Coils; Coil Checking - GE PACSystems RX7i Cpu Programmer's Reference Manual

Chapter 4. Ladder Diagram (LD) Programming

4.3 Coils

Coils are used to control the discrete (BOOL) references assigned to them. Conditional logic must be
used to control the flow of power to a coil. Coils cause action directly. They do not pass power flow to
the right. If additional logic in the program should be executed as a result of the coil condition, you
can 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 contact
at 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 Checking

The level of coil checking is set to Show as error by default. If you want a coil conflict to result in a
warning instead of this error, or if you want no warning at all, edit the Controller option: Multiple
Coil Use Warning in the programming software.
The Show as warning option enables you to use any coil reference with multiple Coils, Set Coils, and
Reset Coils, but you will be warned at validation time every time you do so. With both the Show as
warning and the no warning options, a reference can be set ON by either a Set Coil or a normal Coil
and can be set OFF by a Reset Coil or by a normal Coil.
84 PACSystems* RX7i, RX3i and RSTi-EP CPU Programmer's Reference Manual GFK-2950C