• Answerback checks masking time (MTM) 0 to 10000 seconds.
The default is 4 seconds.
• Bypass command switch (BPSW) Select 0, 1, 3 or 4.
The default is 0.
TIP Even when the serial start is specified, changing the manipulated output value (MV) triggers a transition to the answerback check inhibition (ANCK) status.
SEE
ALSO For more information about the bypass command switch (BPSW), refer to:
“n Bypass Command Switch (BPSW)” on page 1-189
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Initialization Manual
The initialization manual is an error processing function that suspends the control action tem- porarily by changing the block mode to initialization manual (IMAN). This action takes place when the initialization manual condition is established.
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Characteristics of the Initialization Manual
The initialization manual function suspends the control output action temporarily during opera- tion when the initialization manual condition is established, and changes the block mode of the function block to initialization manual (IMAN).
The block returns to the original mode when the initialization manual condition vanishes. How- ever, if try to change block mode in the initialization manual (IMAN) mode, the block only change to that mode when the initialization condition vanishes.
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Initialization Manual Condition
The initialization manual condition is a block mode transition condition that suspends the con- trol action and control output action temporarily by changing the block mode to initialization manual (IMAN).
The initialization manual (IMAN) block mode becomes active only when the initialization man- ual condition is established.
The following example shows when the initialization manual condition establishes or vanish- es:
AUT
↓ Initialization manual condition established IMAN (AUT)
↓ Initialization manual condition vanishes AUT
The initialization manual condition establishes in the following situation:
• When the manipulated output value (MV) connected destination’s data status is commu- nication error (NCOM) or output failure (PTPF).
• When the manipulated output value (MV) connected destination is a switch block (SW-33, SW-91) and the connection is switched off.
• When the manipulated output value (MV) connected destination is a process output mod- ule, and a failure or output open alarm has occurred in the module.
• When the data status of the input signal at the TIN or TSI terminals becomes invalid (BAD) in the tracking (TRK) mode while the output signal is not a pulse-width type.
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MAN Fallback
The MAN fallback is an error processing function that stops the control and forces the function block to enter manual operation state. This action takes place when the MAN fallback condi- tion is established.
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Characteristics of the Man Fallback
The MAN fallback stops the control by changing the function block to manual (MAN) mode regardless of the current operation status, and forces the function block to enter manual oper- ation state.
Once the MAN fallback condition is established, the block mode remains manual (MAN) even when the condition later vanishes.
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MAN Fallback Condition
The MAN fallback condition is used to stop the control by changing the function block to man- ual (MAN) mode regardless of the current operation status, and forces the function block to enter manual operation state. When the MAN fallback condition is established, it indicates that a fatal error has occurred and requests operator interruption.
The following example shows when the MAN fallback condition is established: AUT→MAN
IMAN (CAS) →IMAN (MAN)
The MAN fallback condition is established in the following situation:
• When the answerback abnormality designated on the builder item [Fallback operation on the abnormal answerback] occurs.
• When the manipulated output data status becomes PTPF.
• When the switch connected to INT terminal is turned ON (i.e., the interlock condition is established for changing the block into interlock mode).
• When the data status of the setpoint value (SV) is invalid (BAD).
• When the manipulated output value (MV) is connected to a process I/O and the FCS is having an initial cold start.
• When the manipulated output value (MV) is connected to a process I/O, and one of the I/O points connected to the module has been changed via maintenance.
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Computer Fail
When the computer fail is detected, the function block suspends the action in the remote out- put (ROUT) mode temporarily and switches to the computer backup mode.
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Characteristics of Computer Fail
When the function block mode is remote output (ROUT), the function block receives the ma- nipulated output value (MV) from a supervisory system computer via control bus communica- tion.
When the computer fails, the block changes mode to the preset computer backup mode (MAN, AUT or CAS) which indicates that an abnormality has been detected in the supervisory computer. When the computer recovers, the block returns to the mode before the change. The following section is an action flow of the function block from the time the computer fail condition establishes till it vanishes.
1. When a block mode change command from MAN, AUT or CAS to ROUT is sent while the computer fails (BSW=ON), the function block does not switch to the computer backup mode directly but switches to the transient state mode first.
The transient state mode is a compound block mode consisting of the block mode before the execution of the block mode change command (MAN, AUT, CAS) and a remote mode (ROUT).
2. Then the function block tests the computer condition in the first scan after the block mode change command and switches to the computer backup mode.
The computer backup mode is a compound block mode consisting of the backup mode set via the Function Block Detail Builder (MAN, AUT, CAS) and a remote mode (ROUT). 3. If the computer recovers while the function block is in the computer backup mode, the
block mode changes to remote output (ROUT).
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Computer Fail Condition
The computer fail condition is a block-mode transition condition used to suspend actions in the remote output (ROUT) mode and switches the mode to the computer backup mode. A backup switch (BSW) is provided in function block to define the remote output (ROUT) mode. The status of this switch determines whether the computer has failed or recovered. The value of the backup switch (BSW) can be set from a sequence table or other function blocks.
Switching to a computer backup mode does not take effect if the backup switch (BSW) is on a block mode other than remote output (ROUT).
• When the backup switch BSW=ON, computer has failed • When the backup switch BSW=OFF, computer has recovered
An example when the automatic (AUT) mode has been specified for the computer backup mode is shown as follows:
ROUT
↓ Computer fails
AUT (ROUT)
↓ Computer recovers ROUT
An example when the manual (MAN) mode has been specified for the computer backup mode is shown as follows:
AUT
↓ ROUT command
AUT (ROUT) Transient state mode
↓ After one scan period
MAN (ROUT) Computer backup mode (When BSW=ON)
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Define Computer Backup Mode
Use the Function Block Detail Builder to set the computer backup mode for each function block.
• Computer Backup Mode
Select “MAN,” “AUT” or “CAS” as the mode to be switched to when the computer be- comes down.
The default is “MAN.”
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Block Mode Change Interlock
When the block mode change interlock condition is established, the block mode change inter- lock function stops the control computation processing of the function block running in auto mode, and prohibit the function block changing to automatic operation mode.
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Characteristics of the Block Mode Change Interlock
Stops the control computation processing of the function blocks that are operating automati- cally, and disables the currently stopped function blocks from changing to an automatic opera- tion state. The following actions will take place:
• The block mode changes to manual (MAN).
• Any block mode change command to obtain an automatic operation state (AUT, CAS, or ROUT mode) becomes invalid.
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Block Mode Change Interlock Condition
The block mode change interlock condition is established when the switch at the connected destination of the interlock switch input terminal (INT) is turned ON as a result of continued automatic operation becoming impossible due to an abnormality in the plant, etc.
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Serial Start
▼ Serial Startup Group, MC Block – Serial Startup Interval
The serial start function put the Motor control blocks in the same control station into groups and starts multiple Motor control blocks in the same group sequentially at a specified interval when start requests are issued to these blocks simultaneously.