Siemens NAN 67 Series Manual de servicio descargar pdf (Pagina 232)

19-8

Ladder Logic (LAD) for S7-300 and S7-400

C79000-G7076-C504-02

Status Word Bits

I 0.0

If the signal state at input I 0.0 is 1, the SUB_I

box is activated. If the result of the math function

input word IW0 minus input word IW2 is outside

the permissible range for an integer, the OV bit in

the status word is set.

The result of a signal state check with OV is 1.

Output Q 4.0 is set if the check with OV is 1 and

the RLO of network 2 is 1 (that is, if the RLO just

prior to output Q 4.0 is 1).

If the signal state of input I 0.0 is 0 (not

activated), the signal state of both EN and ENO

is 0. If the signal state of EN is 1 (activated) and

the result of the math function is out of range, the

signal state of ENO is 0.

Note: The check with OV is only necessary

because of the different networks. Otherwise, it is

possible to take the ENO output of the math

function, which is 0 if the result is outside the

permissible range.

SUB_I

IN2

OUT

EN ENO

IN2

IW0

IW2 MW10

Network 1:

Network 2:

I 0.1 I 0.2

I 0.2

Q 4.0

BR CC 1 CC 0 OV OS OR STA RLO FC

Write – – – – – x x x 1

Figure 19-8 Exception Bit Overflow

Status Bit Instructions

1 2 ... 227 228 229 230 231 232 233 234 235 236 237 ... 317 318

Sin comentarios

Siemens NAN 67 Series Manual de servicio Pagina 232