not affected by this sort of construction with multiple magnets, various sizes of reed switches capable of switching different levels of power are available. Ferrous detection sensors can be used in a wide variety of applications in pick and place units, for sensing steel doors of factories and cargo etc.
