The following is a structure diagram of the STEP2 block:
Behavior of the output OUT:
If the deviation (DEV = PV - SP) is less than the lower threshold dev_ll, the configured output OUT is set to 1. If however the deviation increases again, the output OUT is only set to zero if it exceeds dev_hl.
NOTE: To ensure that the block functions without errors, the output OUT should not be inverted.
The STEP2 function block has 2 operating modes available according to the value of the MAN_AUTO parameter :
Operating mode
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MAN_AUTO
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Meaning
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Automatic
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1
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The output OUT is calculated by the controller block itself.
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Halt
|
0
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The output OUT will be held at the last calculated value.
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