The multi-sequence monitor controls the execution of a sequence generator by selecting the order of step execution in a process. It operates like the sequence monitor (function code 124), but has enhanced functionality. The multi-sequence monitor block provides multi-batch recipe control, halts sequences and inserts steps. Each multi-sequence monitor block controls the execution of eight phases. A phase is a step that may vary from recipe to recipe. This block provides a means to change the order that predefined steps execute in different recipes. The phases always execute in numerical order from one to eight. Four parameters (step type, normal step number, fault step number, and recipe value) define each phase. The multi-sequence monitor block performs a logical action based on the value of a control status input from a device monitor block, and a boolean step trigger input. Depending on the value of the control status input, the next step can be either a fault step or one determined by internal logic. The multi-sequence monitor block can be placed in either automatic or semi-automatic mode, and includes hold/resume, executed stop (E-STOP), insert step and insert phase inputs. Each multi-sequence monitor block handles up to eight phases. If more than eight phases are required, multi-sequence monitor blocks can be linked together in series fashion with S1.
1. Maximum values are:9,998 for the BRC-100, IMMFP11/12 and 31,998 for the HAC
Each multi-sequence monitor block executes eight phases in numerical order. The step number executed in each phase comes from a different function block. The step type, fault phase, and recipe value for each phase also come from other function blocks. Since all the values are specified external to the multi-sequence monitor block, this arrangement enables the operator to vary those values either manually or through logic (for example, recipe table blocks). Thus, the multisequence monitor block can control the execution of many different sequences, allowing the operator to control several consecutive sequences with one block. Figure 134-1 shows a common configuration using a multi-sequence monitor block
to control several sequences using recipe table blocks.
The multi-sequence monitor block uses the values of two inputs to determine the next step number in a batch process. The first is the control status input, which defines the current state of the devices controlled by the multi-sequence monitor block. This input can be 0.0 (good), 1.0 (bad), or 2.0 (waiting). This value determines whether the next step will be a normal step or a fault step. When the control status input is 1.0 (bad), a fault step initiates unless control is overridden.
The second input is the step trigger. The step trigger is dependent on the current step and the results of auxiliary logic associated with the device in question. Each step of a batch sequence often requires auxiliary logic to perform functions in addition to controlling the device (i.e., change controller set points, totalize flows, etc.). This auxiliary logic ties into the batch execution configuration. Execution of the auxiliary logic associated with the current step number initiates when the current step number is read from the sequence generator block. The current step number also selects from the results of that auxiliary logic the boolean signal output to the multi-sequence monitor block as the step trigger.
The values of the step trigger and the control status input are then tested against the step type to determine whether the next step can be executed. The step type defines the values of the step trigger and the control status that must exist for the sequence to proceed to the next step. The step type also defines whether semi-automatic control is permitted (operator intervention).
To initiate the multi-sequence monitor operation, configure the resume phase (S9) as some number other than zero, and place the sequence in hold first and run later.
The multi-sequence monitor block can operate in automatic or semi-automatic mode. In the automatic mode, the sequence is dependent on the values of the control status input and the step trigger. In the semi-automatic mode, the sequence is dependent on the values of the control status input, the step trigger, and the semi-automatic step trigger. The operator must (as one of the conditions to proceed to the next step) activate the semi-automatic step trigger manually to proceed with the sequence. The block can be placed in semi-automatic mode only if both the semi-automatic permissive and step type specifications are configured to permit it.
Execution of a phase in a multi-sequence monitor block can be halted when the step type and hold/resume specifications permit. When a phase halts, a step can be inserted into the phase sequence. On a zero to one transition of the insert trigger, the insert step number and the insert recipe value are output with a jump step trigger. The insert step done specification toggles from a zero to one when the insert trigger goes to zero and the step trigger makes a zero to one transition. If the hold/resume specification goes to zero (resume) during an insert step, the sequence remains in hold until
the insert step is complete. When the insert step is complete, the insert step done output goes from zero to one and the sequence resumes at the resume phase number.
The E-STOP specification drives the sequence generator block and multi-sequence monitor block to the reset step when it is one. This is normally a remote control memory block set up as an E-STOP.
S1 - NXT
Block address of next multi-sequence monitor block in the series of blocks used to execute the sequence. If this value equals zero there are no more blocks in the sequence. Each multi-sequence monitor block can accommodate eight phases. If the sequence contains more than eight steps, blocks can be linked in a series with the last phase of the first block initializing the first phase of the second block, etc. Therefore, phases one through eight in the second multi-sequence monitor block are phases nine through 16 in the sequence.
S2 - CSI
Block address of control status input. The value in this block represents the control status of the devices used in the control loop. The output of this block is good when all inputs are good, bad when any one input is bad, and waiting if any one input is waiting for a reply from a device driver or device monitor block. This value and the value of the step trigger select the next step in the sequence. When the control status input is bad, the fault step is automatically output. If the control status input is good or waiting, output depends on the step type for the current phase.
