Toshiba PROSEC T3H user manual Expanded Functions

2. Expanded Functions

•Manual mode

In this mode, the manipulation value MV can be directly controlled by the input value of MMV. MV differential limit for manual mode DMMV is effective. MH/ML and DMV are not effective.

When mode is changed from manual to auto or cascade, the operation is started from the current MV.

•Cascade mode

This is a mode for PID cascade connection. PID is executed with CSV as set value.

Different from the auto mode, set value differential limit is not effective. Manipulation value upper/lower limit MH/ML and differential limit DMV are effective.

Bump-less changing from cascade mode to manual mode is available. (Manual mode manipulation

value MMV is over-written by current MV automatically. MMV ← MV)

And, bump-less changing from cascade mode to auto mode is available. (Auto mode set value ASV is over-written by current CSV automatically. ASV ← CSV)

•MV tracking

This function is available in auto and cascade modes. When the tracking designation (A+5 bit 2) is ON, tracking input TMV is directly output as MV.

Manipulation value upper/lower limit MH/ML is effective, but differential limit DMV is not effective. When the tracking designation is changed to OFF, the operation is started from the current MV.

Note

•PID3 instruction is only usable on the main-program.

•PID3 instruction must be used under the constant scan mode. The constant scan interval can be selected in the range of 10 to 200 ms, 10 ms increments.

•The data handled by the PID3 instruction are % units. Therefore, process input value PVC, manipulation value MV, etc., should be converted to % units (scaling), before and/or after the PID3 instruction. For this purpose, the function generator instruction (FUN165 FG) is convenient.

50 PROSEC T3H