Chapter 4. Ladder Diagram (LD) Programming84 PACSystems* RX7i, RX3i and RSTi-EP CPU Programmer's Reference Manual GFK-2950C4.3 CoilsCoils are used to control the discrete (BOOL) references assigned to them. Conditional logic must beused to control the flow of power to a coil. Coils cause action directly. They do not pass power flow tothe right. If additional logic in the program should be executed as a result of the coil condition, youcan use an internal reference for the coil or a continuation coil/contact combination.A continuation coil does not use an internal reference. It must be followed by a continuation contactat the beginning of any rung following the continuation coil.Coils are always located at the rightmost position of a line of logic.4.3.1 Coil CheckingThe level of coil checking is set to Show as error by default. If you want a coil conflict to result in awarning instead of this error, or if you want no warning at all, edit the Controller option: MultipleCoil Use Warning in the programming software.The Show as warning option enables you to use any coil reference with multiple Coils, Set Coils, andReset Coils, but you will be warned at validation time every time you do so. With both the Show aswarning and the no warning options, a reference can be set ON by either a Set Coil or a normal Coiland can be set OFF by a Reset Coil or by a normal Coil.