0.0 = good
1.0 = bad
2.0 = waiting
S3 - STEP
Block address of the step trigger. The value in this block, with the control status input, selects the next step in the control sequence. The step trigger generates by auxiliary logic used for the batch process. The step trigger input can either be one or zero. The state acted on depends on the step type for the current step.
S4 - E-STOP
Block address of E-STOP input. The E-STOP specification drives the block to step zero (the reset step) whenever it has a value of one. The block referenced by this specification is normally a remote control memory block set up as an E-STOP.
S5 - HOLD
Block address of hold/resume input. The multi-sequence monitor block can hold the sequence at certain steps. The hold/resume function is active only when the step type is configured to permit it (tens digit is zero). This specification enables the holding of the sequence or insertion of a step into the sequence. If the sequence holds at a step and the insert trigger makes a zero to one transition, then a step will be inserted into the sequence. Otherwise, the sequence holds until the hold/resume input makes a one to zero transition. The block then resumes operation at the phase specified with S9, the resume phase number.
0 = no hold
1 = hold the sequence at the current step
1 to 0 transition = resume operation at the phase specified by <S9>
S6 - PERM
Block address of the semi-automatic permissive. When the value in this block is zero, the semi-automatic mode is permitted unless <S9> overrules it.
0 = both automatic and manual modes permitted
1 = only automatic mode permitted
S7 - SEMI
Block address of the semi-automatic trigger. When the semi-auto mode is permitted by step type and the semi-auto permissive <S6> is zero, the operator must change this value from zero to one to initiate the next step of the sequence.
S8 - INTRG
Block address of insert trigger. The value in this block initiates the insertion of a step into a sequence. If the hold/resume input <S5> is at hold and this input makes a zero to one transition, the insert step number <S10> and insert recipe value <S11> will be output from the block. This function is applicable only when the hold/resume input is permitted.
S9 - RES
Block address of resume phase number. When the hold/resume input makes a one to zero transition, the block resumes operation at the phase specified here.
S10 - INSTP
Block address of insert step number. The step identified here will be inserted in the sequence on a zero to one transition of the insert trigger <S8>, when the hold/resume input <S5> is at hold.
S11 - INRCP
Block address of insert recipe value. The recipe value identified here is inserted in the sequence on a zero to one transition of the insert trigger <S8>, when the hold/resume input <S5> is at hold.
S13 - TYPE1
(Block address of the step type for Step 1) Each step type is made up of two digits. The ones digit defines the state of the control status input and step trigger necessary for the block to initiate the next step of the sequence. The tens digit identifies the control options available for the step.
S14 to S20 - TYPE2 to TYPE8
Block addresses of the step types for steps two through eight. Refer to S13 - TYPE1 for definitions.
S21 to S28 - STEP1 to STEP8
Block addresses of the phase n normal steps. These specifications identify the block containing the number of the step the system should execute when it is in phase n (n equals one to eight) when the block is operating normally.
S29 to S36 - FAULT1 to FAULT8
Block addresses of the phase n fault phases. These specifications identify the block containing the number of the phase the system should execute after phase n (n equals one to eight) when the block receives a bad input from the device monitor block.
S37 to S44 - REC1 to REC8
Block addresses of the phase n recipe values. These specifications identify the block containing the recipe value used to implement phase n (n equals one to eight).
N (Jump step number)
Identifies the step that executes after the current step completes.
N+1 (Jump step trigger)
A zero to one transition of this output initiates a jump step in the sequence generator block. The sequence generator block then executes the step identified by the jump step number. A zero to one transition of this value occurs when the multi-sequence monitor block proceeds to the next phase in the sequence (when the conditions defined by the step type are met).
N+2 (Jump step recipe value)
Recipe value defined for the phase that is to follow the current phase. If the block is held and a step is inserted, this value reflects the insert recipe value <S11>.
N+3 (Current phase number)
Phase number of the phase being executed. There are eight phases numbered one to eight. Although the step number in each phase can vary from sequence to sequence, the phases always execute in ascending numerical order.
N+4 (Insert step done)
Zero when an inserted step is being executed. It will make a zero to one transition when the inserted step is finished. This triggers the block to resume execution with the phase selected in <S9>.
0 = a step has been inserted in the sequence and is currently running
1 = the sequence is proceeding normally with no inserted steps at this point
0 to 1 transition = the inserted step has been executed and the block is resuming normal operation
NOTE: An inserted step sequence is complete (done) when the insert step trigger goes to zero and the step trigger makes a zero to one transition.
N+5 (Run/hold state)
Shows when the multi-sequence monitor block is in the hold mode.
1 = hold
0 = run
Figure 134-1 shows a multi-sequence monitor block used to control a number of sequences through real recipe table blocks and a remote manual set constant block. The operator uses the remote manual set constant block to select the values that will be output from the real recipe table blocks. For example, if the operator selects zero, then the first parameter value defined in each real recipe table block will be output from the blocks. The real recipe table blocks are the normal steps for phases one through eight in the multi-sequence monitor block (S21 through S28). By ganging recipe table and multisequence monitor blocks, any number of sequences with any number of steps can be executed. The operator controls which sequence is executed with the remote manual set constant block. To select different sequences, enter different numbers.