Omron CJ - INSTRUCTIONS REFERENCE MANUAL 07-2009 Reference Manual page 251

3. Instructions
Function
• When the timer input is OFF, the timer
specified by N is reset, i.e., the timer's PV is
reset to the SV and its Completion Flag is
turned OFF.
• When the timer input goes from OFF to ON,
TIM/TIMX(550) starts decrementing the PV.
The PV will continue timing down as long as
the timer input remains ON and the timer's
Completion Flag will be turned ON when
the PV reaches 0.
• The status
Completion Flag will be maintained after the
timer times out. To restart the timer, the
timer input must be turned OFF and then
ON again or the timer's PV must be
changed to a non-zero value (by MOV(021),
for example).
• The setting range for the set value (SV) is 0
to 999.9 s for TIM and 0 to 6,553.5 s for
TIMX(550).
• The timer accuracy is -0.01 to 0 s.
Note The timer accuracy for CS1D CPU Units is
10 ms + the cycle time. The timer accuracy
for unit version 4.1 of the CJ1-H-R is -0.1 to
0 s.
Hint
A TIM/TIMX(550) instruction's PV and Completion Flag can be refreshed in the following ways
depending on the timer number that is used.
Timers Created with Timer Numbers 0000 to 2047
Execution of
TIM/TIMX(550)
After execution of all cyclic
tasks
80-ms interval refreshing
• Timers are reset (PV = SV, Completion Flag
OFF) by power interruptions unless the IOM
Hold Bit (A500.12) is ON and the bit is
protected in the PLC Setup. It is also
possible use a clock pulse bit and a counter
instruction to program a timer that will retain
its PV in the event of a power interruption,
as shown in the following diagram.
• When the timer set value is #0000, timeup
occurs when the instruction is executed.
214
of the timer's PV and
• The PV is updated every
time that TIM/TIMX(550)
is executed.
• The Completion Flag is
turned ON if the PV is 0.
The Completion Flag is
turned OFF if the PV is
not 0.
The PV is also updated
every cycle after executing
all cyclic tasks.
If the cycle time exceeds
80 ms, the timer's PV is
updated every 80 ms.
Timer input
SV
Timer PV
Completion
Flag
The following timing chart shows the behavior
of the timer's PV and Completion Flag when
the timer input is turned OFF before the timer
times out.
Timer input
SV
Timer PV
Completion
Flag
Timers Created with Timer Numbers 2048 to 4095
Execution of TIM
Execution 1-s clock
pulse bit
condition
CS/CJ/NSJ Series Instructions Reference Manual (W474)
• The PV is updated every
time that TIM is exe-
cuted.
• The Completion Flag is
turned ON if the PV is 0.
The Completion Flag is
turned OFF if the PV is
not 0.
Count input
Reset input