initial state command Mitsubishi fx2n plc 2011-01-08 Source: in the actual control system, not only can step instructions for basic instructions and sequence control, and the initial state can command ist (fnc60) with the step instructions for programming, the initial state ist can simplify complex instruction sequence control program. It can automatically set with a variety of operating mode corresponding to the initial state and the related special auxiliary relays. ist command can only be used once and must be placed before the stl circuit.
initial state of the ladder instruction format shown in Figure 10-5. For application instructions refer to forms of expression. Ladder in the source operand [s ?·] represents the first address number, you can take x, y and m,It consists of eight connected
number of soft components. In Figure 10-5, by the composition of the input relay x0 ~ x7. The eight input relay their function as shown in Table 10-2. In which x0 ~ x4 while only one connected, switch must be used to ensure that 5 is not the same as the input on. The destination operand [d1 ?·] and [d2 ?·] can only use the state relay s, the range of s20 ~ s899, which [d1 ?·] represents the work automatically when using the minimum number of relay state , [d2 ?·] represents the work automatically used when the highest state relay number, [d2 ?·] of the address number must be greater than [d1 ?·] of the address number.
ist instruction execution conditions are met, the initial state relay s0 ~ s2 are automatically designated function, s0 is the initial state manual, s1 is the way back to the initial in situ state, s2 is automatically running the initial state. Ist command with special auxiliary relays for eight, its function as shown in Table 10-3. Instruction is automatically set according to ist part of the contents of the special auxiliary relays of the action shown in Figure 10-6, the ladder does not require the user to program, but equivalent to the corresponding special auxiliary relay. m8000 is running to monitor auxiliary relay, when connected to the plc operation.
Table 10-2 Input relay menu
Table 10-3 and ist related special auxiliary relays commands and functions
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