Omron NB3Q-TW_B Startup Manual page 118

7
The communications of the PT and PLC are normal, but why are some numeric values are
indicated as "****"
When the data coming from registers communicating with the PLC exceeds the setting range of
the Number Display or Number Input, "****" will appear. It indicates an overflow of a numeric
value. The user can set the integer bit digit number range of the Number Display or Number
Input larger through the software to make numeric value display normal. For example, change
the integer bit digit number from 3 to 4.
8
Why is the window-switching speed of the PT becoming slow after macro instructions are used
When writing macro-code programs, if a large of number of address variables of the PLC or
slave Unit are defined, the execution speed of the PT may suffer. When executing a macro
program, the processor picks up the variable addresses defined first, executes macro
operation, then carries out output. If the macro program is executed at a high frequency, a large
amount of time is used to perform communication with the slave Unit, thus affecting the
execution speed of the PT as a whole.
NB-series Programmable Terminals Startup Guide Manual(V109)
6 Maintenance and Troubleshooting
6
6-29