ALTUS Nexto Series User Manual

6. REDUNDANCY WITH NX3030 CPU
Configuration Description Default Options
Memory (%M)
Redundancy %M Memory
Offset
Redundant %M memory ini-
tial address
0 0 (disabled)
Redundancy %M Memory
Length
Redundant %M memory
size
0 0 to 65536
Memory (%I)
Redundancy %I Memory
Offset
Redundant %I memory ini-
tial address
0 0 (disabled)
Redundancy %I Memory
Length
Redundant %I memory size 16384 0 to 81920
Memory (%Q)
Redundancy %Q Memory
Offset Reserved For I/O
Drivers
%Q redundant memory off-
set reserved for I/O drivers
initial address
0 0 (disabled)
Redundancy %Q Memory
Length Reserved For I/O
Drivers
%Q redundant memory off-
set reserved for I/O drivers
size
16384 0 to 81920
Redundancy %Q Memory
Offset Reserved For Diag-
nostics
%Q redundant memory off-
set reserved for diagnostics
initial address
65536 0 to 81919
Redundancy %Q Memory
Length Reserved For Di-
agnostics
%Q redundant memory off-
set reserved for diagnostics
size
16384 0 to 81920
Table 206: NX4010 parameters
6.4.7. I/O Drivers Configuration
The configuration of I/O drivers, at first, isn’t different in relation to a non-redundant CPU.
What can be observed is that some I/O drivers have commands which allow its use in a redundant CPU, but it doesn’t imply
in configuration differences. These commands, normally, must be executed in the NonSkippedPrg program. E.g. a MODBUS
RTU master driver in a RS-485 serial network must be disabled in a non-Active CPU using the code inserted by the user in
NonSkippedPrg. More information regarding administration of MODBUS driver in a redundant system can be found in the
MODBUS Instances Managing in Redundant System section.
In the case of PROFIBUS network, there are also special different commands for the CPUs in Active and Non-Active states.
In this case, however, the redundancy management executes such commands automatically, without any user management.
To configure PROFIBUS I/O remotes, including remotes and I/O modules, see NX5001 Modules Configuration section
from this manual.
6.4.8. MainTask Configuration
The configuration screen associated to the only task of a redundant CPU, called MainTask, which is cyclic, can be accessed
through a click on the MainTask in the Device Tree.
Two parameters must be adjusted on this screen:
MainTask Interval
Watchdog Time
Furthermore, the screen shows an estimative of the necessary time to manage the redundancy, calculated by MasterTool.
Such estimative is only reliable after the project is complete, with all POUs developed and redundant memory areas defined.
Several considerations must be taken in order to adjust correctly the MainTask cycle time:
The interval time must be sufficiently low to allow the proper process control, taken in account all control feedback times
The interval time must be high enough for allowing, at least, the sum of the following times:
• The NonSkippedPrg and ActivePrg POUs maximum execution time, together
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ALTUS Nexto Series Specifications

General

Brand	ALTUS
Model	Nexto Series
Category	Computer Hardware
Language	English