Mitsubishi Electric Q06CCPU-V, Руководство пользователя

Страница: 228 / 618

6
- 10 6.2 Fail-Safe Circuit
6
PREPARATORY PROCEDURES AND SETTING
(3) Fail-safe measures against C Controller system failure
The C Controller module can detect its own failure by the self-diagnostic function.
However, it may not be able to detect a failure that occurred in an I/O control part.
In such a case, all of inputs and outputs may turn on or off depending on the failure,
and normal operation of the control target and safety may not be ensured.
Though Mitsubishi products are manufactured under strict quality control, it is
recommended to configure external fail-safe circuits so that a C Controller system
failure will not result in mechanical damage or accidents.
The following shows a system example and a fail-safe circuit example.
* 1 The output module for fail-safe must be installed to the last slot of the system. (Y80 to Y8F in the
above system)
* 2 Create a program so that Y80 alternates between ON and OFF at intervals of 0.5 seconds. (Use
the QBF_Y_Out_BitEx function to set Y80 to on/off.)
* 3 Since Y80 turns on and off at 0.5s intervals, use a non-contact output module (a transistor in the
above example).
Figure 6.5 System example
Figure 6.6 Fail-safe circuit example
Extension cable
Y80 to
Y8F
Points per
slot
Output module for fail-safe *
1
16 16 16 16 16
Points per
slot
16 16 16 16
Input
Output
Output
Empty
Output Output
Output
Input Input Inout
Load
Load
User program
*2
ON delay timer
1s
OFF delay timer
1s
T2 T1
24VDC
Y80
Y81
Y8F
24V
0V
Y80
0.5s 0.5s
C Controller module Output module
*3
MC
T1
T2
MC