Validation Of Interruptions; Performances - ABB AC 31 Technical Manual

2.2. Validation of interruptions

2.3. Performances

Alarm (hardware interruption)
Cyclic interruption
Max length
Page 6-8
Program Optimization
The interruptions may, or may not, be validated (activated) depending on the process.
Once an interruption has been defined the name is automatically placed in the function block
list as a function block
An interruption is validated through the utilization of the function block.
Taking the previous example; the interruptions INT1, INT2 and INT3 are validated in the
following manner in the program:
The delay, for considering the interruption, depends on the central unit configuration.
In fact, when the central unit is configured as master the CS 31 bus management has the
highest priority.
AC 31 master central unit
max. time. 2,5 ms
min. time. 5 ms
1,5 ms
It is recommended that the DI and DO functions are used when immediate access to physical
inputs/outputs becomes necessary, in an interruption, for immediate information execution
(attention, these functions can only be used for the inputs/outputs of the central unit and its
extensions).
Example: the physical command of an output may be carried out independently of the central
unit cycle time.
The unit cannot effectuate more than one task at a time.
Certain tasks have a higher priority than others.
The descending priority is:
- Communication with a unit on the CS 31 bus
- Interruption on the I62.02 input
- Interruption on the I62.03 input
- Cyclic interruption
VALID1
EN
VALID2
EN
VALID3
EN
AC 31 slave central unit
max. time 2,5 ms
min. time 1 ms
3 ms
INT1
INT2
INT3
stand-alone central unit
max. time 250 µs
min. time 1 ms
3 ms
ABB Control - AC 31
1SBC 260400 R1001-b 06.99