Omron CJ - INSTRUCTIONS Reference Manual page 261

Precautions
• Timer numbers are shared with other timer instructions. If two timers share the same timer number,
but are not used simultaneously, a duplication error will be generated when the program is checked,
but the timers will operate normally. Timers which share the same timer number will not operate
properly if they are used simultaneously.
• Timers created with timer numbers 2048 to 4095 will not operate properly when the CPU Unit cycle
time exceeds 100 ms. Use timer numbers 0 to 2047 when the cycle time is longer than 100 ms.
• TIMH(015)/TIMHX(551) timers created with timer numbers 0 to 0255 are refreshed every 10 ms. Use
these timer numbers when the PV is being referenced in the user program.
• The present value of timers programmed with timer numbers 0000 to 2047 will be updated even
when the timer is on standby. The present value of timers programmed with timer numbers 2048 to
4095 will be held when the timer is on standby.
• The Completion Flags for TIMH(015)/TIMHX(551) timers will be updated when the instruction is
executed. (This operation differs from that for CV-series and CVM1 PLCs.)
• Timers will be reset or paused in the following cases. (When a timer is reset, its PV is reset to the SV
and its Completion Flag is turned OFF.)
Condition
Operating mode changed from RUN or MONITOR mode
to PROGRAM mode or vice versa.
*2
Power off and reset
Execution of CNR(545)/CNRX(547), the RESET
TIMER/COUNTER instructions
Operation in interlocked program
section (IL(002)-ILC(003))
Operation in jumped program section
(JMP(004)-JME(005))
*1 If the IOM Hold Bit (A500.12) has been turned ON, the status of timer Completion Flags and PVs will be maintained when
the operating mode is changed.
*2 If the IOM Hold Bit (A500.12) has been turned ON and the status of the IOM Hold Bit itself is protected in the PLC Setup,
the status of timer Completion Flags and PVs will be maintained even when the power is off.
*3 The PV will be set to the SV when TIMH(015)/TIMHX(551) is executed.
• When an operating TIMH(015)/TIMHX(551) timer created with a timer number between 0000 and
2047 is in a jumped program section (JMP(004), CJMP(510), CJPN(511), JME(005)), the timer's PV
will continue timing. (See note.) (The jumped TIMH(015)/TIMHX(551) instruction will not be executed,
but the PV will be refreshed every 10 ms and each cycle after all tasks have been executed.)
Note With the CS1D CPU Units, the PV will not be refreshed in the above case.
• When TIMH(015)/TIMHX(551) is in a program section between IL(002) and ILC(003) and the
program section is interlocked, the PV will be reset to the SV and the Completion Flag will be turned
OFF.
• When a TIMH(015)/TIMHX(551) timer is forced set, its Completion Flag will be turned ON and its PV
will be set to 0000. When a TIMH(015)/TIMHX(551) timer is forced reset, its Completion Flag will be
turned OFF and its PV will be reset to the SV.
• The timer's Completion Flag is refreshed only when TIMH(015)/TIMHX(551) is executed, so a delay
of up to one cycle may be required for the Completion Flag to be turned ON after the timer times out.
• If online editing is used to overwrite a timer instruction, always reset the Completion Flag. The timer
will not operate properly unless the Completion Flag is reset.
• The following restrictions apply if Synchronous Unit Operation is used with a CJ2H-CPU6@-(EIP)
CPU Unit or if the internal pulse control period is set to 1 ms for a CJ2M-CPU@@ CPU Unit with unit
version 2.0 or later.
• An error of up to one cycle time will occur in the timer PV accuracy.
• The timers will not operate correctly if the cycle time exceeds 100 ms.
CS/CJ/NSJ Series Instructions Reference Manual (W474)
0
*1
0
BCD: 9999
*3 Binary: FFFF
Reset to SV.
PV continues
decrementing.
PV Completion Flag
OFF
OFF
OFF
OFF
Retains previous
status.
3. Instructions
3
223