C h a p t e r 5 D e vi c e5 - 1 35_5.2.7 Special Auxiliary Relays (SM)Every special auxiliary relay has its own specific function. Refer to section 2.2.7 in the AS Series ProgrammingManual for more information.5.2.8 Stepping Relays (S)You can easily see the stepping relay in industrial automation to set the procedure. It is the most basic device insequential function chart (SFC) programming. Refer to the ISPSoft User Manual for more information on usingsequential function charts.There are 2048 stepping relays, (S0–S2047). Every stepping relay is like an output relay in that it has an outputcoil, contact A, and contact B. You can use it several times in the program, but the relay cannot directly drivethe external load. You can use the stepping relay as a general auxiliary relay when it is not used in a sequentialfunction chart.5.2.9 Timers (T)• 100 millisecond timer: The timer specified by the instruction TMR takes 100 milliseconds as the timing unit.• 1 millisecond timer: The timer specified by the instruction TMRH takes 1 millisecond as the timing unit.• The accumulative timers are ST0–ST511. If you want to use the device-monitoring function, these timerscan monitor T0–T511.• If you use the same timer repeatedly in a program, including in different instructions TMR and TMRH, thetimer setting value is the one that the timer matches first.• If you use the same timer repeatedly in a program, the timer is OFF when one of the conditional contacts isOFF.• If you use the same timer in a program as the timer for a subroutine’s exclusive use and an accumulativetimer in the program, it is OFF when one of the conditional contacts is OFF.• When the timer is switched from ON to OFF and the conditional contact is ON, the timer is reset andcounts again.• When the instruction TMR is executed, the specified timer coil is ON and the timer begins to count. Whenthe value of the timer matches the timer setting value (value of the timer ≧ setting value), the contact stateis ON.
