Справочник Пользователя для Mitsubishi Electronics MELSEC -Q/L

6  BASIC INSTRUCTIONS

6.1  Comparison Operation Instructions

Processing details

 • Either of (D), (D)+1 or (D)+2 turns ON depending on the results (small, match, large) after the comparison is made for 

between comparison value (S1), (S1)+1 and the comparison source (S2), (S2)+1.

 • When the contact turns OFF, "(D) to (D)+2" hold the conditions which are immediately before the contact turns ON

OFF.

Operation error

 • In any of the following cases, an operation error occurs, the error flag (SM0) turns ON, and an error code is stored into SD0.

Program example

 • Program that compares the current values of counter C20 with the constant value K100.

• LCPU: The serial number (first five digits) is "16042" or later.
• QnUDVCPU: The serial number (first five digits) is "16043" or later.

(S1):  Head number of devices where comparison data is stored (BIN 32-bit)
(S2):  Data for comparison or the head number of devices where data for comparison is stored (BIN 32-bit)
(D):   Head number of devices where the comparison results are stored (Bit)

J\

U\G

(S1)













(S2)













(D)













4101

The range of 3 points from the device specified in (D) exceeds the range of 
the corresponding device.













Basic

High

performance

Process

Redundant

D

S2

S1

DCMPP

DCMP

D

S2

S1

Command

Command

DCMP

Contact

S1

S2

D

S1

S2

S1

S2

>

=

<

+1

+1

+1

[

[

[

[

[

[

]

]

]

+1

+1

+1

]

]

]

,

,

,

,

,

,

S2

S1

Turns on when

Turns on when

Turns on when

S2

S2

S2

S1

S1

S1

D

D

D +2

+1

Compare K100 with C20.

M0 turns on when K100 > C20 (present value).

M1 turns on when K100 = C20 (present value).

M2 turns on when K100 < C20 (present value).