It can be used to interface with another machine that has a different voltage to the machine with the relay. For example, you want to give a machine running signal to the other machine, so you energise the relay and use the volt free contacts to tell the other machine that the system is running. Hope this helps.he other reason is that it is cheaper that way since the device doesn't have to have a 24VDC power supply inside it just to provide a signal output. Instead, they rely on you to provide that. This is one of those terms which has come into use as a short hand description for a common configuration.
Five states are in both the eastern and central time zones. Those are Florida, Indiana, Kentucky, Michigan and Tennessee. View the boundary line between eastern and central Time Zones. Five other states are in both the central and mountain time zones. Those are Kansas, Nebraska, North Dakota, South Dakota and Texas. View the boundary line between central and mountain Time Zones.
While not entirely centralized in the grand scheme of things, Central Standard Time is a time zone located six hours behind Universal Coordinated Time (UTC) and is used by both North America and Central America.