Instruction Execution Timeout; B-2-4 Ensuring Equipment Performance (Takt Time) By Monitoring Instruction Execution Timeout - Omron NX701-1620 User Manual

B-2-4 Ensuring Equipment Performance (Takt Time) by Monitoring

Instruction Execution Timeout

If you do not want to lower the equipment performance (or extend the takt time) when the execution
time of DB Connection Instruction is increased, set a timeout for the instructions.
You can specify a timeout in the TimeOut input variable to the DB_Insert, DB_Update, DB_Select, and
DB_Delete instructions.
For the timeout of instructions, specify the maximum time that can be used for DB access in the takt
time.
If you set a timeout for a DB_Insert instruction for the equipment where production data is stored into
the DB using the DB_Insert instruction at the end of the takt time, for example, a DB Connection
Instruction Execution Timeout will occur for the DB_Insert instruction when the record inserting
processing to the DB is not completed in the takt time. In this case, the record inserting processing to
the DB is executed to the end.
You can continue the operation without lowering the equipment performance (or extending the takt
time) by specifying a timeout for the instruction even if execution time of DB Connection Instructions is
temporarily increased.
 When timeout is not specified
DB_Insert instruction
Takt time Tt
 When timeout is specified
DB_Insert instruction DB_Insert instruction
Timeout
Takt time Tt
Precautions for Correct Use

When a DB Connection Instruction Execution Timeout occurred for a DB_Select instruction,
the values of the retrieved record are not stored in the MapVar in-out variable.

When a DB Connection Instruction Execution Timeout occurs repeatedly, reconsider the task
design and the server environment that contains the DB.
NJ/NX-series Database Connection CPU Units User's Manual (W527)
DB_Insert instruction
Takt time Tt Takt time Tt
DB_Insert instruction DB_Insert instruction
Takt time Tt
The takt time is extended because
execution time of the DB_Insert
instruction is increased.
DB_Insert instruction
The DB_Insert instruction results in a DB
Connection Instruction Execution Timeout.
The record inserting processing to the DB is
executed to the end.
Appendix B
DB_Insert instruction
B-19
B