Automationdirect.com DL05, Руководство пользователя

Страница: 338 / 480

RLL
PLUS
Stage Programming
7–20
RLL
PLUS
Stage Programming
Recall the last convergence stage only
has power flow when all CV stages in the
group are active. To complement the
convergence stage, we need a new jump
instruction. The Convergence Jump
(CVJMP) shown to the right will transition
to Stage S5 when X3 is active (as one
might expect), but it also
automatically
resets all convergence stages in the
group
. This makes the CVJMP jump a
very powerful instruction. Note that this
instruction may only be used with
convergence stages.
CVJMP
S5
X3
CV
S2
CV
S4
Convergence
Jump
SG
S5
The following summarizes the requirements in the use of convergence stages,
including some tips for their effective application:
S
A convergence stage is to be used as the last stage of a process which
is running in parallel to another process or processes. A transition to the
convergence stage means that a particular process is through, and
represents a waiting point until all other parallel processes also finish.
S
The maximum number of convergence stages which make up one
group is 16. In other words, a maximum of 16 stages can converge into
one stage.
S
Convergence stages of the same group must be placed together in the
program, connected on the power rail without any other logic in
between.
S
Within a convergence group, the stages may occur in any order, top to
bottom. It does not matter which stage is last in the group, because all
convergence stages have to be active before the last stage has power
flow.
S
The last convergence stage of a group may have ladder logic within the
stage. However, this logic will not execute until all convergence stages
of the group are active.
S
The convergence jump (CVJMP) is the intended method to be used to
transition from the convergence group of stages to the next stage. The
CVJMP resets all convergence stages of the group, and energizes the
stage named in the jump.
S
The CVJMP instruction must only be used in a convergence stage, as it
is invalid in regular or initial stages.
S
Convergence Stages or CVJMP instructions may not be used in
subroutines or interrupt routines.
Convergence Jump
(CVJMP)
Convergence
Stage Guidelines