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SC100/200 Series Function Block Application Manual EM-6460-C
6.3 STEP SEQUENCE
6.3.1 GENERAL DESCRIPTIONS
In addition to relay (ladder) sequence type programming, the ‘step sequence’ type programming similar to sequential function
chart is available.
It is especially effective in describing a batch control process that needs exact conditioning to go to a next step in a batch.
The following five (5) types of commands are available:
OUTPUT ON : Once turned on, the output remains on until a next OFF command is received.
OUTPUT OFF : Once turned off, the output remains off until a next ON command is received.
BRANCH
: Activates a specified step in a specified block.
STEP
: Declares STEP number.
TIMER
: Step timer which runs only within a step without using an external timer device.
‘ON-delay’ timer or ‘step watch’ timer is selectable.
STANDING BY
Start PBS
Level L1
STEP A
• Pump P1 turned on
• Valve V1 open
• Agitator A1 turned on
• Valve V1 closed
• Valve V2 open
• Pump P1 turned off
• TIC-1 loop in Auto mode
STEP B
Temp T1
Temp T2
STEP 01
STEP 02
STEP 03
STEP S
Timer TM1
STEP ss
STEP C
Pressure P1
STEP 04
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EXAMPLE OF STEP SEQUENCE DESCRIPTION IN A BATCH PROCESS